Intercooler Effect on Boost

[**DONOTDELETE**]

Does an intercooler affect the boost for turbos? For example, you use a 5psi spring. Will the boost end up lower on the intake side? If it does, how do I calculate it?

Tim

[RPS13]

I think it depends on the size of the intercooler. The bigger it is, the more the boost will drop. I don't know how to calculate the loss though. I think the cores with the inner fins will offset some of the loss.

['97 S14 SE Turbo]

I would suggest to those who are interested in learning more about the basics of turbocharging to go pick up a copy of "Maximum Boost" by Corky Bell.

[**DONOTDELETE**]

A well engeneered intercooler will not loose much if not any boost, if U read Sports Compact Car- which U should, not some riceboy Super Honduhh (opps Super Street) magazine U would come to know that bigger is not always better, but in some case the big intercooler do not drop any boost. A well designed Sparco core will not loose any boost, it will be just as efficient as the small TTZ intercoolers, but with 4x its size, efficient meant as it will not loose boost. I recomend mouning the intercooler in a well ventilated area. My top mounted IC in my SE-R gets so hot that water can boil on it, why I THINK my head gasket is blown.

[**DONOTDELETE**]

SPARCO intercooler? Damn, their getting into everything huh? Just kidding Mike.

KF

['97 S14 SE Turbo]

That should've read spearco...

<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by fengkc:
SPARCO intercooler? Damn, their getting into everything huh? Just kidding Mike.

KF<HR></BLOCKQUOTE>

[**DONOTDELETE**]

Depends where you are getting your boost signal that opens the wastegate. If you have the signal at the turbo before the wastegate, the amount of boost you run will be you 5psi spring minus the IC delta (boost drop). If you are smart, you'd take the signal from the intake, so no matter what the delta, your intake (engine) will see 5psi.

regards,
s13turbo

['97 S14 SE Turbo]

I take mine from the Compressor outlet due to response purpose. Both methods work and are done for different reasons.

<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by S13TURBO:
Depends where you are getting your boost signal that opens the wastegate. If you have the signal at the turbo before the wastegate, the amount of boost you run will be you 5psi spring minus the IC delta (boost drop). If you are smart, you'd take the signal from the intake, so no matter what the delta, your intake (engine) will see 5psi.

regards,
s13turbo<HR></BLOCKQUOTE>

[RPS13]

I'm a little confused with S13Turbo's comment. Does he mean getting the boost signal before and after the intercooler? That's what I think he's trying to say or am I mistaken?

[**DONOTDELETE**]

If you take the signal(for the wastegate) from after the IC you engine will see 5psi witch is what is actually being delivered to the intake. This is how most factory turbo set-ups are designed. eg. Before the IC you might have 7psi after the IC you might have 5psi. If you take the signal from before the IC the intake might only see 3psi.

Now my question.. why is the BOV signal taken from the intake manifold? This is how my DET is set up. Is the BOV spring run off of negitive spring pressure or extreem barometric changes? anyone.

Mike
98 Sentra SE

['97 S14 SE Turbo]

It's run of the manifold pressure because when the throttle plate is closed, the pressure in the intake manifold will become negative. It is this negative/vacuum that is the muscle air that will help offset the spring tension in the BOV. If you route the signal/pressure line to the pressure side, you could turn the BOV into a surge valve where if the pressure exceeds what you wanted, the valve will open up. By putting the signal line to a source that will see vacuum will allow the BOV to stay closed during boost, and yet open up when the throttle plate is closed to act as a surge valve.

<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by 98SEDET:
If you take the signal(for the wastegate) from after the IC you engine will see 5psi witch is what is actually being delivered to the intake. This is how most factory turbo set-ups are designed. eg. Before the IC you might have 7psi after the IC you might have 5psi. If you take the signal from before the IC the intake might only see 3psi.

Now my question.. why is the BOV signal taken from the intake manifold? This is how my DET is set up. Is the BOV spring run off of negitive spring pressure or extreem barometric changes? anyone.

Mike
98 Sentra SE<HR></BLOCKQUOTE>

[benevolent]

<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by '97 S14 SE Turbo:
It's run of the manifold pressure because when the throttle plate is closed, the pressure in the intake manifold will become negative. It is this negative/vacuum that is the muscle air that will help offset the spring tension in the BOV. If you route the signal/pressure line to the pressure side, you could turn the BOV into a surge valve where if the pressure exceeds what you wanted, the valve will open up. By putting the signal line to a source that will see vacuum will allow the BOV to stay closed during boost, and yet open up when the throttle plate is closed to act as a surge valve.

<HR></BLOCKQUOTE>

ok...so who wants to come to columbus and run all my vacuum lines? and install the boost controller who's instructions are in japanese?