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Discussion Starter · #1 ·
truck was stock and towed great.

now...
added 100plate / added boost nipple that comes with it
Straight pipe
big filter
guages (boost, EGT)


With the 100 plate between all the way forward and stock location I have WAAAAY too much egt. At 70 mph I have MAYBE 2lbs of boost and 1000 - 1100 degees egt. Lots of smoke at times. If I hammer it, in 5th gear I will hit 30lbs at the upper most rpm, but EGT's will goto 1400.

with these symptoms I think maybe I have a boost leak from the install. So I block off the turbo inlet with some pvc + coupler and bump air into the system from the boost reference for the guage. Holds the air just fine.

Now I am stumped.

Why no/to little boost while at cruise (with or without trailer). I assume that is the cause of my EGTs.

Any suggestions?
 

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turn that timing up. that will spool your turbo up a lot faster and get rid of those nasty egts.
 

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Discussion Starter · #3 ·
I assume 15 degrees? What's stock?

my buddy's 2000 24v with equiv mods makes 15lbs while cruising at 70mph.

How much boost should I make at 70mph unloaded?
 

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15* - 16*... It's a pain in the arse to do it yourself..

And your boost numbers sound about right... Cruising = no added(accelerating) fuel in the system.. No added fuel = less exhaust pressure = low boost PSI. Pretty normal... And honestly, I've seen my pyro go past 1400 a few times... It's not GOOD for it, but keep your eye on it and you'll be fine. Keep your manifold in check.. If you see it start warping, get a 3 piece and go on with it.
 

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I am not sure what its supposed to be at I think about where mine is or atleast for good mileage it is. crusing 70 I am at 6psi and 650EGT.

Seems high to me even when mine was stock other then 0 plate I still ran about 6psi and 700EGT at 70 if I hit the gas it would barry the gauge at 1500
 

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Just checked my 98 on the way to work this morning. 70 on the speedo, running 8psi and 600-700 on the pyro. What rear end is in your truck?
 

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Discussion Starter · #7 ·
Just checked my 98 on the way to work this morning. 70 on the speedo, running 8psi and 600-700 on the pyro. What rear end is in your truck?
4.10 gears

at 70 I'm 0 to 2lbs of boost.

Could it be a turbo issue?
 

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I assume 15 degrees? What's stock?

my buddy's 2000 24v with equiv mods makes 15lbs while cruising at 70mph.

How much boost should I make at 70mph unloaded?
two VERY different trucks, that'd be like me comparing my 24 valver with a CR....:doh:
 

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two VERY different trucks, that'd be like me comparing my 24 valver with a CR....:doh:
Yeah, exactly... Plus, with the 4.10 rear end, at 70 you'll be at a higher RPM than mine will.. Your boost numbers should be higher than mine. You're getting zero pounds of boost on the gauge??
 

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Discussion Starter · #10 ·
thankyou for the clarifacation. Any insight on my egt / lack of boost problem?
 

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My 97 with 4.10s runs 700ish for egts and 10-15 lbs of boost at 70. Before the cam it was only 6-8 lbs of boost and about 800ish for egts cruising. It sounds like you might have a boost leak somewhere check the passenger side lower intercooler boot, mine was leaking and after a new set I gained about 4-5 lbs of boost all the time.
 

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yup, check the boots, those lil SOB's like to get pinched:thumbsup:
 

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If you're going to go to the hassle of checking them, you might as well fix them. Pull 'em off, spray some hair spray on the intercooler and put them back on. Will take an 11mm deep socket to loosen the clamp.

Boot = hard plastic coupler from intercooler to turbo piping..
 

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Discussion Starter · #15 ·
will try that next.

How many are there?


I've got 2 other turbo cars currently and other turbo cars yrs past. Never heard the term boots. Always been silicon couplers or intercooler couplers. No worries. Just different terminology.
 

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If you're going to go to the hassle of checking them, you might as well fix them. Pull 'em off, spray some hair spray on the intercooler and put them back on. Will take an 11mm deep socket to loosen the clamp.

Boot = hard plastic coupler from intercooler to turbo piping..
on my 24 valver, they are soft plastic...:doh:

i can actually crush the one on the drivers side by pushin it in with my hand, is this bad...:confused013:
 

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We drive Cummins... don't have any use for $5 words. lol. Just check ALL the connections on your turbo piping.. Or, to get real fancy... "test your intercooler couplers". lol!!!
 

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They're four of them two on each side of the intercooler. The one on the passenger side at the intercooler kept blowing off on mine at 10 lbs of boost. Yes they are silicone couplings.
 

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Discussion Starter · #19 ·
I will check them tonight. I have my doubts it is them since the boost leak test was successful.
 

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why are you going to try to fix boost leaks that aren't there? :confused:

if you have no boost leak, you could either have a turbo that's got excessive clearance between the compressor wheel and housing, a wastegate puck that's hanging open for some reason, or the truck might be running just fine. did you get an adjustable boost elbow or one with a fixed orifice? bump the timing to 16* and bump the boost to 35psi, and I bet you drop 200* EGT
 
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