SO as you can see by the title, im haveing major issues. Ive been tuned by someone who claims they can tune, and am totally at a loss right now.

Mods: Hallman MBC, Walbro 255, Precision 880's, RNR manifold, Precision 35r, Tial 44m wastegate, Agency Power bov, 4in intake (reduced to 3in for MAF), ported and polished head (springs retainers), BC 272's

As far as wide open throttle the car feels fine. Dynoed at 456hp and 367 tq at 27 psi (93 octane). I feel like the tuner only tuned Wide Open Throttle, and did nothign in the lower RPMS for me.

Driveability issues are what upset me at this point. I do have my ROM if someone would be so kind to take a look at it for me.

 

You sure it's not surge, some 35's surge like a mother low rpm/high load.

 

The injector latency may need some adjustments. Can you log the STFT? If it fluctuates more than + or - 5%, that could be the problem.

 

latencys aren't going to have any effect at all in 5th gear. the pulse width is large enough that the .4ms is going to be minimal at best. if he is having studdering problems and cannot accelerate at all, it is a bigger problem then that. i would second GST. if you floor a 35r in 5th at 2k rpm it can surge like crazy. AFR's will drop to very rich and the car will buck.

 

lol ur avatar pic is the one someone used to make that arrogant poster....lol!!!

 

Yes KevinD ... thats pretty much exactly whats happening... i floor it in 5th.. and it just sounds and feels like my car is totally fallin apart..

5th gear is the worste... but it also happens in 3rd and 4th... i was hoping that it just the lower timing was off and needed to be adjusted a bit.

 

And how would i determine/combat surge?

 

Anti surge housing, different A/R etc.

What are the specs on your turbo?

I had a customer car that had a 2.3L and FP35R. It would spool that thing so fast it surged like a mother if I started at anything below 3,000 rpm.

He upgraded to a HTA35R with anti-surge cover and it all went away.

Here is what the surge looked like in the log:

 

Did this happen right after the supposed "tune?" If so, thats the problem. Take it to someone who KNOWS they can tune an evo. Don't risk blowing your ride up by someone who doesn't know how to tune one. Good luck.

 

its a Precision BB 3582r, has a ramhorn manifold, external 44m wastegate


and yes it happened right after the "tune" which is why i wanted someone to maybe look at my map..

and when he did tune it.. he only tuned wide open throttle because at the time i had a tial 50mm with the maf.. so car kept stalling.

 

So your large turbo and vent to atmosphere bov are causing drivability issues in high gears at low rpm's and you are blaming the tuner..... nice.... downshift.

 

pm sent.

 

^^^^ Mojo ... downshift and drive at 4.2k?? around town?? ya ok buddy... stfu if you dont have any reasonable input dick. stay outta my thread.

And if u read my last post... it clearly states... "AT THE TIME I HAD A 50MM...." which means... no longer do i have a tial 50 mm.... sorry for making you seem like a complete moron..

 

Wow, easy, no need for name calling, I'm sorry if I offened you, my input to your problem is the same as in the other posts above in that I think you might have a hardware problem and not a tuning problem.

I just thought you were very quick to blame it on a tune. From what you are saying its not that the car will not maintain speed in 5th gear but that the car will not full throttle accelerate in 5th gear without surging, right? I quote "Yes KevinD ... thats pretty much exactly whats happening... i floor it in 5th.." To expect a highly modified evo to have the same manners as a stock evo is just not reasonable.

As stated in the posts above it sounds like you are getting compressor surge which has nothing to do with fuel or timing maps but rather the turbo and the bov. 4K around town in fourth gear, what is the speed limit in your town? My hopefully helpful input here is that probably the cheapest solution to your problem is to not floor it in high gears at low rpm's which is bad for the car to begin with but rather to go easy on the gas or downshift since your other alternative is probably to start swapping out parts.

 

Ah, maybe I misinterpeted the thread. I thought WOT was fine but part throttle/cruise was bad. If that were the case, I thought that the tuner only adjusted the injector scaling but did nothing about the latency, thus causing driving issues at cruise.

But yes, if you are having issues at WOT in the lower RPM range, it's more than likely compressor surge.