So final tune numbers were: 307whp and 388wtq, almost no knock, ~24psi, 27psi spike for a millisecond at 3200rpm. By 7000 rpm the car is running 20psi.

Is this 27psi spike okay, or are there going to be piston ring issues?

I will try to post the picture of the dyno.

Car runs like a bat out of hell!

Mods: GMS1 sensors, K&n drop in, ZZP catless downpipe

 

nice numbers man. Not to doubt you here, but the K04 will not hold 20psi to 7k. It would be great if it could, but it just aint gonna happen.

What dyno were you on just out of curiosity?

 

 

Sorry, my bad. It was 15 psi by 7000. Dynojet.

What about the boost spike?

 

in his defense, it's almost impossible to have absolutely zero knock WOT in these cars. There's always some small amount of false KR that registers in the midrange especially on warmers days with the GMS1..

 

I gotta agree with blue balt... close only counts in horse shoes and hand grenades... And since I don't want my motor turning into the latter I would think that knock under acceleration is definitely a no no. Thats what timing advance or retard and fuel ratio alterations, that your computer is supposed to correct, is for. The knock is what will shred your rings. Though the boost is a contributing factor to the knock because of added air causing a leaner mixture. I would talk to your tuner to make sure everything is right.

 

a brief boost spike to 27psi is pretty normal for a car tuned to 24-25psi. I wouldn't worry too much about it.

15psi by 7k sounds much more accurate..

 

Raver.. do you know how much KR your car was seeing and where in the RPM range it happened?

 

It's a known fact that these cars act weird for a bit right after a flash but he has no way of monitoring KR. Run it for a few days and go back to get it checked out to be safe. I'm willing to put money that your car will be ok and the KR will disappear

 

27 spike is not good..I don't care what anyone says. As far as 24...if you want to roll the dice? I say say UNDER 23 period. Why take chances? See my boost poll thread.

 

how much kr was it seeing ninja, around 2?

 

Your car is now a ticking time bomb...

 

I have the 24psi tune and I never see anything above 23.7

I have 0 knock in the mid range too so...

all cars are diff. I have seen knock when I first got my tune 1-2 but thats it, now I see nothing

 

Ok. There is zero knock on this tune all the way through. I am only worried about a boost spike to 27 psi from 3200 to 3400 rpm. At 7000rpm redline there is 2kr. And that is it.

 

I like all these people saying OH NOES ITS A TICKING TIME BOMB. My cars at 40k all of it tuned except for the 1000 miles of it breaking in. I spike at 27 and hold 24.5, I get wot on it 10-15 times daily and it runs fantastic. Just keep an eye on your o2 sensors and check your plugs. Regular maintence is all you need to do. I also run meth

 

I hold 20psi to redline no problem.. You do to, remember we looked at your log and I showed you how you held almost 21psi? lol

 

What are the IATs at 20PSI and 7K RPM?

 

Depends on teh ambient but usually around 100* give or take 5*

 

My car flows pretty well and since I have such a high baro pressure up here 6k ft elevation my **** is at about 16 -17 PSI by about 5500 to 6500...

It still pushes lots of power better flow = faster turbo car , the reason it is holding is probably because of back pressure . even the infini boost tunes it really isn't pushing that much boost efficiently.


Sucks my turbo runs out of juice so soon ..

I think a turbo that can hold 24 lbs up to 7k without too much overkill or spool time is the perfect match for this car . K04 just can't hack it up top . this is where I loose races to modded Fbods etc about 115 120 the car is like DO Not pass go Do not collect a win.

 

Thats why you gotta race on a track... The last F body camaro I drove handled like the USS Nimitz compared to this little go kart of a cobalt we all have here.

Generally speaking, the mid range/ upper mid range is what gets it done on a twisty track anyways.

 

You hold at 24.5....And it's been that way for almost 40K??
HMMMM...hard to believe that. You're on the ragged edge for sure..your call.

 

If it is a good tune and he is running meth which allows for more boost I dont see why not.

 

I dont care what you believe BYT has been tuning my car since it was almost brand new, im not on the ragged edge of anything. My motor holds fantastic compression and I perform regular maintence. It really is that simple, you treat the car right it will treat you right. Im sure nick can comment if he feels it is necessary. People having problems at any boost levels are generally people who should have found a better tuner or who just had straight unlucky defects. The only issues ive had are my 424ftlbs ripping my transmission up like a fat kid trying to get at some twinkies, and that was mostly driver error at the track anyway

 

It does not help you that your baro pressure is 80 kpa (11.6psi) compared to 101 kPa (14.7 psi) at sea level. 3 psi less inlet pressure into the compressor means less pressure (and flow) out.

 

ok....so back to my question about a 27psi spike for 200 rpm between 3200-3400

Should I be concerned?

While it is a 24psi tune, from 4300 it starts tapering off 23, 22, etc....