might be a good discussion for another thread

 

You're right. The stock RPM limiter in the TCU is 6600...and you can run it up that high if you choose.

I don't believe there is any benefit to running the car up to 7000 RPM's....that is way too high.

 

His car runs and shakes and it def sounds like he bent valves.He might be lucky and it could just need a new valve set and the pistons are fine.

Either way Im just saying that valves get bent from them not being able to keep up.

On the usa spec e36 m3 it came with hydrolic lifters and could barely spin to 6800 and people were floating valves at 7300 rpms and the limit was set to 7200 rpms for MAX safety.the Euro version that has solid valves lifters can rev to 8k all day but needs a valve adjustment every year or so.If you revved that car another 100 rpms you would 100% of the time bend valves

I just dont think johncy melted his pistons and its related to the engine spinning to a higher rpm.We will find out once he opens it up.

Merry Christmas and please dont think I am trying to bring anything down from you guys.I just dont like when the forum atumatically points the finger to number 8 going when it could be an over rev issue.

 

I value your opinion and you provide much needed support here on the forum.

I don't think you are trying to hurt us in any way, but I do have to make everyone aware of the difference between TCU RPM limiters and ECU RPM limiters.

Going forward I will personally talk to each TCU tune owner and discuss their RPM limiter with them.

Merry Christmas to you, Angelo. I hope you're enjoying the holiday.

 

merry christmas to you ...

but the same way you don't like the forum pointing to #8 is the same way we don't like people blaming software. Expecially when there is so much documented proof of the #8 issues and fuel related data...

Time will tell...

 

Merry Christmas everyone! Thanks for the support guys! Vlad will be opening her up on monday. Skratch I hope its just bent valves or something. I have a video of my car right after the damage was done. I will post it after I open my gifts. LOL

 

I'm not saying this isn't a rpm problem but I have a set of heads getting redone now and the guy that is doing them said that with these low lift camshafts (.417/.418 lift) and the double springs we have stock it's not going to float the valves at 7000 rpm. These heads are built extremely well from the factory and that's why finding a good port job took exotic-55 a year because of the low lift cams we have to begin with. We're not dealing with huge lift cams that can cause the valve to get out of control with these cars if anything dosent like the high rpm in these engines it would be the pistons/bottom end. I'm wiling to be this was a fuel issue (lack of fuel). My car on stock injectors were maxed out so fast with only a 175 pulley and a few other things it was crazy. These engines were made to run rich and don't last at high rpm and lean

 

A 10.9 at the tailpipe means you're actually even richer than 10.9 in reality, just FWIW.

I wasn't referring to you making more or less power - simply that you could have a safer, more optimal AFR with some tuning tweaks. If Jerry says that 10.9 at the tailpipe is solid and you should leave well enough alone, then by all means go by that instead... this was JMHO.

LOL, no kidding. No one said it was. It's definitely not too lean - it's borderline too rich IMHO. At what AFR reading would you consider an E55 tune too rich?

 

Great post, and great service!

Merry Christmas everyone.

 

I meant too rich not lean. People get so caught up in what someone else thinks is too lean or too rich when all that matters is what the car likes and these cars like to run rich. My last forced induction car (04 cobra) ran perfect at 11.3-11.6 and is still running today and makes over 700hp

 

I'm not sure if it's related, but my E55 is having an issue with the car sticking in 3rd and 4th gears during WOT pulls where it runs into the rev limiter and won't upshift. I was racing a sportbike on the Richmond bridge the other night and we did a pull from 55mph to what must have been 150mph. It was basically a dead heat and the E55 was actually starting to pull on the bike before we ran into congestion. It's happened a few times lately and I'm always in S mode with the shifter in D when racing to let the car upshift. Sometimes, I'll be doing a WOT pull and then abruptly let off the throttle and brake hard to quickly slow down. The engine will stay in the high RPMs near the limiter and not upshift even after letting off the throttle and bumping the shifter to the right repeatedly. After 5 seconds or so, it will finally upshift and the RPMs will drop back down. This is very concerning to me.

I also had the EC ECU and TCU mods done and the rev limiters were increased. I'm not sure if this is related to those mods, but I don't remember the car having this problem when it was stock. I'd like to hear how others' cars behave when they do a WOT pull, are high in the RPMs and then let off the throttle abruptly. Does the ECU or TCU keep the revs up for a few seconds assuming the driver is in competitive mode and will accelerate again or is the car supposed to immediately upshift with RPMs dropping back down?

The car does feel faster with the ECU and TCU mods, but I want to figure out if I have a tuning issue or a transmission going bad. Car has 62K miles on it and no major modifications. Will try resetting the shift adaptations with the ignition/gas pedal trick when I get back home from the holidays to see if that makes any difference.

 

Yes, "rich" vs "lean" certainly is subjective, to a degree. I'd say mid 11's to mid 12's is pretty ideal, from what I've seen with the V6 and V8 Kompressor motors (so, 12.0 +/- a half-point). High 12's to 13's is probably pushing too lean, and low 11's to 10's might be a bit too rich.

You didn't answer my question though - out of curiosity, what would you consider too rich for an E55?

FWIW, by no means am I an expert - just relaying one man's opinion.

 

Any leaner than 11.8 AFR on a force induced motor is asking for it.

 

I wouldn't want my AFRmuch higher than 11.5 with these engines doing a long run. I would say anything under 10.7 at wot would be too rich. Another thing that is a problem is that the stock injectors might look ok on a dyno run but maybe your doing a long run up an incline when it's 25 degrees outside and that rich 10.7 on a dyno turns into a mid 11 AFR.like many have said the most important thing is to monitor the engines like there's no tomorrow. When I had Jeremy do a custom tune last year it was about 70 outside and I had a failing pump so after doing a trunk tank and doing a few runs below 30 degrees I leaned out .4 points.

 

Is that a fact?

Johncy, why not do a quick compression test to see what's up ( just to start with )?

 

What have you gained by going leaner?

 

The maximum power and torque made on my GTI 1.8T was at 12.0-12.2. At low 11's it would lose 5-8whp...which is not much granted but it never blew up at low 12's. I've tuned all my cars at high 11's, low 12's and the ONLY car I've even had blow up was my Infiniti G35 but it blew at a power level that most VQ's were blowing up regardless of A/F ratio so it kinda voids the argument per say.

Anyways, I'm not saying that everyone should run out and re-tune their cars to low 12's....but saying that it's "asking for it" to do so is also incorrect if it's tuned properly.

 

after reading this thread, i think most member forgot or miss post #103 from the owner himself. like someone stated ealier " you play,you pay". anything and everything will break onces it's push pass it's limit.

 

You will make more power at leaner AFR's (up to the point you break!) and you may make more power at 12-12.5 but you are taking a risk. I agree that high 11's is the safe level for forced induction motors. Anything in the low 11's or lower is way too rich and you can wash down cylinders. My other 2 tuned forced induction vehicles run high 11's at WOT.

 

Compression test will be done on monday.

 

I guess I am confused now with the TCU shift points verse the rev limiter. Lets just say for arguments sake you set your shift points at 6800rpms, and your rev limiter at 6600rpms, when going WOT you will just bounce off the limiter the whole time without the car shifting??

In essence, you need to set your rev limiter slightly higher than the TCU shift point??

 

Good luck. Let us know the results.

 

@chawakins if you are at full throttle it will slip the 200 rpms and make the shift. when i say slip its not exact on rpms the car cuts power but the engine can still over rev if your force it. now if you were talking about 400 to 500 rpms at full throttle it will bounce. At partial throttle it will work fine it will shift before red line. the only problem you will have is when you are in M.

 

You have a good attitude John. Really hope it's minor.

 

Watch this video

http://www.youtube.com/watch?feature...ow3QLJkY#t=98s