boost psi question
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From: Orange County, California
boost psi question
with my truck now running the 4x.014's, i'm only seeing 20psi max at what i believe is WOT. i believe i've heard that under stock fueling, these trucks are capable of 20psi. one thing i can think of would be to see if i'm reaching full throttle on the pump. if i am reaching full throttle, what could be the reason for only 20psi. i haven't molested my pump other than turning my fuel pin to the deepest side, but with larger injectors, i think i should be seeing at least a couple more psi. what are your thoughts?
my egt's are about where they should be. i didn't know what numbers to expect. but cruising about 45mph at 1750-1800rpm i was only seeing 600-700*. at highway speed approx. 72 or 73mph at 2300rpm they read about 800. if i stand on it in 6th up to about 2500rpm, they'd get to 1100*. so i seem to have enough air getting to the motor and could probably turn the power screw for a bit more fuel. no doubt the intercooler and 4" exhaust helps with the temps. i wish the old gauge was working when it had stock injectors and exhaust before i stepped up to the 4" and put the 4x.014's after the new head gasket. i would've liked to see the difference. oh well, at least i know i can't roast the turbo with my current setup. guess i'll have to wait to see what it reads when i can have a trailer/load behind me.
my egt's are about where they should be. i didn't know what numbers to expect. but cruising about 45mph at 1750-1800rpm i was only seeing 600-700*. at highway speed approx. 72 or 73mph at 2300rpm they read about 800. if i stand on it in 6th up to about 2500rpm, they'd get to 1100*. so i seem to have enough air getting to the motor and could probably turn the power screw for a bit more fuel. no doubt the intercooler and 4" exhaust helps with the temps. i wish the old gauge was working when it had stock injectors and exhaust before i stepped up to the 4" and put the 4x.014's after the new head gasket. i would've liked to see the difference. oh well, at least i know i can't roast the turbo with my current setup. guess i'll have to wait to see what it reads when i can have a trailer/load behind me.
You should have more than 20psi, possibly a boost leak somewhere. I have the Stage II Pin, Stock Turbo, 4" Exhaust, and Banks IC, and I get about 22psi. Check all the intercooler couplers and make sure they are tight.
Thread Starter
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Joined: Mar 2008
Posts: 4,389
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From: Orange County, California
i'll check all my clamps. hopefully a few are just loose. i'm also wondering if maybe my boost tube could have started to kink somewhere and it's holding back some pressure? i would guess that could give an improper reading as well.
You also might want to check the intercooler boots themselves for leaks. Roll them between your thumb and forefinger like you're rolling a smoke and feel for dry-rot and/or cracks and holes.
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Thread Starter
Registered User
Joined: Mar 2008
Posts: 4,389
Likes: 114
From: Orange County, California
just to clarify...the only mods done to my truck are as follows:
fuel pin at it's deepest side
4x.014's
banks (i think) intercooler kit
4" turbo back
low psi piston LP
i haven't tweaked on the pump yet but i should see more boost with the larger injectors period. i'm going to check for full throttle and replace the boots just so that i know they're new. if i'm still seeing 20psi, the intercooler will get pressure tested.
fuel pin at it's deepest side
4x.014's
banks (i think) intercooler kit
4" turbo back
low psi piston LP
i haven't tweaked on the pump yet but i should see more boost with the larger injectors period. i'm going to check for full throttle and replace the boots just so that i know they're new. if i'm still seeing 20psi, the intercooler will get pressure tested.
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