86 Plenum Thickness?
Thread Starter
Burning Brakes
Joined: Nov 2003
Posts: 1,234
Likes: 5
From: Herriman UT
86 Plenum Thickness?
I need to remove some material from the underside of the plenum in the area of the EGR valve (Clearance issues with large tube runner install). How much material can I safely remove?
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
not much.... 1/8" max.... you may want to see if you can remove some material from the EGR valve...
perhaps thin down the mounting base? I donno... how much do you need?
My bigger concern is why must you grind anything... those aftermarket tubes shouldn't effect anything.
perhaps thin down the mounting base? I donno... how much do you need?
My bigger concern is why must you grind anything... those aftermarket tubes shouldn't effect anything.
Thread Starter
Burning Brakes
Joined: Nov 2003
Posts: 1,234
Likes: 5
From: Herriman UT
The plenum clearly sits lower with the large tubes than with the stock runners, thus the interference. 1/8" Just might do it, though. Jim @ TPIS says he's never run accross this before. Maybe it's just an oddball set of runners. Probably not much I can do with the EGR valve.
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
Yea, something's definitely wrong. Those runners should not cause any interference with the EGR and the plenum shouldn't sit any lower either.
Who's runners are they?
I'd send them back to have them checked.
As far as the EGR itself, you can remove it, install a cover plate to block the hole and have it turned off in the PROM. That's what I did on my 86.
Jake
Who's runners are they?
I'd send them back to have them checked.
As far as the EGR itself, you can remove it, install a cover plate to block the hole and have it turned off in the PROM. That's what I did on my 86.
Jake
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
Originally Posted by geezel
TPIS runners.
If not, I'd send them back to TPIS to be checked. You may have been sent the wrong ones.
I don't know where the EGR mounts on other years/models, but could they be for an 'F' body?
Jake
Drifting
Joined: Mar 2005
Posts: 1,923
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From: GA
Originally Posted by geezel
The plenum clearly sits lower with the large tubes than with the stock runners, thus the interference. 1/8" Just might do it, though. Jim @ TPIS says he's never run accross this before. Maybe it's just an oddball set of runners. Probably not much I can do with the EGR valve.
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Thread Starter
Burning Brakes
Joined: Nov 2003
Posts: 1,234
Likes: 5
From: Herriman UT
I bought them from another Forum member who claimed TPIS Part no. 500-503 which their catalog says is good for 85-88. The interference is at the top of the EGR valve / bottom of plenum. I'll do more investigation after the long weekend.
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
Originally Posted by geezel
I bought them from another Forum member who claimed TPIS Part no. 500-503 which their catalog says is good for 85-88. The interference is at the top of the EGR valve / bottom of plenum. I'll do more investigation after the long weekend.
Jake
Thread Starter
Burning Brakes
Joined: Nov 2003
Posts: 1,234
Likes: 5
From: Herriman UT
All I can say at this point is that they are LONGER as measured along the outside radius of the tubes. I suspect a tighter radius would be tough to detect by eye, but the interference tells the story about the final height of the plenum.
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
Originally Posted by geezel
All I can say at this point is that they are LONGER as measured along the outside radius of the tubes. I suspect a tighter radius would be tough to detect by eye, but the interference tells the story about the final height of the plenum.
For example, if you take a coffee cup and set it on the counter. Then take another coffee cup, turn it upside down and set in on top of the first cup.
Using one of each, align the bolt holes on one end and see if they still align on the other. Or try measuring the distance between one upper bolt hole and one lower bolt hole on the stock runners. Then do the same on the other TPIS runner. See if there's a difference.
I'm just brain-storming this problem trying to visualize a way to detect the difference between the two.
Jake
Instructor
Joined: Aug 2004
Posts: 109
Likes: 3
From: Just North of Boston Mass
www.hotrodlane.cc has a nice egr blockoff plate.
I even passed emissions without the EGR.
http://www.hotrodlane.cc
I even passed emissions without the EGR.
http://www.hotrodlane.cc