Today while I was driving in freeway at 70mph in 6th gear, I down shifted to 4th gear with revolution match as usual to exit freeway. Right after I did the heel-toe, I heard 2 loud "pop" from 1st under the car & then the back exhaust. Then I stepped on the gas to see the engine response and found out the engine would rev but felt like there was no boost/power, and then 2-3 seconds after that the engine died with all warning lights up and could not start again. It cranks but could not start. The car was at 6-7 psi on boost, boost controller was not connected and the Innovate wide band showed 10.8-11.2 all the time when on boost. Did I blow my engine? Any opinions are greatly appreciated.

Thanks and regards,

Sammy

Boostspike?

Did you blow a hose or connector on the IC or exaust piping on the turbo???

A big leak = no start???

i had a boost spike, got a pop, pop, pop and then blueish black smoke, car went into limp mode turned it off, drove home fine and the rest is history under the for those who blew an engine thread, mine cranks but does not idle good,

think we may be in the same boat kinda!

The car was at 6-7 psi on boost, boost controller was not connected and the Innovate wide band showed 10.8-11.2 all the time when on boost.

Are you sure the boost controller was off? All values 0's?
Also, on the boost controller solenoid... is the 3rd port open? Did you remove the clear plastic cap from that port, should have no lines connected to it.

who did the install?????

beers

Are you sure the boost controller was off? All values 0's?
Also, on the boost controller solenoid... is the 3rd port open? Did you remove the clear plastic cap from that port, should have no lines connected to it.

The boost controller is not connected to the solenoid yet, only the boost guage function is connected.

My friend's shop did the install. They have plenty of experiences dealing with turbo cars like the Evo, the STI, turbo 350Z, etc, but this is the 1st turbo RX8 for them.

Tonight, we tried to start the engine but no luck. The engine cranked, but in a much slower speed compared to usual (maybe the battery was no good), we smell gas, heard the compression, but the engine just did not fire up. They suspected the engine/spark plugs might be flooded. The lights on the interceptor was normal, no red light up. Tomorrow, they are going to pull the spark plugs (the RX7 plugs recommended from Mazsports) and see what happen, may be put the original plugs back to see if it can fire up.

Still have no idea of what happened and why it happened today in the freeway!!!

Boost Controller not connected :O You were asking for trouble with that .. If you are lucky it might just be as simple as hose or line loose. May be even a flooded engine. If you are unlucky, it might be time for you to bite the bullet.

Boost Controller not connected :O You were asking for trouble with that ..

I don't get it. I just connect the vacuum hose to the back of the boost controller display to read the boost level, the solenoid of the boost controller is not connected to any host. So what kind of trouble was I asking for?

Have you done compression tests on both rotors yet?

Did you make sure the vacuum hose on the interceptor is not pinched. Scott heavily warned about that. Check that out, and also take the front passenger wheel off, and verify all your connections are tight. I could be wrong, but even if you did blow one of the rotors, you should still be able to start her up. Unless you blew both?

If you blew an apex seal you wouldn't have good compression when cranking, so I would expect it would sound funny. Really check for any burst hose couplings, that could definitely cause those symptoms. Also pull a plug, apply a ground to the outer metal on the plug, and check for spark while your cranking. Or buy one of those spark testers from an auto store.

well if you are smelling gas the first thing to do it take alll the plugs out, give the battery a good charge or jump, disconnect the eccentric shaft sensor (on front of engine near plugs and pulleys on driver's side green connector i think), crank the engine three or four times for about 4 to 5 seconds each time to get rid of the extra gas and oil, clean the plugs, re gapp them and put them back in, connect the sensor back and she should crank up with either the pedal to the floor or no pressure on the pedal, will smoke like crzy but it should cranked unless there is other damage.

Not sure why you would have flooded it though cause of a boost spike, may be damaged and it just happened to flood because it did not crank

i am very interested in seeing how yours runs, like i said, we may have similar problems

I've read in the TSB to disconnect the eccentric shaft position sensor, but what is the point of that. Why does it need to be disconnected?

i had a boost spike, got a pop, pop, pop and then blueish black smoke, car went into limp mode turned it off, drove home fine and the rest is history under the for those who blew an engine (http:///#) thread, mine cranks but does not idle good,

think we may be in the same boat (http:///#) kinda!Not history,yet. I haven't seen any resolution for your reading a 17 afr.

Pulled the plugs, they were all flooded. Disconnected the fuel injector fuse, with gas pedal floored and cranked several times to get gid of fuel & oil inside the engine. Then put back the stock plugs and cranked again, the engine started, but could not hold idle. Pulled the rear rotor plugs again, they are all wet. CEL code misfire, system too rich. It looks like the rear rotor does not fire. Still don't know what to do!! Check all vacuum hoses and they are fine.

Do you have spark in the rear rotor?

yes it does have spark

Compression?.......
Vac check?

Injector stuck open? ( kinda unlikely:D: )`

I've read in the TSB to disconnect the eccentric shaft position sensor, but what is the point of that. Why does it need to be disconnected?
one of the several ways to kill the fuel so it does not flood more. I don't think ecu realizes its actually turning unless the sensor is connected, not sure about that though.

i did a poor man's compression check on mine, took the leading plug on one rotor out, unhooked the ecentric shaft sensor, turned the engine over by cranking and listened for three strong puffs. If not three then there is real problems.

You and I both probably should take ours for a real compression check, i think i will be doing that tomorrow just to rule out that problem for once and all.

how did your idle? at what rpm? how long did it hold?

i did a poor man's compression check on mine, took the leading plug on one rotor out, unhooked the ecentric shaft sensor, turned the engine over by cranking and listened for three strong puffs. If not three then there is real problems.

You and I both probably should take ours for a real compression check, i think i will be doing that tomorrow just to rule out that problem for once and all.

how did your idle? at what rpm? how long did it hold?
you will need to perform a compression test, the compression reading should be around 110 psig to 130 psig. in both rotors. compressiong differences between rotors are 20 psig.

When you say there is a spark, I'm not sure if you have actually pulled the plug and visually verified a spark or not, but sounds like faulty ignition coil(s). The same thing happened to myne a little while ago and I had those exact symptoms including the car starting on stock ecu but not on Interceptor. You can visually see if they're melted, there's pics posted on this forum of what to look for, just do a search. It will look like a melted spot right around the electrical harness. Of course if you have visually verified spark on at least the leading coil for the rear rotor, then never mind all of the above.

when we pulled out the 4 plugs and used the a remote switch to crank the engine (no fuel injection), we could feel the front rotor got more airflow from the spark plug holes compare to the airflow to the rear spark plug holes. i guess there are compression problem in the rear rotor, did not have a chance to check the compression yet. the engine starts right after disconnecting the interceptor and use the stock ecu. it idles stable with stock ecu but looks like the rear rotor is still not firing (cel code stated misfire on cyclinder 2, idle rmp lower than expected).

maybe you broke a apex seal in rear rotor do not start until perform compress check, Why because you can breake the rotor housing too.

just did a compression test, the front got 90 psi, and the rear got almost zero! i think i need a new motor!

should i rebuild the motor, buy a reman, or buy a brand new motor?

we checked all hoses, no leak, how did i blow the motor?! can someone please advise some possible reasons? i don't want to blow it again once it gets fixed.

wow you blow the apex seal that,s mean that you should need to replace the entire engine. because i 'm my blow first engine when we openen it we found a rotor damage, housing,ect..... when we goin down to mazda to buy the parts there are tooo expensive we opted to buy a used one .

boost spike, too much compressed air, not enough fuel. You need to make sure your boost controller will stop the boost at the psi that your map is tuned for.

what did you use for your compression test? a conventional piston compression tester or a special rotary one? just wondering.

It is the same tool for rotary and piston is reading scale is in PSIG. if reads less than 80 no way.

not really, the piston type has a check valve, the rotary type does not and gives three pulses for all three compressions per rotor. the piston type only does on compression and the check valve makes the needle stay at that number so unless you remove the check valve, you could get a faulty reading, say a good reading on one compression but not know that you have a bad reading on the other compressions.

not really, the piston type has a check valve, the rotary type does not and gives three pulses for all three compressions per rotor. the piston type only does on compression and the check valve makes the needle stay at that number so unless you remove the check valve, you could get a faulty reading, say a good reading on one compression but not know that you have a bad reading on the other compressions.

the check valve is only to keep the hightes reading , we have in our shops both the only diffrences are tha mazda are electronics and it control the cranking by using internal timer but it have too an internal check valve to archive the highter value so how it keep the measure when remove it.

Pull the valve from the end...it's like one found in the valve stem of a tire ...Schreader Valve

You will then get three pulses per rotor....kinda fast but you get truer readings.

Good enough to see if your motor is F**Ked

is it in the end of the hose or the gauge itself?

It depends. It's usually where the button to release the pressure is....

Mute point!!!! If he has 0 pressure then not even one pulse is there. The only reason for the special gauge is that you can see if one seal is bad. So if you can't even show one of them is working why bother?

^^ True....with 0 compression it doesn't matter....but I was only answering questions :)

With readings like that you might as well call Paul at Mazmart and see about getting a new engine......

Aftermarket turbo kits and ecu's don't come with an engine replacement warranty should something happen.

I don't even think of any warranty issue as Mazda voided the whole warranty 6 months ago after my 1st transmission was broken. But I am still questioning the reason causing the blown motor. I had the boost reading at 7psi at max, a/f ratio at 11.2 at max when on boost, egt 1300 F at max, no boost controller connected, no vacuum leak, etc, the engine was flooded, and I was using interceptor with map tuned for California 91 octane. So what casue the blown motor? Maybe my motor already got some internal damage/pre-mature wear even before the turbo? Now I am ready to order a reman engine, but my concern is how to avoid the same incident after the new engine. One thing I realized on the map of interceptor was the super rich a/f in cranking and idle. Mazsport got the map from a CA forum member who dyno turned the car 2-3 weeks ago. I have the map checked by a local rotory tunner after the install but did not have a chance to fine tune it before blew the engine. Another observation was that yesterday, the engine crank/idle much much easier and better with the stock ecu alone!

I don't even think of any warranty issue as Mazda voided the whole warranty 6 months ago after my 1st transmission was broken. But I am still questioning the reason causing the blown motor. I had the boost reading at 7psi at max, a/f ratio at 11.2 at max when on boost, egt 1300 F at max, no boost controller connected, no vacuum leak, etc, the engine was flooded, and I was using interceptor with map tuned for California 91 octane. So what casue the blown motor? Maybe my motor already got some internal damage/pre-mature wear even before the turbo? Now I am ready to order a reman engine, but my concern is how to avoid the same incident after the new engine. One thing I realized on the map of interceptor was the super rich a/f in cranking and idle. Mazsport got the map from a CA forum member who dyno turned the car 2-3 weeks ago. I have the map checked by a local rotory tunner after the install but did not have a chance to fine tune it before blew the engine. Another observation was that yesterday, the engine crank/idle much much easier and better with the stock ecu alone!

I can't tell from this, did you alter the original Mazsport interceptor maps for your car? Did someone try to tune your car?

youre runs lean is supposed not more than 1200 d. f. with complete exhaust, and 91 oct gas maybe youre run the engine in detonation, this can cause a apex seals broken.

Have you done compression tests on both rotors yet?


There is a quick and easy way. I did this with my RX-7, should work the same.

Remove the 2 plugs from one of the rotors. With the fuel cut off, crank the car. You should hear 3 distinct, and strong "whoosh"es. Try this for both rotors. If you hear one stron whoosh and two "farts", it's a bad apex seal. If you hear one soft fart, it could be a bad side seal.

May not be state of the art, but it works.

Don't remove both plugs from each rotor. Only remove the trailing plugs. Make sure there is no fuel going to the engine by removing the fuse that disables this. Not sure which one it is on the RX-8. You'll know real quick if one rotor is different from the other.

Don't worry about what you're a/f ratio was. It on it's own is unimportant when it comes to detonation. Too many people rely on a/f ratio to tell them the whole story and it doesn't. Timing in relation to a/f ratio is what is important but you must know both. There could have been other reasons that caused this. There could have been a boost spike, there could have been intermitent spark, there could have been a sticking fuel injector, etc. Some of those aren't very plausible but it could happen. One possiblity is that the plugs got fouled from rich a/f but kept running. They could have had carbon build up on them which led to them staying "hot" igniting the incoming mixture early and causing ping much like a diesel engine glow plug lights them off. Again not saying this happened but using it more to illustrate the point that there are many things to consider other than just thinking it is necessarily an ecu issue. It may very well be but who knows?

If this happened to a piston engine, you could just rebuild it stronger. Too bad you can't do the same with the Renesis, at least not yet. Someone needs to develop some stronger seals.

Sorry to hear about your blown engine. This really s*cks. Fortunately, alot of the top subject matter experts are here to help. Hopefully you can diagnose what went wrong, which will help some of the rest of us.

If this happened to a piston engine, you could just rebuild it stronger. Too bad you can't do the same with the Renesis, at least not yet. Someone needs to develop some stronger seals.

we don't need stronger seals, the stock seals are plenty strong up to 500whp. We heard this from every rotary expert at sevenstock, the issue isn't seals, its proper tuning.... period.

People don't take the time to tune the engine properly.

It takes more than just time to tune the engine. Unfortunately it also takes more than "just" experience. When Scott programmed the Interceptor he did so with what he considered a conservative map that should work fine with 91 octane. Unfortunately CA 91 octane is not the same as other state's 91 octane--it's much worse. Consequently all Interceptors in CA need to pull something like 5 degrees of timing from Scott's original map just to prevent detonation. (I'm probably the guy who provided Scott with the CA dyno info.)

If you didn't have a BOV then I can easily see a boost spike.
________
Side effects from depakote (http://www.classactionsettlements.org/lawsuit/depakote/)

Another observation was that yesterday, the engine crank/idle much much easier and better with the stock ecu alone!

Yes, the stock ecu will crank and idle much better than with the interceptor connected. The interceptor runs a bit richer at idle and there's other issues of cold starts being worse with the interceptor.
I believe it has to do with how the stock ecu controls the spark plugs at idle .... it's different from how the interceptor controls them.

If you didn't have a BOV then I can easily see a boost spike.

You mean 'wastegate'?

that sucks man, when I blow a headgasket I can change it out in 3-4 hours with about a $100 in gaskets. Makes me nervous to mod my rx8 when I see these apex seals go that require a new engine.

^^^
No worries. Just get someone to tune your engine that has a lot of experience and is from a reputable shop.

does anyone know how much a new engine cost?

does anyone know how much a new engine cost?
I know how much a used one is from me with low miles . PM me if that is of any interest to you.
Sorry for hi-jacking the thread.
Paul. :)

Sorry to hear you've popped your Renesis. I know how you feel.

You can get a new engine for less than $5k.

The advantage of rebuilding your engine is it will be less expensive to port it since it will already be torn apart. While you're at it, you might want to consider the Racing Beat oil pump mod too.

:grouphug:

It takes more than just time to tune the engine. Unfortunately it also takes more than "just" experience. When Scott programmed the Interceptor he did so with what he considered a conservative map that should work fine with 91 octane. Unfortunately CA 91 octane is not the same as other state's 91 octane--it's much worse. Consequently all Interceptors in CA need to pull something like 5 degrees of timing from Scott's original map just to prevent detonation. (I'm probably the guy who provided Scott with the CA dyno info.)

If you didn't have a BOV then I can easily see a boost spike.

I have the BOV.

does anyone know how much a new engine cost?


~$2600-$2800 plus $1000 core exchange for a reman.

Yes, the stock ecu will crank and idle much better than with the interceptor connected. The interceptor runs a bit richer at idle and there's other issues of cold starts being worse with the interceptor.
I believe it has to do with how the stock ecu controls the spark plugs at idle .... it's different from how the interceptor controls them.
The stock ecu fires the plugs in negative split at idle which means the trailings fire first. At high vacuum/low load levels this allows you to run a leaner mixture than with conventional firing order. That is, in theory.

Now the reman is coming tomorrow. I am debating between the tubo & NA. I like the increased power & torque with the turbo, but don't like the slow throttle response, and mostly the fear of another blown engine.

By returning back to NA, eventhough it has less power & torque, it has the quick throttle response, plus no worry when flooring all the way until redline (I did that 80% of the time during the 1st, 2nd & 3rd gears before turbo).

Should I give it a try on the turbo one more time? If yes, which parts in the install/set up show I pay special attention to, should I use the factory spark plugs or the RX7 plugs recommended by Scott (Mazsport), and how should I break in the reman engine with the turbo but withour final tuning?

Any opinion is highly appreciated. Thanks in advance.

Sammy

Well, if you had slow throttle response and couldn't floor it, you had problems with your tuning.
If your general solution with tuning problems is to accept said problems, then N/A is probably a better choice for you.

Well, if you had slow throttle response and couldn't floor it, you had problems with your tuning.
If your general solution with tuning problems is to accept said problems, then N/A is probably a better choice for you.

I could floor it all the way to redline without feeling any power loss, but just the throttle response was not as quick as NA.

I will not accept any problems regarding tuning, I was planning to get it tuned after the Christmas, but it died on Christmas. I am in Los Angeles area, any tuner recommended?

I'm really sorry to hear about your car... that's a damn shame :(

I had my pressure plate give out about 2 weeks ago, that was a horror for me... can't imagine what a blown engine would do.

Good luck with your new parts!

It is likely your engine blew from improper tuning for California octane. You're A/F were probably okay, but most others in Ca needed to retard their timing by a few degrees to avoid ping due to poor gas quality. When you reinstall your turbo, after a break in period of easy driving - no boost, have your car tuned by a reputable rotary shop and you shouldn't have any problem. Worst case if your engine goes again you can always sell the turbo and Interceptor to pay for your third engine. That really sucks though!

It is likely your engine blew from improper tuning for California octane. You're A/F were probably okay, but most others in Ca needed to retard their timing by a few degrees to avoid ping due to poor gas quality. When you reinstall your turbo, after a break in period of easy driving - no boost, have your car tuned by a reputable rotary shop and you shouldn't have any problem. Worst case if your engine goes again you can always sell the turbo and Interceptor to pay for your third engine. That really sucks though!


I was already using the map tuned for CA 91 octane gas. I think I was using PUR NRG's map.

Should I use the RX7 plugs as recommended by Mazsport? Or keep the stock plugs for turbo set up?

Now I recall the fact that when I was in full throttle from 1st gear until 9K and then shift to 2nd gear, right after shifting to the 2nd gear the car had hesitation / unstable acceleration for about 1 second and then accelerated smoothly all the way to redline again. But it happened only 2-3 times so I didn't think of any potential problem about that. Any inputs?

The rx7 plugs are 1 heat range colder so they will help prevent detonation. You could also go 1 heat range colder on stock type plugs, but they foul more easily than the rx7 plugs which can be an issue when using the colder plug. I am using the Mazsport plugs and haven't had a problem with them.

Even if you were using a map tuned for 91 octane, each car is different as has been proven time and time again on here. There is no universal map. You really need to get your map tuned to your car.

When I took the car to my tuner, he asked me about the idle map on the interceptor.

On the idle map under 0 Hg, the reading is 0.05, which is almost zero. He asked if there is any specific reason for that setting? As he said that the map should be relatively gradual in readings for RX7 with microtech.

Any inputs?

http://www.rx8club.com/attachment.php?attachmentid=65025

I was already using the map tuned for CA 91 octane gas. I think I was using PUR NRG's map.

Should I use the RX7 plugs as recommended by Mazsport? Or keep the stock plugs for turbo set up?

Now I recall the fact that when I was in full throttle from 1st gear until 9K and then shift to 2nd gear, right after shifting to the 2nd gear the car had hesitation / unstable acceleration for about 1 second and then accelerated smoothly all the way to redline again. But it happened only 2-3 times so I didn't think of any potential problem about that. Any inputs?
Double check to see if that was PURNRG's map or mine. I had to retard my timing even more than his, because I running and able to maintain higher boost levels. And like Ryan was saying each car is different, so you'll have to tune no matter what. It could also be the case, that the gas in So.Cal is different from NorCal. You guys have just a tad more polution, so I wouldn't think that was out of the question. Also, both PURNRG and myself have RP supercat, and RB exhaust, is that your set up also?

Double check to see if that was PURNRG's map or mine. I had to retard my timing even more than his, because I running and able to maintain higher boost levels. And like Ryan was saying each car is different, so you'll have to tune no matter what. It could also be the case, that the gas in So.Cal is different from NorCal. You guys have just a tad more polution, so I wouldn't think that was out of the question. Also, both PURNRG and myself have RP supercat, and RB exhaust, is that your set up also?


I have B&B test pipe and HKS exhaust.
I actually wants to have the car tuned by more than 1 good turner.
My current tuner is an expert on Microtech but he works on RX7 only in the past. This is the 1st RX8 for him and he does road tunes.
I would like to find another reputable rotary tuner in South Cal with a dyno just to make sure it is tuned right.
Any recommendation on reputable rotary tuner in South Cal?

I wouldn't even waste your time going to multiple tuners, that's just a waste of time and money because all that will matter is who makes the final adjustments. Find a reputable tuner who has experience tuning rotary motors and has access to a dyno. You really need a dyno to do it right.

My nephew installed a Greddy on his RX8 and it also died after 2 days. He said it was using a lot of fuel during this time. I pulled the plugs and replaced them with the updated ones (156$ at Mazda) but it still wont start. There is also a severe battery drain on it. Now it is at a tuner to check it out - I hope it isnt blown.

Gunnar

A map is only good from one car to another if both cars have the exact same setup. If the car te map was setup for had a stock exhaust but the other car had a midpipe and catback, the same map won't work and would probably blow up the car with the exhaust mods. Not saying this is what happened here just showing how these things work. The car with the exhaust mods would need more fuel and/or less timing to not have any problems.

On a map based system, you absolutely can not run the same map with different mods. You will blow things up. This was the issue with the 3rd gen RX-7's. All the time I see people asking for a map that would work with their boost level even though they have a variety of different setups. Then people send them one. It doesn't work that way. If you want to run a certain map, you MUST use the exact same setup as the car that the program was made for. This will be fine. If you have ANY differences from the base car, you risk detonation. Depending on what was done it may be bad or it may not. The map based standalone systems must be tuned according to each mod on the car. This is isn't something someone can guess at, make a map on the guess, and then send you to use. It won't work properly if you have any differences from that car. If the aftermarket ecu's ran off of mass air flow or air flow meter based systems, there wouldn't be near this issue. There is nothing wrong with map based systems and nothing wrong with Mazsports tuning. It works great on the car the map was intended for. The consumer must make sure that they have the same setup. If not, a little less agressive timing combined with a little more fuel can compensate but it will never be perfect as this s a guess on the safe side. It was a lack of understanding of these ecu systems that lead many to believe the rotary in the RX-7 is unreliable. Don't let that be the case with the RX-8. The problem is never the engine. It is always the tuning in relation to the mods on it. If your system differs from the car that the tuning was made for, you MUST do something to fix it.

A map is only good from one car to another if both cars have the exact same setup.If this were even true for the RX-8, it would be wonderful. However, even with "identical" setups, no two RX-8s are compatible.
Why? Who knows. Sensor variation, build variation, gremlins? I don't know.
Probably the same reason some Renesis motors have blown mysteriously while others have happily churned on through hours of seemingly endless detonation with no problems.

Plenty of people have installed the Greddy kit on otherwise stock drivetrains with the stock Greddy tune and had different results.

A map is only good from one car to another if both cars have the exact same setup. If the car te map was setup for had a stock exhaust but the other car had a midpipe and catback, the same map won't work and would probably blow up the car with the exhaust mods. Not saying this is what happened here just showing how these things work. The car with the exhaust mods would need more fuel and/or less timing to not have any problems.

On a map based system, you absolutely can not run the same map with different mods. You will blow things up. This was the issue with the 3rd gen RX-7's. All the time I see people asking for a map that would work with their boost level even though they have a variety of different setups. Then people send them one. It doesn't work that way. If you want to run a certain map, you MUST use the exact same setup as the car that the program was made for. This will be fine. If you have ANY differences from the base car, you risk detonation. Depending on what was done it may be bad or it may not. The map based standalone systems must be tuned according to each mod on the car. This is isn't something someone can guess at, make a map on the guess, and then send you to use. It won't work properly if you have any differences from that car. If the aftermarket ecu's ran off of mass air flow or air flow meter based systems, there wouldn't be near this issue. There is nothing wrong with map based systems and nothing wrong with Mazsports tuning. It works great on the car the map was intended for. The consumer must make sure that they have the same setup. If not, a little less agressive timing combined with a little more fuel can compensate but it will never be perfect as this s a guess on the safe side. It was a lack of understanding of these ecu systems that lead many to believe the rotary in the RX-7 is unreliable. Don't let that be the case with the RX-8. The problem is never the engine. It is always the tuning in relation to the mods on it. If your system differs from the car that the tuning was made for, you MUST do something to fix it.


Thanks rotarygod for your input. I will definitely get the car tuned for my current setup.

Regarding the tuning, does it matter if the tuner has experience on particular ecu such as the microtech in particular car such as the RX8, or it doesn't matter as all tunings are based on the same concept/theory?

I could not find a reputable tuner who is specialised in RX8-microtech setup. All I could find are tuners specialised in Power FC for Evo, RX7 or microtech for RX7.

Thanks again for all inputs.

Thanks rotarygod for your input. I will definitely get the car tuned for my current setup.

Regarding the tuning, does it matter if the tuner has experience on particular ecu such as the microtech in particular car such as the RX8, or it doesn't matter as all tunings are based on the same concept/theory?

I could not find a reputable tuner who is specialised in RX8-microtech setup. All I could find are tuners specialised in Power FC for Evo, RX7 or microtech for RX7.

Thanks again for all inputs.

I would choose the shop that has experience with the RX7 and microtech.

^ I second the statement on variability. There is no way to build a single map that's good for even most 8's. I debated this point before the Interceptor was delivered but some people (ahem) claimed that having the control that the interceptor gives would make it so we can all run the same map. Now that the Interceptor has been installed on a few 8's we know this is far from true. Yes, running a map tuned for certain mods when you don't have those same mods is stupid. But, its been proven with the eManage, and now the Interceptor - there is no way to generate a set of engine management parameters that will work on everyone's car, even with the same nominal hardware. That's why the stock ecu adapts in the first place. If you install a turbo kit and expect it to be plug and play, you are a fool and you should expect to: (A) have $hitty performance because the engine runs too rich, or, (B) blow your engine because its too lean.

With regards to the issue of gas: I would argue that if the difference in gas is really causing problems, then the map sucks to start with. Anything tuned that close to the edge is playing with fire. That would be like tuning with a water injection system and running it so close to the edge that it detonates without the H20. When you run out of water you blow your seals. I doubt its really the difference in fuel, but if it is, you guys should tune a little more conservatively. You might get some bad gas one day yourselves...

Sammy, the tuner that tuned my car, and PURNRG's car had no previous microtech experience. He was able to figure it out with the help of Scott, and mentioned it was one of the easiest to tune software that he has personally dealt with. I'd of course recommend someone who already knows the software, but if not, make sure he speaks with Scott before and while you are tuning.

The reason why you can not use the sam boost maps for different setups is due to efficiency of the turbo system. If you have a sturbo on car A that has a stock exhaust and a turbo system on car B that has a fre flowing exhaust, the differences in exhaust backpressure will effect turbo efficiency. It would be possible for car B to run less boost but make more power. The turbo wouldn't be working as hard to overcome the backpressure which would mean it isn't making the intake air charge heat the car with the stock exhaust is. A map based tune doesn't know of these efficiency differences. It goes beyond just a simple intake temperature sensor. It just knows that at a certain boost level it is to send a certain amount of fuel to the engine with a certain amount of ignition timing. If we added a larger turbo that could flow the same air in cfm but at a lower boost level, it would obviously be sending more air to the engine if it were at the same pressure level. More air needs more fuel. It is a little confusing.

The Renesis engine is actually very consistent engine to engine. What is not consistent is the ecu. A standalone system like the Interceptor should also have consistent results with tuning on different cars provided each other car has the same basic setup. If another car doesn't, there may be issues. If a piggyback style of ecu is used, the inconsistent factory ecu is not being taken out of the equation and can continue to mess things up. This is why I wouldn't touch a piggyback with a ten foot pole on this car.

The RX-8 is nothing special and neither is the engine. Sorry to break the news. The Renesis and the RX-8 are not rocket science. It is not the engine or the car that is inconsistent. It is the factory ecu. The Formula Mazda cars all use the same factory built engine that is off of the exact same assembly line as the RX-8 engines. Nothing different about them at all. They all use the same Motec tune and they all make very consistent numbers. This alone proves there is no issue with the engine as far as consistency is concerned. The fact they have a Motec does nothing to affect the consistency anymore than a Haltech, Microtech, etc would.

As far as tuning goes, it may be a good idea to take the car to be tuned by someone with a Microtech only because they know how the Microtech software works. A Haltech, Microtech, Motec, Megasquirt, Wolf, etc all work the exact same way in what they do and how they do it. The software is the biggest difference as is the number of load points. The theory and understanding is all the same. Someone who can tune one of them properly should be able to tune any of the others properly as well.

Nobody is saying that you can run the same maps for different setups. We are saying you can't run the same map for the same setup. I believe if you read the Mazsport forum, you'll see this for yourself.

the differences in exhaust backpressure will effect turbo efficiency. ... The turbo wouldn't be working as hard to overcome the backpressure which would mean it isn't making the intake air charge heat the car with the stock exhaust is.



huh? Can you explain this?

There is no external power applied to the turbo. It can't 'work harder' or easier to make boost. The turbine only spins at what ever rate its design gives for a given set of exhaust gas flow parameters. It can't 'work harder' to overcome slow exhaust gasses - it just won't spin as fast and won't make the boost or will have a lot of lag. The compressor efficiency is what it is for the pressure ratio and intake flow rate. The work done making boost, or making heat, is the same regardless. Its only dependent on compressor design. The compressor side doesn't know or care whats going on on the turbine side.

You can absolutely run the same map for the exact same setups on different vehicles. How do you think every car gets tuned from the factory? The RX-8 is absolutely not any more special or dificult than any other car in this regards. It is only the stock ecu itself which is an issue. It's not an engine problem.


The exhaust side of the turbo has everything to do with what is going on with the intake side. Pressure is not always a constant with flow. There is more to it than this. As a generalization (not set in stone), for every 1 psi of exhaust backpressure you have, you need 2 psi of intake pressure to overcome it. Decrease your exhaust backpressure by 1 psi, you can run less boost to make the same power level. If you ran equal boost with less exhaust backpressure, you would have to retune the ecu as you would be making more power. It is not pumping air at the same efficiency and this means that you can not run the same fuel or timing. There is alot of information on this topic all over the internet.

You can absolutely run the same map for the exact same setups on different vehicles. How do you think every car gets tuned from the factory?

With a program that adapts to the variability of the cars. You can run the same maps. There's nothing to stop you. But you get vastly different results. This is true even for totally stock 8's and has been shown many times over.

Decrease your exhaust backpressure by 1 psi, you can run less boost to make the same power level.

Now that I agree with. Your other post talks about the turbo working harder to overcome the back pressure. It didn't sound to me like you were talking about running less boost, it seems like you were talking about back pressure changing the compressor efficiency.... something in the statement "the differences in exhaust backpressure will effect turbo efficiency" made me think that....

If a turbo were setup to make equal power on 2 different cars but one had a better flowing exhaust, the turbo would be working harder on the car with the more restrictive exhaust just to make the same power. It would need more boost, which is more heat, and a faster spool rate. Compressor speed may be related to boost pressure but it is not related to power output. Boost pressure is never directly related to power output on it's own. It is also not directly related to engine stress. If we have a more restrictive exhaust, boost pressure in the intake manifold may stay the same but power will go down as the turbo isn't compensating for the power loss. You need to work the turbo harder by spinning it faster to get the same power level.

quick and easy.

if the exhaust flows better. the exhaust turbine spins faster at a given rpm.. also with that the intake compressor spins faster. thus more flow at the same rpm...

more flow same map would go toward lean...

beers

With a program that adapts to the variability of the cars.
There is no variability to the cars. They are very consistent. What makes them seem like there is, is really only a variability with the factory ecu itself. That's what causes all the issues. No program adapts to a variability between cars. That would be impossible to tune and would be like expecting an ecu to automatically compensate for either a V8 or a V6 engines differences compared to each other if we were to install the same ecu between either one. Isn't going to hapen.

quick and easy.

if the exhaust flows better. the exhaust turbine spins faster at a given rpm.. also with that the intake compressor spins faster. thus more flow at the same rpm...



That would only be true if there was no wastegate.

That would only be true if there was no wastegate.

sorry,

before the waste gate opens.... does not the waste gate open at a set psi...not flow volume????

i am trying to get this back from years gone past...

beers

going to make a cocktail now

There is no variability to the cars. They are very consistent. What makes them seem like there is, is really only a variability with the factory ecu itself. That's what causes all the issues.

Oh I see. That explains all the different results that people have with the same hardware, even when removing the factory ecu from the equation using the Interceptor.


No program adapts to a variability between cars.

Really? I guess I would point out that the fuel trims are one very obvious way that the ecu changes the management parameters from the baseline configuration and adapts to that particular vehicle's characteristics.


You state that the engine is quite consistent, but its not just the engine that we are dealing with. Its a complete system. While one component might have a fairly tight distribution, the assembly of engine, sensors, flow characteristics, etc. doen't necessarily. Its just statistics. Each car is going to be different. Those differences have been documented over and over on this forum.

Fred -

Try moving a PCM from one stock RX-8 to another.

Allowing that they all have the same flash, why do the problems follow the engine, not the PCM?
I like what you are trying to do, but you are basically wrong.
The PCM is IDENTICAL from one RX-8 to the next (provided they are on the same EEPROM). What changes are the tolerance on the sensors, actuators, injectors and coils and a whole slew of variables on the motor itself that mostly stem from dynamic seal clearances.

It may be possible that there is a large deviation between the temperature sensors and mass air flow sensor used between cars that will cause these readings but the Renesis engine itself is incredibly consistent. They all make about the same power regardless of who's car it is in. It is not an engine issue.

An ecu like the RX-8's doesn't adapt to different engines. If it did it would adpat to being installed on a 4 cylinder. It can't. It try's to look at it's readings that it receives and maintain a certain value according to what it is tuned to do. That is not adapting to a different engine. That is making your tune work properly according to what you see. This goes back to the above statement. If there is a low tolerance for consistency between sensors, this will affect what the ecu sees and it could be interpreted as a deviation between engines when it isn't an engine issue at all. These engines are extremely consistent. There are no issues with them. If there are still issues, check the sensors or the ecu's. If the ecu's check out consistent, check something else. Don't blame the engine though. That will never fix anything as it isn't the problem.

It makes sense that the variability is in the engine and the sensor readings that the ECU gets from that engine. It does not make any sense that the ECU's are different. Programming is programming. With the same flash...the programs are the same..........

I would think that the ECU gives different sensors varying amounts of importance...and thus variability in specific sensors would have larger effect than others on the output of the ECU....

What sensors seem to be most important ?? MAT IAT Baro ECT TPS?? I would expect few variables in the Eccentric shaft sensor...it will either work or not....

Mazda sourced the MAFs from more than one vendor, so that might explain the HP differences between cars. Even though they're built to the same Mazda-supplied spec, variations in manufacturing techniques, materials, etc. result in significant functional variance.

All of the MAFs are from Mitsubishi. They are the same MAF as on the Subaru WRX, BTW.
They do have some varying output, however.

functional varience of the maf has been talked about for almost 2 yrs now. It's there. Canzoomer tried dealing with it. Now whether or not this in itself causes the differances being spoke of here--probaly not. It has been shown that changing maf's between cars really doesnt change how the car runs.
Just our luck it has to be something very complex. There is something to be said about a distributor and a holley carb.
Olddragger

Yes. That is the point. The sensors have variations that may or may not affect the function of the motor. However, different motors perform differently regardless of their subset of sensors and PCM. This is because of some variation in the motor itself.

I preferred Carter carbs, but you haven't lived until you've rebuilt a Rochester.

Weber, no contest. :bash:

Webbers are easy to rebuild. Its synchonizing all 12 of them that was hard.

wOOt ! Two Thousand Posts!

I have 6X2 brls on my 275 and had 4X3 brls on my Boxer. Does that count as 12?
Or does it have to be 12 units? If so what the hell was that on?

I stated in an earlier reply that my nephew's car died 2 days after installing the Greddy turbo kit. He did not have it tuned. It was towed to the Mazda tuner afterwards where it was found to have been blown from an extremly lean mixture. He did have an aftermarket exhaust on the car. If anyone is reading this and is thinking about installing a turbo kit without having it tuned please think again. This is going to be about a $6000 dollar lesson.

Gunnar :nono:

$6k?!? Just how bad did he mess it up?

2.5k for a new motor and 3.5k for the install.

a fool and his money.

beers

I am not sure on the rotary engine what happened but the case is damaged. The replacement motor is new not remanufactured - over $4000 plus install and calibration of the computer. It also included installing boost and another gauge. The cost is actually quoted at $5600 but I have never had anything come in at cost. Several of his friends initally installed the turbo kit and he drove it 2 days (or actually a day and a half) without having it tuned. They will be getting the old engine back (40,000 Miles)

^ I second the statement on variability. There is no way to build a single map that's good for even most 8's.


umm, yes there is; it's called "flash tuning" the factory PCM :dunno:

^^ We see how great that worked out for Mazda over the last 6 flashes and the variability from one car to another.http://www.mazdamaniac.com/portal/smiles/badrazz.gif:wallbash:

At least it will be more predictable...

umm, yes there is; it's called "flash tuning" the factory PCM :dunno:


ummm, not the same thing at all. The factory PCM adjusts fuel delivery via fuel trims. The maps we are talking about do not.

only because everyone isn't on the same flash tune :dunno:

only because everyone isn't on the same flash tune :dunno:When "K" was out, people had all different kinds of behaviors on completely stock cars.
"R" was even worse.
"M" was as close to uniform as we've seen and it still has a lot of variation from car to car even though the ones and zeros are all the same.

only because everyone isn't on the same flash tune :dunno:


What the heck are you talking about? You seem to be saying that the maps that the emanage and interceptor use don't adapt to car-to-car variation because they aren't on the same stock flash.... I seriously hope that is not what you are saying.

i thought the interceptor-x was intercepting and replacing the signal rather than manipulating it (like the greddy emanage). if this is the case... why does it matter which flash you are on?

Because the factory PCM will still try to "correct" the A/F ratios any way it can until it gives up and throws a CEL which results in all kinds of nastyness.

It may throw a CEL with the Interceptor but that's all it can do. The factory ecu can't change anything else that would result in any nastyness.

The Interceptor controlls the DBW throttle also? How 'S-DAIS?
DBW gets limited to 80% and S-DAIS get shut down.

well maybe I misunderstood, I don't claim to be an authority, my comments are intended more toward inquisitive debate than to be taken as fact, hence the :dunno:

My car went in limp mode a while ago, due to a blow EGI fuse, and the RPM's were limited to 3k. So the factory ecu still has control over something related to the engine. Probably DBW. I think the Interceptor does control Sdias though.

The Interceptor controlls the DBW throttle also? How 'S-DAIS?
DBW gets limited to 80% and S-DAIS get shut down.
Mazsport has never had any issues with this. Ask them. I've never had any issues with the Megasquirt with a CEL causing other issues. You just have a CEL. That's it.

i thought the interceptor-x was intercepting and replacing the signal rather than manipulating it (like the greddy emanage). if this is the case... why does it matter which flash you are on?
You are exactly right. Any dealer flashes that affect the factory fuel/ignition maps will not affect the way your Interceptor-X equipped vehicle will run. Once it's tuned it's tuned, Scott