mdelgado

Hey guys, new here and I was hoping you'd be able to help me out. I have an 02 Tahoe with 80k on here, it's the flex fuel model with the 5.3L and I installed a procharger SC about 8 months ago. The tune was done by Black Bear performance. Intake is just the k&n FIPK and exhaust is a single flowmaster series 40 with dual out. I did install the FMU even though my pump should be able to keep up alright.
So I need new tires and wanted to burn my old ones up. I've done a million break stands in cars before but I can't break a tire loose and I'm pretty sure it's not me. No i don't have it in 4wd or 4auto.
I don't get crazy performance out of the SC either, its a little faster than stock but nothing to write home about. Any ideas how I can troubleshoot? Do I really need to go bigger injectors and smaller pulley to get any significant performance out of this thing? I don't want to go nuts, it is my daily driver and I do tow a lot, but I'd like to at least be able to chirp the tires.
Let me know what you think

Mangled03gmc

iTrader: (95)

What boost level are you running, when you had the tune done, did you ask him to remove TQ management?? Also what size wheels and tires are you running.. Is the converter stock or aftermarket( higher then stock stall) ??

mdelgado

Hey John, I'm not sure of the boost level, it's the stock pulley that came with the kit, 5 PSI I believe. I never ended up installing a boost gauge. I wasn't sure where to install the sensor since whatever boost the pump makes gets immediatley sucked into the engine, so it wouldn't be accurate?

BlackBear did confirm he removed the TQ mgmt.

The converter and tranny are stock, except for a shift kit and corvette servos I installed for 2nd gear.

Mangled03gmc

iTrader: (95)

5 psi is not a whole lot esp with stock gearing and converter.. What size tires are on the truck? And food for thought prochargers like gears, big converters, they are basically a belt driven turbo, live better with rpm's.. Is this a issue that has just come up or has it been like this since you added the blower?? I would add a boost gauge. There is a place rite on the intake mani, that can be used for a boost.vacuum port..

mdelgado

Thanks for the quick responses!

I'm running 285's on 20's

I hear ya on the rpm's, the truck is very responsive when cruising between 30 and 50mph and you kick it down and get on her.

What spot on the mani would give me the most accurate reading? Can I just T off one of he vacuum lines to the FMU or that bypass valve on the intake?

How small of a pulley could i go without having to modilfy other systems?

oh, this issue has been like this since I added the blower....I guess I see more and more SC'd tahoes on youtube now and it just started to really bug me today as I see how their trucks burn it up..

08cheyennesc

iTrader: (2)

What size injectors? You will need at least a 2800 stall converter to make the procharger happy, in running a 3.6 pulley on the 6 rib with no belt slip,also I installed a T on the BOV for the boost gauge.

Mangled03gmc

iTrader: (95)

Yes a T would be fine in any part of the vacuum lines.. Like said a bigger verter is a must imo to get these to shine.. Your running big wheels and tires also, so that is hurting you in the GO department.. You could pulley down to get more boost, it would make a diff, but then again you would prob need some tweaks in the tune, to make the best of it..

AgFormula02

iTrader: (9)

There is a section in the tune related to how much the TB opens based on rpm and pedal angle. Baiscally, you can mash the gas, but may only open the TB to 35% until 1800 rpm, or 2500 RPMs. Maybe that?

mdelgado

They're the stock Flex fuel injectors, so I think 33lbs/hr

Where did you get your pulley?

jg53

iTrader: (10)

Call prochargers tech line. They will help you out.
If think a converter would help you out tremdously here.

Im running a similiar tire size as you, 285/50/20, and I have a problem with keeping the tires planted to the ground.

I have the stock pulley as well.

This is in a CCSB