Intake Manifold

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Jun 28, 2001 | 11:24 AM

IROC-Z_85

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Joined: Mar 2001

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From: Some City, OR

Intake Manifold

Well in another post I just mentioned that I'm installing a new cam. Thus everything is torn apart. So what I'm wondering is what is the most restrictive places in the intake manifold to port, is it anything like the plenum with two obvious spots that need improvement, or is the general idea to widen the whoooooole port. I dont mind touching it up with a grinder while its off, but I want my car back on the road by saturday and I only have weekends to work on it. If anybody has any good manifold porting info please help me out, thanks.

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1985 IROC-Z, nuff said :P

Jun 28, 2001 | 03:43 PM

IROC-Z_85

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Member

Joined: Mar 2001

Posts: 254

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From: Some City, OR

Also:

160 or 180 thermostat?

Im thinking 180

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1985 IROC-Z, nuff said :P

Jun 30, 2001 | 09:04 AM

MikeInAZ

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Joined: Oct 1999

Posts: 735

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From: Portales, NM USA

Car: 86 T/A

Engine: 5.0 TPI

Transmission: 700R4

If you live in:

The Artic Circle - 195°
Cooler Climate - 180°
Warmer Climate - 170°
Hotter than Hell - 160°

Jun 30, 2001 | 11:36 AM

89gta383

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From: St. Augustine, FL

Car: 89 GTA

Engine: 383

Transmission: 4L80E

Axle/Gears: 12 bolt-3.73

You want to open up your lower intake as large as possible. You can hand port it, but it will take a lot of time. Extrude hone takes 3 weeks. I don't think the stock runners are thick enough for a lot of material to be removed. Get some large tube runners to help out with flow. The lower intake manifold is the most restrictive part of the tpi system. Try and open it up to 1.75 inches if you can, but then your runners will hold you back.