Just got back from a 400 mile trip. Aluminum tape still looks new, it isn't burnt up and the red lettering on it is still there. I have had the smell of burning adhesive, but I also took the tape right to the edges of the wrap so it's probably where it actually touches the exhaust. I'll put it on jackstands in a couple of days and check closer and take pictures.

Next time I wrap it I'll use silica fiber based wrap and I'm working on an idea for layers of aluminum foil between wraps. May just get some now and try a short section as a test.

Next update will be a few days. Need to go to work/rest.

Got my ign-1a coils set up last night. Pardon the mess this is not final installation, it's just a prototype! This morning I wired in ion-sense and looked at the feed on an oscilloscope. I only wired into the L1 coil and there is noticeable noise from the other coils, but the peak for combustion is obvious. I'll spend the rest of the day refining till I can have some useable data, but just knowing it works is a relief!

Oh and the aluminum tape is still holding up.

Cleaned up the signal a bit, but after setting the scope to trigger on T1 it didn't look right. I think I'm just catching the ignition coil ringing. Need more time to figure out what's going on.

AP dwell table is confirmed ms*256.

nice to see progress----
Glad the wrap is holding up for you--if you dont track the car it may work well for you?

Changing circuit design. Delphi based system didn't give me the results I wanted. Parts on order, working on other aspects of the build until they get here. May be a little while until next update.

Edit: also those AEM coils are monsters. Pulled the trailing boot off to try and change the curve in the scope and the coil kept firing the spark plug until the boot was completely clear by >1/4" and then it proceeded to light me up like a Christmas tree.

Pics or it didn't happen

installing your own taser system?
Be careful man--!
reminds me of that Home Alone in New York electrical prank. lmao!

Sometimes you need to take a step back to figure out what you are doing wrong. I thought the IGN-1A coils were perfect, but they have some sort of internal spark gap. They show no continuity with the ohm meter, so they also carry no current to allow for ion sensing.

So instead of using the coil to charge a capacitor for ion sensing, I used an (ahem) external power supply. I only used it on the L1 spark plug, and because I don't have any 20kv diodes yet I can't attach the coil. So the trace is of a chamber with no leading plug firing, and the engine is running like crap, but it is a reading of chamber current!!! Should be able to clean up the signal with a couple filters and use it to detect knock. Also should be able to scope it and use it for tuning. Progressing quite nicely.

Here's the video, the trace isn't very visible but it's getting dark and I don't feel like redoing the video in the dark.

I hope everyone realizes how sweet this can be?

Harlan--is this a good link in trying to understand what you are doing?
http://www.google.com/url?sa=t&rct=j...d4c6wrVd3tTTLg

For those of us that have trouble putting it together?

That link is informative, but these are better:
http://www.google.com/url?sa=t&rct=j...,d.b2I&cad=rja

or this one and associated links:
ion sensing? anyone here have a clue?

compared to the results found by this one using conventional pressure detection:
In Chamber Pressure Testing - Page 2 - NoPistons -Mazda Rx7 & Rx8 Rotary Forum

At this point I'm just glad to have a recognizable curve. Cleaning it up and processing comes after I get the hardware set up better. Should detect inaudible knock easily.

Major update on the build should be coming soon. I bought some ev6 flex fuel injectors after being told by a very reliable source that they are nearly bulletproof for metering water and corrosive chemicals. Have the bungs, and will begin building the intake when I have time. Nice to know that I'm a little less out in left field that I thought I was.

Thanks for the links.
I found this one that includes a study on the effect of humidity ( water injection) on the ion formation and PPP. Its old research but still pertinent?
Really cool stuff.

http://www.google.com/url?sa=t&rct=j...AACr9L2BOlMzCw

That's the site that got me started on this. Saab's study was groundbreaking.

Got some more testing done, still don't have the trace as clean as I want. A mystery signal keeps coming and going. Gonna rethink everything and try to get a better signal. Good news is that it does work on a rotary, and it can probably be done with LS2 coils. Still waiting on the big surprise to get here so I can do a major update.

Will be swapping parts/build to my new 8 as soon as she's inspected and registered. 04Mt with 96k. May have to rebuild, haven't checked compression yet.

i might have missed this in the thread somewhere, but you can run water thru the fuel injectors, it turns out volvo did it in the 80's

Group A Volvo Specs

its a little confusing, but they added another ecu and AFM/injectors just for the water, so they had a fuel ecu (CIS!), water ecu and ignition ecu.

like the website says they ran something like WM50 with some machine shop cutting oil... apparently that is enough to keep the rust away!

they also have traction control, which is neat in 1983!

Miniupdate: Compression on the blue 04 was bad. Rebuilt engine, reinstalled engine, car wouldn't idle/ run right. Only about 30min run time on engine. Checked apex seals free through the leading spark plug hole, and one apex seal is missing from the front rotor.... Time for the re-rebuild. I sure hope that apex didn't do horrible damage to the sides/housing, but only one way to know for sure.

Yes Volvo and others have used fuel injectors for water injectors. Also flex fuel injectors will run straight (distilled) water with no ill effects.

Trying to get enough energy to pull the engine I just put in.

So your rebuilt engine failed?

Just rechecked the apex I thought was gone, guess it was a combination of the angle and the light, but the seal is still there. Guess that's what happens when you storm off and drink a beer instead of checking for sure. Now all I need to do is deflood the engine.

BTW the stock battery terminal connectors suck. They should be part of the first $100 thread, because they are just that bad.

yes you are right about that---good boat battary connectors are top notch.

walked off? LOL--I have cussed out every tree in my back yard several times each--and I have a lot of trees... perseverance old friend:)

Good news/bad news. Think I've figured it all out, my side seals were just too tight. Tried to go as close as I could to 2thou on the seals. Set up a jig with my drill press and an old rotor. The problem is that .002 is very hard to read accurately with our side seals and the arc you cut for the corner seal, so what I ended up doing was grind the seal until it would barely pop in and out easily when evenly compressed in the slot. I knew then that the break in would be a little sketchy because of the close tolerances, but now I'm paying the price.

The engine starts (albeit hard) and runs for about 3-5 minutes then shuts down almost like a loss of fuel. I was pulling my hair out until one right before it shut down time it started running on what sounded like one rotor face (very uneven but repetitive). After cooling off it starts and runs again. I think what's happening is my side seals are still binding a little with the corner seals and eventually they get stuck in the compressed position and the engine shuts down on low compression. The good news is that it's getting slightly better with every run. At first I had to pull start the thing and it wouldn't run below 2500 rpm, now it will start and almost idle normal until it warms up. A slow and steady break in and this engine should be drivable, or something will break and I'll be tearing it apart, either way the problem will resolve itself.

Let this be a cautionary tale about grinding your own seals! Go a little beyond pops in and out easily!

BTW Denny, I think your inbox is full.

Well, guesswork is over. Front stationary bearing is gone, took the e-shaft with it. Everything else is fine, seals were actually starting to free up and make good compression. :wallbash:

At this point, I'm not sure why the failure occurred. Maybe I nicked it when installing the e-shaft, maybe I missed something that contaminated it. One thing is for sure, I messed up.

Now to redo everything right.

Ouch. You live and learn.

that's a pretty rare failure ..................

yes it is.....need to check oil supply and balancing?
Is this the ceramic coated engine?

Time to fess up. Yeah, these were the bearings I coated. Looks like the tolerances closed up too much causing oil starvation. Can't specifically blame the dry film lubricant, it works as advertised, but the directions have you burnish with scotch brite to remove any excess then let any remaining run in. This didn't work well enough for me, now I'm using some emery cloth and getting a better finish/fit. Funny thing is that the dry film lubricant saved the other bearings.

Also worth noting, fitting side seals is different on the Rx8. Because they are wedged and not rectangular they fit differently when fully compressed than they do when they are just inserted in the slot. So when you are test fitting them, be sure to fully compress them to ensure proper clearance.

Getting this engine back together and maybe back into the car when I have time off next week.

Been gone for a while involved with other things, now I'm trying to finish this build.


I have the experimental engine back in the car, it has near zero clearance side seals and break in is proving difficult. Starts and idles fine, but when it gets hot the side seals start binding and it loses compression. It might wear in the seals, it might not.

A call to rotary resurrection may be in my future. I have more cash then time right now and I just want this done.

The rear mount turbo idea has been trashed. It was becoming a really ugly baby and I've learned enough from the effort to make a front mount turbo meet my goals.

So I now have an agency power exhaust, and the piping from a PTP turbo kit. Still planning on no inter-cooler.

Out of everything I've done the knock safety system and the water injection control have worked great. So I'm focusing my efforts on what I can make work.

Oh and fiberglass exhaust wrap covered in foil tape does hold up well. Had it on for over a year and still looked ok when I took it off.

You should have went Isuzu V-6 bro.

/\ nah man .... Saab turbo all the way !

So it was impossible :uhh:

Hope to see it finished soon, nice to see people still venture outside the box!

Removed the cursed engine today and used the time to check manifold/omp clearance. It's a tight fit but should be ok. I think this engine is becoming a lamp, maybe a clock. I tried too much with too little experience and it was a total failure, but I did learn a lot from it, some of which I'm willing to share.

Ceramic coatings work fine on rotors, and can be applied at home as long as you follow the directions.

Don't screw with bearing coatings at home, leave it to the professionals.

You can uncap yellows at home the tip dimensions change slightly and heat shrink is required to keep the rubber grommets from falling off.

Exhaust wrap covered with foil HVAC tape stands up well to heat and makes a great thermal barrier. I originally used fiberglass, but am changing to lava rock because I did see some degradation.

Here are some pictures of the old and new wrap. The new stuff isn't covered with foil tape yet, I wanted to check clearance first.

Yay another PTP! If you have any questions I'm happy to share my experience. I can tell you you'll def want some shielding between the up pipe in that last pic and the OMP lines/pump. My forward line blistered and melted pretty quick. Ultimately I replaced all the lines with braided SS. I do like how you flipped the OMP connector so it's pointing up, didn't know you could do that. I shielded the whole thing and haven't had any problems, but may give that a try just as an added measure.

Here you go.

Rx-8 OMP Shield

Thanks but no thanks.

Went through your build thread slash, looks great!

Right now I'm working 70 hours a week on nights at work, so I'm getting done what little I can. I have my knock detection/failsafe box hooked up for baseline data. So far it can detect knock, stop the ignition, and detect rpm. The problem is that it's creating some signal noise which causes misfires at high RPM. I think the ecu is miscounting teeth on the trigger wheel at high RPM. Looking for a solution either in code or in wiring. Once this is resolved and my new engine gets back I'm ready to boost/tune.

Thanks Harlan! 70 hours a week is harsh when you have a project like this waiting at home :)

I am interested in your knock box. I am battling with timing getting pulled myself. I haven't figured out if it is actual knock or the sound of my open wastegate dump triggering it... Doesn't matter how much fuel I add the timing is always pulled the same.

Low rpm or high rpm ?
If it's low , I had the same thing and gave up with the idea that it might be knock ,so I disabled the knock sensor .

If it's above 7k then it's not the knock sensor. Above 7k the combustion chamber is too big and the burn time too short to prevent knock, so the ecu ignores it. Also high rpm knock is less dangerous because the short duration prevents hot spot formation, so it doesn't start to snowball cycle to cycle. This is also why coolant and oil temp begins to spike at higher rpms. I may have a trick to boost power and get rid of knock at high rpm, but I'm not willing to share until I know I'm not crazy.

The knock box is my biggest push right now. With it the rest of the build falls into place. I'm still planning on releasing the source/schematics for it. I may sell a kit for it as well, and offer support with the kit. It's too early to think that far ahead, the thing barely works and still has some issues.

Oh and I now have a S2 transmission on it's way to me. So when the engine gets here and the transmission gets here, and I get some time off work, things should get exciting.

New parts are fun! Would love to see your knock box schematic when you are ready.


How low are you talking? My timing starts getting pulled around 5K-5.5K RPM all the way to 7K where the max knock retard RPM is set and them it jumps right back up.

I've also been waiting for some details or something to buy.

Just thinking a little. After 7K the ECU ignores the sensor because the chamber is too big and duration is short. Does that mean that the knock can't move across the chamber fast enough to be a problem? or does that just mean the detection system is too slow to correct it in time?

no .... mine was 3000 through to 5000 ...... nothing above 5000

Neither. Knock breaks down the boundary layer and allows more heat to transfer to (and stay on the surface of) the rotor and housing. At low RPM this can cause either preignition or just faster burning of the mixture. Either way it's like adding timing in an uncontrolled manner. This makes the knock worse, and the cycle snowballs until the knock is bad enough to start breaking things on its own or the preignition has raised housing temperatures and pressure and that breaks things.

At high rpm there is less time for this heat transfer to take place even with a little knock so it's mostly harmless. With a stock tune this is true, with a turbo, well lets just say it's questionable.


This is also why we lose so much power at high rpm in the form of heat to the coolant and oil. Just cruise at 6k and you'll see your coolant temp start to rise rapidly. Minor knock is happening and that is causing more heat to transfer to the housings.

I think I have a solution that will decrease knock at high rpm, but I need my knock box working first because it's... a little out there.With the right split you should be able to push more timing for both NA and turbo, and get better power too. We'll see.

I'll post my current source to the knock box thread, as well as the schematics for it. It's pretty darn simple right now, but it may have to get more complex if I can't resolve the phantom signal.

Nothing is possible when your basic premise is flawed ...

If you tune a rotary anywhere knock like a piston engine you are doomed to fail...listening for knock in a turbo charged rotary is like trying to use birth control weeks after sex....not going to have a good outcome

Hate to break it to you, but the stock ECU already hears knock and adjusts the tuning accordingly. It works just fine and engines don't get damaged until you push beyond what the ECU can control. If you disconnect the stock knock sensor (and dummy it out or leave it hanging) then monitor for knock you will find some inaudible knock, and some low level audible. Just driving around normal during the winter with premium gas and a stock tune I sometimes hear knock. Every time you start up the engine knocks, it sounds like a little belt squeak, but it's really knock. And it's natural because the ecu is just blindly putting in timing and fuel until the engine catches.

What we need to prevent is the bad knock. The stuff that causes engine damage quickly. That stuff snowballs fast, but if you catch it early and cut the engine life is fine.

A lot of what the stock knock sensor hears isnt knock....and if you log knock retard you will see that. The S2's changed the knock setup from the S1 strategy for a reason. You need to tune for safe timing and then slowly move up slightly as you can. You cant tune with too much timing and then hope the knock sensor will save your engine. It wont...and you will have another rebuild that you didnt need to do....possibly with a lot of broken parts to replace.
The Renesis is different than prior Rotaries....but dont throw out the basics. ..they still apply :)

I don't know what's right or wrong but I have logs with timing pulled, up to 5*, and other logs with nothing pulled, same loads, same fuel, etc. I've beat my head against the wall. I'm not the brightest but it seems the sensor is doing something but I get nothing in the logs as far as sensor knock retard, just the timing itself. Would love some insight.

The stock knock sensor is looking for a set amplitude per RPM. It does not care about frequency and can get fooled by any number of noises, but that doesn't mean it's worthless. If it is pulling timing on some logs and not on others I would start searching for anything that could be causing knock. Sure it could be spurious, but why take that chance?

As for knock retard and logs, it's been previously discussed, the AP does not log actual knock retard, it logs one variable and tells you almost nothing about what is going on.

https://www.rx8club.com/series-i-eng...-200224/page3/

If you put a 100k ohm resistor and a 10k pf capacitor in series and connect to the knock sensor signal (the yellow and red wire) you can then record what the knock sensor is hearing (or make yourself a simple pair of det cans) and then see knock clearly on a spectrograph. Or you can even filter light knock until the sound is obvious. If you want, send me a recording and I can show you what's knock and what isn't.

dannobre, I agree that you should always slowly advance timing to maintain safety, what I'm saying is that it's easy to completely override the stock knock sensor by advancing timing and never realize that the safety net is gone. I'm not making something that will replace stock knock control, I just want to make a safety net which can stop the engine before things go out of control and require a rebuild.

Thanks Harlan. Fazda pointed me to that thread as well. I need to spend some time reading.

S2 Transmission arrived today. Still waiting on engine. Knock box is still in a semi working state, gonna need to ditch the LCD display in order to get it completely functional, but no huge modifications to code. Think I should be able to have a knock based water injection system too, but no promises.

Back on the road. The S2 transmission feels a little clunkier than the S1. I haven't had a single grind, but the motion does not feel as smooth. Probably just need to get used to it.


Still getting knock control to a workable state, I may have a cheap off the shelf option waiting on parts. One way or another I will have a working knock based fail-safe before going into boost.

Engine breaking is progressing slowly. Just driving to work and back. I set up the throttle duty cycle to limit rpm to 5500-6000, but I don't know if it's working as intended because I haven't had rpm up that high! I think I'll set up the throttle duty cycles when I'm done to be both an RPM limit and allow for flat foot shifting/ launch control. Need to find out under what circumstances the ECU uses each table before I can do that.

My OMP wiring modifications are working fine, no CEL/limp mode, so the ECU is reading the sensor. I think the OMP sensor is some kind of rotary encoder and not a potentiometer as I first though.

Oil filter kit is working like a champ with no leaks with stock oil pressure. I did have to give up on the higher oil pressure mod because it blew out filter o-rings when I had the last engine in the car. Here are some pictures of that, I'll take more the next time I have my bumper off wish I had documented it better in the first place.

Also have more maf/IAT info I'll be sharing once I have time to confirm.

Also, a shout out to Rotary Resurrection for building me a great engine!

Good to see you back at it!