JayIntegra

Hey all, this is my first post. I've been trying to tackle a problem with boost spiking for a while but haven't had any luck. Someone recommended I ask on Honda Tech, so here I am! I'm sorry if this has been covered!

My current setup is as follows:

96 spec Integra Type R (Honda, not Acura, not sure if there's any difference)
TD05H-18G turbo
Custom manifold
38mm Tial wastegate (atmo venting)
390cc injectors
OBD1 ECU with Crome chip
3" undertank exhaust with generic 2.5" muffler

Basically i've been having boost creep issues from the start. When I was using the internal wastegate, the spring was set at 6psi, and it spiked to 10psi on cold nights (electronic boost cut was set at 10psi).
So I decided to get a custom manifold made up and use a Tial wastegate with a 7.25psi spring (I was assured it would hold the boost.) Unfortunately after getting the car retuned today it's even worse than before, and it hits the electronic boost cut a lot more than it used to.

So i'm trying to figure out how to control the boost better, and so far this is what i've come up with:

- Put a 5psi spring in the wastegate, so hopefully it doesn't let the boost spike so high
- or get an electronic boost controller (such as the Greddy Profec)
- or get a bigger wastegate that will flow better

Can anyone come up with any reasons why the wastegate won't hold the boost? Or does anyone have any suggestions to help control the boost?

187Chor

internal wastegates suck, but going to a higher psi spring dint make sense if u wanted less boostcreep.. then again a 5psi spring will also just be a bandade and not a solution to ur problem..

i am plannin on boosting my type r and am going to run a 44mm tial wastegate.. with small green spring.. i think its 5.85psi or something just under 6psi..

switch to 44mm, the better flow will fix ur boost creep problem, and even if it persists on the colder nites it might only be by 1-2psi..
theres no way to totally eliminate the boost creep on cold nites unless u wanna tune ur car on a cooler nite, but then during the day and in most warm weather ur car wont run like u tuned it.. its better the other way around..

blackeg

be careful with a 10 psi spike an 390cc injectors. im sure they are damn closse to capacity.


the better manifold is helping it creep. spike is when it jumps up right away or real quickly. creep is when it slowly keeps going up in boost wit the rpms. for example, my car with a 7.25 psi spring winds up making between 11 and 12 psi.


you could go with a 44mm wastegate. also try a new bc or no boost controller, shortening the wg vacuum line, or take it from a different source. also make sure its the only vacuum going from that line is to the wastegate, dont run other stuff off it