Ok, so Im gradually fixing the problems with my car. But now next up to bat is my boost problem.

So say Im in 4th on the highway and go wot. Im spooling, 7psi by 4k rpm, 17 by 5k, then at the vtec crossover at 5400, boost goes way down to 11-12psi and holds steady.

Then say I want 15psi in vtec, it goes to like 19 first, then 15.

So, wtf. I just changed wastegate spring from a .3 bar to a .8 bar I believe in hopes of a stronger spring will hold, but alas, no avail.

My wastegate is a 35mm Tial and its on an elbow off my Inline Pro manifold. I cant figure this out.

Helppppp

EDIT: Boost controller is a Greddy Profec B


Modified by SpeedingHatch at 3:00 AM 6/7/2006

 

Sounds like it's the boost controller-- never messed with one, but I know they have a lot of different settings to play with.

 

you gotta mess around with the gain on the controller

 

sounds like the the spring is slipping the same thing was happening to me

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tcontesh &raquo;</TD></TR><TR><TD CLASS="quote">sounds like the the spring is slipping the same thing was happening to me</TD></TR></TABLE>

how does a spring "slip"

 

it can happen with a manual boost controller, I meant boost creep

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tcontesh &raquo;</TD></TR><TR><TD CLASS="quote">it can happen with a manual boost controller, I meant boost creep</TD></TR></TABLE>

uhh but he doesnt have a manual boost controller

 

Yeah sorry prolly should have read that

 

its not creep, its loss.

Like, it spools nice and evenly and holds 17 before 5400, then at the crossover, drops instantly to 12 and holds 12 till redline.

wtffffffffff

 

what engine management do you have? f it is not the boost controller check you timing.

 

BOV leaking???

 

does it hold boost fine if u take out the boost controller?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b18ccivics &raquo;</TD></TR><TR><TD CLASS="quote">what engine management do you have?</TD></TR></TABLE>

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b18ccivics &raquo;</TD></TR><TR><TD CLASS="quote">what engine management do you have? f it is not the boost controller check you timing.</TD></TR></TABLE>

Timing is good. Engine management is Zdyne.

With the boost controller off, it still does it

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SpeedingHatch &raquo;</TD></TR><TR><TD CLASS="quote">Timing is good. Engine management is Zdyne.

With the boost controller off, it still does it </TD></TR></TABLE>

Update: With the boost controller completely tuned off, the boost holds

 

odd lol i would just mess with the settings, cause that really shouldnt happen lol as if you didnt know that

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Soccerking3000 &raquo;</TD></TR><TR><TD CLASS="quote">odd lol i would just mess with the settings, cause that really shouldnt happen lol as if you didnt know that </TD></TR></TABLE>

Im starting to think its anything past 15, it dropps.

I will mess around with it tomorrow and report back the highest psi I can get without it tapering off

 

Hm odd, I know three people who use the profec-B over 15psi and have no issues, they actually love how easy and precise it is.

 

Im going to switch some vaccum lines around and then cruise. Results in a few

 

So I seem to have fixed it by switching the vacuum lines around.

One part of the greddy box was T'd to the bov vaccum line off of the manifold, and the other straight of the mani. So I put the bov one by itself and T'd the "in" and "out" of the greddy box to its own source.

Seems to hold well.

Yay