this afternoon while driving home i was screwing around a bit w/ the tst box. ez is always on setting 2 45 hp(i think) and tst was on 8/2. i never run torque to high just because of the stocker turbo. anyway i started getting in to it moderatley and as soon as boost spiked@ 40psi then started to settle to 35 or so, it started to sputter gently like it was running out of fuel or missing. fuel guage read 11-12 psi. anybody ever run in to this i continued to turn down the hp setting and try again. same thing but even less. then by # 6 hp setting this stuttering was almost undetectable. # 5 setting gone. weird or is this having to do w/ stock turbo being overfueled? any info would help folks

 

Your low pressure fuel supply is fine, but the CP3 can't keep up with the demand for fuel by the injectors. Time for a hot-rod CP3...

Not really.

Worry about egt's and a new turbo before worrying about the stutter. If you had a rail pressure gauge, I'd bet you'd see some real low readings.

 

thats kinda what i was thinking. if its choking for fuel w/ just the hp # up high, how is it going to act once sp66 turbo is here and i can crank up the torque #? just a weird sound. another thing w/ this stock turbo, almost feels like the clutch is slipping when i nail it on 4/2 or 3/3. lots of turbo noise but truck doesn't move much and rpm's don't come up until boost smacks 40 than comes down.....then it's go time. sound normal? turbo was electronically wastegated from factory. now has tst boost elbow from kit to manifold pressure to open wastegate conventionally. anybody? thanks for reading

 

Mine makes a ton of noise as it's building boost too, but my truck accelerates until full boost is made, and then it's slip city. Revs go to the moon but the truck doesn't go anywhere any faster. So much for the stocker.

I think you'd have better luck running 5x5 than 8x2. Your setting is giving you all the power at the top end. Why not bump the torque more? Your truck would feel a lot faster.

I don't think your FE is slipping. It's an on/off switch AFAIK.

 

no i don't think it is slipping either. i just found it weird for the truck to almost(wait)until the turbo did its thing than it's time to go. ive dialed up the tq # but im so **** worried that stocker turbo just can't handle th hit like that. am i wrong?

 

Napa, If you are building that much boost where is the power going if not slipping the clutch. You could be close to 400hp and 800 torque. Ask SB about this, they're here. I wouldn't go to 40psi tooo many times if I were you. Your turbo is better than mine and I don't like to get over 38 before it settles at 32 33. This stack is powerful and can drain the rail momentarily( less than 10k psi) but I doubt if that is your problem. When air and fuel aren't just perfect which I don't think they are when you are double boost fooling with a stack you can get some funny sputters. I get it on 7 anything but not on 5 anything and not on 6 5 or lower. I think that you and I have high boost but that volume of air is not dense (cool) enough to match the high fuel. The burn is getting overloaded with fuel and this burns late creates heat and boost but gives little power and torque as its happening past the power stroke (just saying those words makes me cringe). More dense air, water meth, bigger turbo, propane or any combination will cure those ills. ks

 

I have the same problem a fluttering sound, I'd call it

 

Your stock turbo will do fine with the tq dialed up, as long as you have the standard program. Mine is doing just fine, even after I've barked it a few times. (It was funny watching my girlfriend BARK the turbo on a 3-4 shift, she thought she broke something. I told her no, but she's lucky )

The standard program starts fueling at 10psi, and ramps up fueling until 24psi or so, when it's "all in."

The twins program will start fueling at 4psi, and it's "all in" by 12psi. That would certainly aid your turbo in an early death if you're not careful.

My turbo hasn't seen over about 35psi yet. First, my clutch doesn't hold any more, and second, I have my boost limiter set at 35psi.

The TST does feel a bit laggy until boost builds, but I believe that's due to the fueling curve. Plus, your motor needs that air to make power. I've gotten around that lag by running my BDDL in tow mode while stacked with the TST. It can be a bit smoky, but it runs great!