Guys I need your help... My setup is a 00 Civic SI b16a2 with a Precision SC50 .63a/r and a 35mm Tial w/g that's set for 6.5psi and a Drag manifold. When I give it full throttle I show .7 bars(about 10psi), which is what I want. But all the sudden at 7500 to 8000rpm redline it goes up to 1.1 bar(about 15.5psi) What's going on? Is it my Wastegate and why? My Drag manifold? It's never done this before!!! Please Help

 

drag manifolds are notorious for boost spike from what i hear. that's why i didn't buy one, and bought an inline pro instead. i hope you get your problem fixed soon

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ha illuminato un &raquo;</TD></TR><TR><TD CLASS="quote">drag manifolds are notorious for boost spike from what i hear. that's why i didn't buy one, and bought an inline pro instead. i hope you get your problem fixed soon</TD></TR></TABLE>
Yea that's what I heard, but it didn't do it before

 

try porting out the wastegate hole in the manifold maybe?

liam

 

Anybody else that could help me?

 

All the members on H-T and I get 2 replies... come on guys help me out

 

i ported the wastegate and what kind of wg you got? mine doesnt spike with open dp.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by InTeGrA B18b1 &raquo;</TD></TR><TR><TD CLASS="quote">i ported the wastegate and what kind of wg you got? mine doesnt spike with open dp.</TD></TR></TABLE>

Tial 35mm w/g

 

my guess is he has a boost leak and its not building full boost until very late in the rpm band giving the illusion of boost creep.

 

Here's my (purely theoretical) response. From the research I've done, I think your boost creep is a property of your manifold design. When the wastegate is mounted to one primary pipe, instead of in the middle of the manifold, where all four primaries feed it equally, you get boost creep. This is because only the exhaust flow from the primary the WG is mounted to gets routed around the turbo through the WG. The other three primaries feed exhaust flow through the turbo, creating more boost. Think about it, if exhaust flow from all four primaries were to escape the manifold through the WG, three of the primaries' flow would have to go upstream of the primary the WG is mounted to. Make sense? As RPMs / flow increase, the placement of the WG on the manifold begins to limit the amount of exhaust flow that can bypass the turbo, which is what limits your boost.

I've heard Tial makes good WG's, so I don't think that's your problem. I think its time for you to get a manifold of better fundamental design. Anyone else agree?

- Jim

PS - In my opinion, this topic could have been named better. Hope this helps though, and good luck.

 

Thanks... That makes sense, but i just remember that my Tial gasket blew up. So I was wondering if there wasn't a tight seal and at high rpms the boost would leak out when i just use the tial with no gasket.... I just got my fire-ring so i should install it and see how it goes!!! Maybe that was the problem huh ?