3" downpipe require engine management?

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brodie.gordon
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3" downpipe require engine management?

Post by brodie.gordon » Fri Mar 27, 2015 2:42 pm

Currently running 3" from the mid pipe back and wondering if I go with a 3" downpipe will I need engine management? I was also going to install a new header because I think my current one is bad.

Running a td04, top mount intercooler and cone intake.

Thank you for any information and opinions on this.
1991 Legacy turbo

mike-tracy
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Re: 3" downpipe require engine management?

Post by mike-tracy » Fri Mar 27, 2015 3:26 pm

In my opinion and experience, the 3" pipes counterintuitively made my td04 spool up slower. And since I wasn't running the turbo over 12psi, the freer flowing exhaust's benefits were wasted. With a td05 and robtune, the stock exhaust choked, and the larger exhaust made it come alive.

So, imo, 3" pipes don't need engine management and made my car slower. On a larger turbo, Def upgrade the pipes and engine management.
1992 Legacy SS 5mt, build in progress
Josh Colombo wrote:
Mon Jan 14, 2002 10:23 am
Wait....I'm confused now.

brodie.gordon
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Posts: 60
Joined: Sat Apr 22, 2006 2:41 am
Location: portland, OR
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Re: 3" downpipe require engine management?

Post by brodie.gordon » Fri Mar 27, 2015 6:33 pm

Thank you. Sounds like I am good where I am at, haha.
1991 Legacy turbo

turbo970
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Re: 3" downpipe require engine management?

Post by turbo970 » Sat Mar 28, 2015 4:20 am

i run a full 3" tbe and my car seems more alive. my set up is a jdm td04 06 xt tmic fcd and running 14 psi

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