Siamesed TPI base manifold???
Thread Starter
Team Owner
Joined: Aug 1999
Posts: 24,017
Likes: 634
St. Jude Donor '10
Siamesed TPI base manifold???
I had heard something about this before. Has anyone here done it or have any info on it?
EDIT: I found all the stuff in the archives about it.
[Modified by SurfnSun, 12:59 PM 9/14/2003]
EDIT: I found all the stuff in the archives about it.
[Modified by SurfnSun, 12:59 PM 9/14/2003]
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: Siamesed TPI base manifold??? (SurfnSun)
This mod started a few years ago on the http://www.third-gen.org/ site; several guys here have also done it with success.
I have done this mod with good success; my L98 now pulls well through 5,800rpm. I believe I lost a little low end torque but it was hard to see even in 60' times; but I've more than compensated by installing a 2,000rpm TC.
There are dyno pulls before & after on my site (link in my sig. below) as well as some pics of this mod. Note that the "after" pulls were a little shakey due to a leaky fuel pressure gauge that was discovered only on the dyno; also, note that on the "after" pulls power is up by 10% (20hp) at 5,400rpm.
I have increased the siamese cut depth another inch for a total of 2" deep but don't have post mod dyno pulls yet.
I feel that with heads & cam this setup will pull into the 6,000rpm, at least that's the target.
I have done this mod with good success; my L98 now pulls well through 5,800rpm. I believe I lost a little low end torque but it was hard to see even in 60' times; but I've more than compensated by installing a 2,000rpm TC.
There are dyno pulls before & after on my site (link in my sig. below) as well as some pics of this mod. Note that the "after" pulls were a little shakey due to a leaky fuel pressure gauge that was discovered only on the dyno; also, note that on the "after" pulls power is up by 10% (20hp) at 5,400rpm.
I have increased the siamese cut depth another inch for a total of 2" deep but don't have post mod dyno pulls yet.
I feel that with heads & cam this setup will pull into the 6,000rpm, at least that's the target.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: Siamesed TPI base manifold??? (cdnguyred88)
looks like I've got a winter project to add to the ever growing list!!!!
Well sure, but think of all the "hours of fun" you'll have for under $100.....
:jester
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