RX8Club.com

RX8Club.com (https://www.rx8club.com/)
-   Series I Major Horsepower Upgrades (https://www.rx8club.com/series-i-major-horsepower-upgrades-93/)
-   -   Definitive Greddy Turbo Fixes - Here they are (https://www.rx8club.com/series-i-major-horsepower-upgrades-93/definitive-greddy-turbo-fixes-here-they-81825/)

MadDog 02-05-2006 09:14 PM

1 Attachment(s)
So, I think I have the MAP pretty much where I want it now. AFR is around 11.7, lean spikes are pretty well mitigated.

Remarkably, I found that I can take an even shittier picture of my e-01 screen using my camera phone. But, I was pretty proud of how flat the AFR was. This run was made neck-and-neck with a 3rd gen RX-7. Neither one of us could gain any ground (private road). This was fourth gear to redline, followed by a short burst of 5th gear - I think...

The centerline of the graph is 7040RPM, 6.2psi, 11.7 AFR.

I just wanted to show people what I mean when I say you can get a really flat AFR curve using the eManage and this new fuel strategy. Nice, huh?

rkostolni 02-05-2006 09:39 PM

I'm very interested to see what kind of spikes I have with the Interceptor when those ports open. I'll definitely post a copy of my datalogs once I get my car back together. I'm not sure if you can adjust the resolution of the datalogs fine enough to see those spikes with my Mazsport unit though. I'll have to give Scott a call and see if it is a fixed rate or is somehow variable.

KJ238 02-05-2006 10:30 PM

Problem # 2 - Has anyone got any pictures of this 'fix' ? Since i dont really know what i am doing + mechanics dont really speak english, I need to see this to explain it to them...

I am also highly encouraged by this to give the ignition timing thing that i tried another go... Thanks MM, u da man...

09Factor 02-05-2006 11:07 PM


Originally Posted by MazdaManiac
One thing I found in my move to Phoenix is that the gas sucks!
Right now, I am running about 2° of timing retard for each pound of boost. I'll probably be able to bring some of that back once I narrow down to the spot where the rattles occur at WOT and full boost. Seems to be in the 4800 range, but I haven't had the time to tune it out.
In MD, this wasn't an issue and I only ran 1° per pound.
It will probably be a bigger issue when the temps start to creep above the 100°F mark.

yes Phx gas sucks and we pay good money for it too. Bastards !

Sometime when you show up at the pavilions i wnat to see your setup on the 8.

MazdaManiac 02-05-2006 11:27 PM


Originally Posted by 09Factor
yes Phx gas sucks and we pay good money for it too. Bastards !

Sometime when you show up at the pavilions i wnat to see your setup on the 8.

It is rediculous that 91 costs what 94 sells for in DC.
Add to that the corn and crap that is in it and it is almost as bad as Cali gas.
I just bought a 50 gal drum of Toluene. I'll have to hook up a way to pump it from the side yard to the garage.

I'll be doing that Apache Junction drive on the 19th. I probably won't hit the Pavillions until March because I'm usually in DC on the weekends.

MadDog 02-06-2006 11:08 AM

3 Attachment(s)
Here is the tuned MAP for both the 390cc and 490cc injectors. Its a pretty good tune with AFRs around 11.5-11.8. The lean spikes seem to be tuned down to 11.5 with not too much richness in the surrounding RPM. You can plainly see the additional fuel that compensates for the lean spikes (opening ports) in the fuel surface. I've looked at quite a few load points to test the tune against where the lean spikes occur in the RPM band. I'll continue to try to find any weaknesses in this MAP, but the most frequently visited cells are pretty good.

rotarygod 02-06-2006 11:20 AM


Originally Posted by MadDog
This run was made neck-and-neck with a 3rd gen RX-7. Neither one of us could gain any ground (private road). This was fourth gear to redline, followed by a short burst of 5th gear - I think...

The centerline of the graph is 7040RPM, 6.2psi, 11.7 AFR.

What's really impressive is the fact that even if you were racing a completely stock 3rd gen RX-7 (which is unlikely as they usually have "something" done to them), it is still running over 9 lbs of boost and weighs about 250 lbs less than you. Who says the Renesis isn't a good engine for forced induction?

MadDog 02-06-2006 11:37 AM

Yep. That 3rd gen was totally stock. I was still grinning from ear to ear!

I did just as good against a Ford 331c.i. stroker with headers - although he said it was running rich. Judging by the size of the backfire when he shifted, which was right next to my head, it was running rich. Still, he couldn't put any distance on me at all. From a roll, I was right on his rear quarter panel for at least a quarter mile.

MazdaManiac 02-06-2006 11:42 AM

Completely unacceptable!

Don't come back until you are hanging fender-to-fender with a C6 Corvette! :nono:

http://www.mazdamaniac.com/portal/smiles/smiley309.gif

MadDog 02-06-2006 11:51 AM

Alright, alright... I'll see if I can scare one up somewheres....

Actaully, its really cool! I met a couple of total strangers this weekend that recognized my car because they had heard the BOV around town! I guess the 8 is getting a little street cred' around here! :ylsuper:

MazdaManiac 02-06-2006 12:40 PM

It is still one of my favorite pastimes:

Stab the throttle as you pass through an intersection and watch the heads-on-swivels.

It is as if a wolf has lept into a pack of deer.

I was waiting for the light on Ray at 48th and a guy was walking hand-in-hand with his girlfriend through the cross walk. He was staring at the car the whole way through the intersection - so much so that his head was almost completely backwards by the time he got to the other side, at which point I stabbed the throttle and he walked directly into the post that holds the red-light camera.

MadDog 02-06-2006 12:55 PM

:yelrotflm :yelrotflm :yelrotflm

Haha! That's classic! I really had no appreciation for how loud the HKS BOV is until I was standing next to it while the car was on the dyno. That goddam thing is almost ear-piercing!

While I haven't made anyone look like a tool in front of their GF (except for guy in a 5.0 who thought he could take me. His GF was in the passenger seat at the time as I put about 2 lengths on him) I do like to cruise the strip where the local kids hangout to talk cars and hit the BOV as I go past a group of STi's or EVO's. No quicker way to get their heads to swing around!

MazdaManiac 02-06-2006 06:32 PM


Originally Posted by dannobre
Jeff: have you logged the fuel injector pulsewith to see which injectors the ECU uses to change the A/F when you change the timing?? Hope it's the P2's :)

The changes in A/F when you alter the timing is not a direct response from the PCM.
Advancing the timing produces leaner measured A/F and vice-versa.
However, this is not directly corresponding to correct mix for maximum power.
It is all interdependant.

However, the tidbit that is germane to all of this is that the secondaries are already operating close to the maximum that the OEM programming provides when you are operating in boost, so with the P2s severed the PCM has far less ability to fool with boosted A/F.
The secondaries actually have 15% or more left on the table even after the PCM consideres them done. The OEM tuning allowed for the P2s to do all the heavy lifting from that point on.
I can't help but speculate that Mazda intended for this motor to utlimately support closer to 300 HP than 238.


Originally Posted by two rotors
...the list price for fuel injectors from Mazda dealers(in Canada) is $198.65 each(part no N3H2-13-250). All 3 injector types,ie
N3H1-13-250A,N3H2-13-250 and N3H3-13-250A are the same price.
So if you divide by 1.13,that will give you the $US price,and you should be able to negotiate a discount.

I'm not sure where you derived those numbers, but the U.S. list price for injectors is $205.25 each. I verified this at three separate stealerships.
Ultimately, I got my buddy Jason at Gaithersburg Mazda to sell them to me at $144 each - $20 UNDER their cost (I made it up to him by buying a MS spoiler at the split price:)). I'll have a pair on Wednesday.

Too bad I won't get to install them until the 27th...:mad:

dannobre 02-06-2006 06:48 PM


Originally Posted by MazdaManiac
I can't help but speculate that Mazda intended for this motor to utlimately support closer to 300 HP than 238.

Looking at the way them implemented the injector staging that makes sense...why have the P2's come on like that....with so much extra room. That's not like a car co....:) they usually use barely enough to get the job done...hell....look at the coils they gave us.

"Death to all bean counters" at least the ones at Mazda/Ford :D:

two rotors 02-06-2006 08:03 PM

1 Attachment(s)
Well I am not sure what to tell you.I have attached most of the Quote!!!

MazdaManiac 02-06-2006 09:23 PM

1 Attachment(s)
Hmm.

MadDog 02-06-2006 09:47 PM

Its like those damn, dirty, dangerous Canadian drugs! Keep 'em out! KEEP 'EM OUT!! :mdrmed: :scratchhe

two rotors 02-06-2006 10:01 PM

You gotta love free enterprise,eh!! :patriot:

KJ238 02-07-2006 01:49 AM

OK... done the fix from problem #2... It really helped... Yes boost dropped but I have a boost controller... My ECU doesnt do funny stuff anymore like flood the engine at certain points... The car is more drivable now.... BTW I did it at the right hand turn just before the intercooler... It was too much of a hassle to get to the pipe right after the turbo...

I am gonna go home and cut the wires for fix #3 after i get off work.. Which map should i be utilizing. Can find mad dog's map which was mentioned in mm's first post....

If this works out, I'm gonna get that ignition harness to work....

MazdaManiac 02-07-2006 02:12 AM


Originally Posted by KJ238
Which map should i be utilizing. Can find mad dog's map which was mentioned in mm's first post....

Look at post #52 on page 4 of this thread.

MadDog 02-07-2006 06:38 AM

Alright... I'll cave.... I posted jpegs in hopes of avoiding having to type in the values for the latest 390cc MAP that I'll never use myself. But, in the interest of getting one out there that has the lean spike compensation, I'll do it. Give me a couple of hours and I'll post the actual .gsc file later this morning.

MadDog 02-07-2006 11:04 AM

1 Attachment(s)
Okay, here it is. This is my SeveredMap13, scaled for the folks with 390cc P2's. The fuel required exceeds the maximum duty cycle in some cells. Where this happens, I pushed the remaining fuel over to the Additional Injection map. I used my previous injector logs to estimate the S injector duty cycles at those RPM values. Then, with the PCM-specified duty cycle in hand, the value of the additional injection is (Sinj-100)/(PCM duty cycle). That should get you pretty close to the required fuel by making use of remaining capacity of the S injectors. The P1 injectors are already maxed out.

MazdaManiac 02-07-2006 11:13 AM

^^ You are a baaaad dude.

I'll have my new injectors in hand tomorrow. If I can get to Phoenix in only 3 days, I might have enough time to install them on Friday and have it ready for the Sunday drive out in Apache Junction.

MadDog 02-07-2006 11:31 AM

1 Attachment(s)

Originally Posted by MazdaManiac
^^ You are a baaaad dude.

I'll have my new injectors in hand tomorrow. If I can get to Phoenix in only 3 days, I might have enough time to install them on Friday and have it ready for the Sunday drive out in Apache Junction.


In that case, here is the 490cc injector map. I know you are running timing, but its probably easier to copy your old timing map over than to input all these values by hand. It litterally toook me about 2 hours to install the new injectors. The biggest pain was getting the upper intake manifold off.

MazdaManiac 02-07-2006 03:38 PM

Yah, I'll just cut-n-paste the timing MAP.

I'm not sure how long the drive there is going to take this time. Since I'm in a 22 foot truck pulling a trailer with our Miata on it, I don't think I'll be doing any of the trip at 130 MPH like the last time.
I get the truck Sunday in the AM and it will probably take me most of the day to pack it. Whether or not I start driving right away or wait until morning will depend on my motivation at that moment. I figure I am looking at 45 hours of road time, so the earliest I will arrive will be Tuesday morning. I'm thinking it will probably be closer to Wednesday night since I probably won't try to tackle it all at once like I did the last time.
So, I might get those injectors in by Thursday night and you will hear my hooting and hollering all the way in New Mexico somewhere around dawn on Friday...


All times are GMT -5. The time now is 02:27 PM.


© 2024 MH Sub I, LLC dba Internet Brands