well we got to see one of the setups here @ the shop... owner came by for Vinny to take a look at the setup, didnt have any real boost in 1st gear as well.... heard this from another g35c around the area as well... so i think it def is a characteristic of the kit itself. If you guys see this setup in person, its amazing... you can see the amount of piping that it has to travel to to build up boost.

 

for some reason the gear dependent duty cycle isn't effective at all. I can turn say 3'rd gear all the way down to -50% and it will still hit the exact same boost level it was hitting at -1% I don't get this thing. It's so frustrating

 

Well I don't understand why if i turn the boost way up it will hit what i want it to in the first two gears but then the last three can't be adjusted down to compensate. why is that?

 

Daniel what did you tap on the ECU for the speed signal? I'd like to set gear dependent boost but, i'm limited without the speed signal.

 

DanielWebb

I have a lot of experience with 5AT and FI.

The spike between gears... get used to it. That is NEVER EVER gonna go away due the very nature of gear shifts... you are at WOT at redline right before the shift, the shift lowers the RPM in a matter of 0.2-0.4 seconds, and slows the incoming stream of air by 20-30% percent due to the drop in RPM/flow. It's impossible to lower the pressure by the boost controller since the phenomemon happens in the reverse direction, from the engine back to the turbos (upstream pressure wave)...and there is nothing a pre-turbo pressure regulator (i.e. boost controller) can do.

 

wow thats the best info I've gotten so far. So if 7.5-8psi is the max "safe" boost for this kit and the boost spikes to 9psi between shifts is that something i should worry about? I guess what i'm asking is do I need to set it lower so that the spikes max out at 7.5-8?

 

Don't know if you guys had the car sitting for more than 30mins coz if you did you need to drive the car a few blocks before the Turbo actually start producing real boost. This is one of the problem with Rear-Mount Turbo, it need it to be really warmed up before it can perform well. I see this as problem on the Track especially if you're waiting over 30mins just to get your turn (Hope Brake Boosting help). You tested the Auto STS car wait till you see mine... I'm lucky to hit 4lbs of boost on 1st gear and If I parked my car for more than 30mins I can shift from 1st-3rd hard and not hear my BOV open This happen after the meet and people are waiting for the sound and nothing


Julian mentioned the boost creep and that is why he put a Boost Cut off at 10lbs on my car (but I have 6mt). I did some logging and noticed that my peak PSI at 8lbs only last at 5K RPM after that it goes down to 7.5-6.5 all the way to redline. don't know if this is a work around he did to eliminate the boost spike (I have the UTEC BCS by the way)

 

interesting. I think I'm gonna try test pipes and heat wrap since no one else is gonna go for it.

 

Anyone on what do tap for the speed signal?

 

Yeah , smth like that...

Some EMS systems will have shift compensation wrt to timing... you are trying to lower power output in that .2-.4 seconds. So, take out 2-4 degrees of timing our or so...the shift is so fast, that you don't really run too high a risk for high EGTs due to timing retard. Additionally, have an enrichment for the shift as well if the EMS allows it. If you don't adjust AFR, it WILL lean out right at the peak of the spike, and enrich right after the peak, since some time passes between higher MAP detection and injector actuation, and it falls right on the tail end of the spike (on it's way down). The engine speed is decreasing while you are applying (effectively) 1.5 psi of higher boost, which represents a tremendous load, only your wheels are not connected and it all goes into the trans gears and the friction paltes. This is why I wholly support a good/aggressive valve body upgrade, so that that increased load doesn't wear the packs during WOT shifts.

So, leave the boost where it is, but do the shift timing retard (and/or enrichment). If you can't than do indeed lower boost a bit. EU, Fcon support it for sure, others may too, but I just can't speak to that directly.

 

anyone know if the utec supports this type of tuning? I'm assuming that if the emanage supports it the utec does as well

 

Do you think this would be helped by test pipes and/or heat wrap?

 

I'm having my exhaust track wrapped in two weeks or so. I'm sure I bought WAY more than I need, so if this ends up helping performance and you want the wrap I didn't use, it should be available.

 

make sure keep track of your boost before wrapping so you can find out if it actually help the car boost a little early.

 

word

 

I am now having the same issues as you guys with not being able to build full boost in first gear...i now have a lighter flywheel...13.5lbs....

 

Yeah, my Light FW made my spool worst. RPM does come a little fast on the Higher RPM but other than that I don't see any advantage. I think the Con out weight the Pro on having the Light FW with our setup. Man and this thing (FW) is freaking noisy below 2K. I'm swapping back to my old FW when I get a chance.

 

interesting I guess the light weight flywheel causes less load. Sub zero are you on test pipes or cats?

 

I thought you were 5AT.

 

Nah, I have 05 6mt(Revup G)