Intercooler slows me down!

[gotoy]

After reconnecting my intercooler I note a loss of pwer in my engine!! Why??
Also prior to reconnection my boost would show 11psi...now its down to 7.5
I understood I would have an increase in power..not a decrease

[plowy]

were is the boost guage plumb into at the manifold after the intercooler

or on the turbo side before the cooler

it seems as if it is the first option , and your dropping a bit of boost as the turbo isn't a straight feed to the turbo anymore
now it has to work a little harder to feed the air threw the extra plumbing and cooler
sounds like you need to adjust the boost to compansate for the extra plumbing
i may be wrong

[Axel Von Gardan]

Maybe the cooler is just TOO BIG?
Is it wide as allmost the whole car?
Too big cooler don´t increase power, it looses it.
How big it is?
And what kind of turbo you have?Stock?
Edit:Diesel or petrol engine?
Or what kind of car you have?

[Skip]

Thats incorrect. The bigger the intercooler the colder the air and the more power you can make, what a larger intercooler causes is more lag or response time as there is more volume the turbo needs to fill before reaching the engine.

a 3.5 psi drop sounds too much, 1 psi is about the most you would get unless the intercooler is significantly undersized. I would suggest you check all your hoses for boost leaks first, this sounds the most likely cause of the problem.

[Shadow]

yep sounds like an air leak. had same problem on my sisters 180sx, pain in the arse to find, ended up just replacing all hoseclips and that fixed it

[carts]

If anything, I would suggest the intercooler is too small, thus is too restrictive.

It sounds like your waste gate actuator is plumbed pre intercooler. If you plumb it post intercooler, your turbo will have to work harder to get the psi your waste gate is set at.

[dow50r]

easy way to fix this is move the pressre sensing hose for the waistegate to after the cooler, so it compensates for the extra plumbing...turbo will boost till manifold down stream is spec instead of turbo upstream of cooler
Andrew

[Skip]

easy way to fix this is move the pressre sensing hose for the waistegate to after the cooler, so it compensates for the extra plumbing...turbo will boost till manifold down stream is spec instead of turbo upstream of cooler
Andrew

And you will wear the turbo out quicker cause it is turning much harder than it should. The easy wasy to fix would be to fix up your apparent boost leak.

[Ruffy]

Could have a leak in the intercooler.

[gotoy]

The engine is a 2LT non electronic type. Th eintercooler is mounted downstream of the turbo. The outlet of the intercooler goes direct to the engine air intake. The hoses and clips are brand new, proper ones too not just rubber hoses.

Anybody have a diagram/drawing of how it all should be set up?

[Dingo]

Is the intercooler a topmount or frontmount,
what is the diameter of the inlet and outlet spigots on the intercooler, exactly how big is the intercooler L x W x H.
What size hoses are you using

All these things contribute to the effeicency of it.

On a good setup you shold only notice about 1 - 1.5 boost loss from standard. Which is then gained back via a boost controler or biger turbo or Hi-flow the one you got, but with bigger turbo you lose bottom end power.

[gotoy]

Is the intercooler a topmount or frontmount,
what is the diameter of the inlet and outlet spigots on the intercooler, exactly how big is the intercooler L x W x H.
What size hoses are you using

All these things contribute to the effeicency of it.

On a good setup you shold only notice about 1 - 1.5 boost loss from standard. Which is then gained back via a boost controler or biger turbo or Hi-flow the one you got, but with bigger turbo you lose bottom end power.

Intercooler is top mount with a scoop avbove it.
Inlet and outlet spigots are 2 1/4".
Intercooler size L 400mm, W 275mm, H 50mm.
Using 4 hoses and two pipes at 2":
Hose turbo to 2" pipe...hose 2"
Pipe to inlet turbo..hose 2" to 2 1/4"
Outlet turbo to engine air intake hose 2 1/4" to 2.5".

[Skip]

All sounds fine to me. Id say you still air loosing boost through a leak somewhere, perhaps it's the intercooler as Ruffy suggested. Just because you have "proper" hoses doesn't mean they are tightened up correctly.