TPI bolt pattern
Thread Starter
TGO Supporter
iTrader: (1)
Joined: May 2002
Posts: 2,480
Likes: 2
From: El Paso, Texas
Car: 1987 IROC Z
Engine: 350 TPI L98 block
Transmission: 700R4
TPI bolt pattern
So I've got 3 plenums going to an oven (cleaning, I forget what its called), and I took the bolts and sensors off of the plenum to have it cleaned, but I did not note the pattern. Does anyone have a picture of the bolt pattern for the runners to the plenum?
Its pretty much fool proof. The longest torqx bolts go backwards in the end of each runner. Depending on the year of the engine they came off of all the rest should be the same size. There might be 2 other bolts, one to hold the clip for the throttle/cruce cables and one that the alt. bracket hooks to.
No pictures but I took a look at the runners I took off this weekend.
There will be 4 quite long bolts, they go in the bottom flange, one at the foreward pair of tubes and one at the rear pair (there is a boss in that spot, you'll know it when you see it) The next longest bolts will be the ones that face backwards (2 of em) one at the foreward end of the right hand runners and one at the aft end of the left hand runners (both on the bottom flange).
On the left hand runners, top flange, center is the bolt with the clip for the throttle and cruise cables.
On the right hand runners foreward lower flange is the bolt with the stud in the head, this is for the alt bracket ('85 & '86 only).
Hope that is clear enough.
There will be 4 quite long bolts, they go in the bottom flange, one at the foreward pair of tubes and one at the rear pair (there is a boss in that spot, you'll know it when you see it) The next longest bolts will be the ones that face backwards (2 of em) one at the foreward end of the right hand runners and one at the aft end of the left hand runners (both on the bottom flange).
On the left hand runners, top flange, center is the bolt with the clip for the throttle and cruise cables.
On the right hand runners foreward lower flange is the bolt with the stud in the head, this is for the alt bracket ('85 & '86 only).
Hope that is clear enough.
No Offense, But if you can't figure this one out on your own, you probrably shouldnt have taken them off in the first place 
Ill Give you a Hint Tho,
The Threaded end of the bolt, Matches the Threaded part of the hole. Those Holes in the Top Of the bottom Flange of each runner that are threaded... Those bolts thread in from the Intake side
Be Sure to report back to us on how this project turns out, Many others are awaiting your success...

Ill Give you a Hint Tho,
The Threaded end of the bolt, Matches the Threaded part of the hole. Those Holes in the Top Of the bottom Flange of each runner that are threaded... Those bolts thread in from the Intake side

Be Sure to report back to us on how this project turns out, Many others are awaiting your success...
Thread Starter
TGO Supporter
iTrader: (1)
Joined: May 2002
Posts: 2,480
Likes: 2
From: El Paso, Texas
Car: 1987 IROC Z
Engine: 350 TPI L98 block
Transmission: 700R4
If I had the plenums in front of me, I probably could. I took the bolts off in a rush as time was not on my side. I did not realize that they were different sizes until just recently... bare with me. Additionally, I am usually the type to pay extreme detail to these things. That I did not this time is surprising even to me.
Thread
Thread Starter
Forum
Replies
Last Post
evilstuie
Tech / General Engine
22
Jan 9, 2020 08:29 PM
ambainb
Camaros for Sale
11
Apr 25, 2016 09:21 PM
Sanjay
Engine/Drivetrain/Suspension Parts for Sale
1
Aug 12, 2015 03:41 PM





