[CUMMINSSMOKIN]

so i installed my first set of gauges the other day and im not sure if its me or what but when i build boost it spikes up to 30 psi and slowly comes back down even we im still in the throttle.is this normal or could i have a leak somewhere. i checked the connections to the guages and no leaks.i did notice my intercooler boots are old and flimsy is it possible that that is the problem?

 

[CUMMINSSMOKIN]

bump please help:CRY::CRY:

 

[awenthol]

You sure it isn't just wastegating?

 

[CUMMINSSMOKIN]

well it could be but i wanted to hear some ideas on what some of thought.

 

[tramp_line_ape]

should just be wastegating. i had a leak in my line to my boost guage, and the needle fluttered and it woul only read about 75% of what i was pushing.

 

[Mopar1973Man]

Boost elbow or wastegate problem...

If you had a boost leak it would be constantly low pressure plus lots of good ol' black smoke...:w:

 

[clc]

As the truck accelerates in a given gear the engine load falls off as the engine winds past its peak power so the boost creeps down. If you pull a load up a long uniform hill with a high throttle setting and a steady speed the boost should stay steady.

If you manage to hold 30 PSI of boost you need to check the pyrometer. Your EGTs could be getting high.

 

[CUMMINSSMOKIN]

oh ok guys thanks for the info i just wasent sure

 

[clc]

Did the truck have a problem or was it just behaving as I described in my first sentence?

 

[BigBlue]

It's just the wastegate on the turbo opening up. What's happening is that your spooling it up so fast that the gate can't open up fast enough to control the boost. Hence the spike. Then when the wastegate catches up and opens up is when you see the boost fall back down. FYI, you should be seeing more than 30psi though unless you don't have a boost elbow or turn buckle on the turbo.

 

[CUMMINSSMOKIN]

yea i dont have a boost elbow but im gonna make a adjustable one here soon.