Help! Runner bolt size question.
Thread Starter
Instructor
Joined: Mar 2006
Posts: 111
Likes: 0
From: San Antonio Texas
Help! Runner bolt size question.
Hoping someone can help. I have just finished replacing the fuel injectors, getting ready to assemble everything and have lost my cheat sheet that labeled what bolts go where. 
These are the black torx head bolts on the runners. If anyone else is doing a similar project, I would appreciate some info. I have a good idea of what goes where and started to put it back together, but have second thoughts on what might happen if I put them on wrong. Thanks in advance.
These are the black torx head bolts on the runners. If anyone else is doing a similar project, I would appreciate some info. I have a good idea of what goes where and started to put it back together, but have second thoughts on what might happen if I put them on wrong. Thanks in advance.
Team Owner
Joined: Jan 2003
Posts: 20,299
Likes: 240
From: Summerland B.C. Canada
It's been some time since I removed mine, but I don't recall too many options. How many different lengths are there ? There are 2 long ones that go in from the manifold into runners and maybe another different length for cold start valve ??
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
I am thinking there might be three different length bolts. The longest ones go where AGENT 86 described (intake manifold to runner). Pay attention and you will notice on the runners that the flange is a bit thicker on the bottoms...on a few. The next longer ones go there.
Remember to hand start these bolts as they go into aluminum. Leave all the bolts loose until all are started (use antiseize on the threads). If you notice one is getting harder to tighten and there is more thread left....that bolt is in the wrong place or the threads are al goobered up.
Remember to hand start these bolts as they go into aluminum. Leave all the bolts loose until all are started (use antiseize on the threads). If you notice one is getting harder to tighten and there is more thread left....that bolt is in the wrong place or the threads are al goobered up.
Thread Starter
Instructor
Joined: Mar 2006
Posts: 111
Likes: 0
From: San Antonio Texas
I have three different sizes. I think the longest ones were for the manifold to runner. It didn't occur to me to place them in and check if there was any thead left. I will give it a go and re post.
Thread Starter
Instructor
Joined: Mar 2006
Posts: 111
Likes: 0
From: San Antonio Texas
Ok, I learned that the full threaded bolts go the throttle body. I still mixed some up between the fuel rail bolts and the runners. It seems to work. Would like to get a hold of some kind of diagram.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
The 4 fuel rail bolts are the 10mm non-Torx; can't help on sorting out the runner bolts since my FSM doesn't list sizes.
As an aside for future work, put bolts into zip-loca bags and label the bags; makes the assembly go much smoother.
As an aside for future work, put bolts into zip-loca bags and label the bags; makes the assembly go much smoother.
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Top of runners into plenum:
(7) M8x30
plus the special bolt with throttle cable holder.
Bottom of runners into intake baseplate:
(4) M8x55 underneath each runner pair between tubes.
(6) M8x30 at each end of the runner flange, and one in the middle
(2) M8x40 go into the backside of the runner flange, you have to do these from the opposite side of the motor.
Fuel rail:
(4) M8x35 bolts from the top
(2) M8x20 on the little flange in front of the intake.
I'm ashamed to say I have these all memorized.
(7) M8x30
plus the special bolt with throttle cable holder.
Bottom of runners into intake baseplate:
(4) M8x55 underneath each runner pair between tubes.
(6) M8x30 at each end of the runner flange, and one in the middle
(2) M8x40 go into the backside of the runner flange, you have to do these from the opposite side of the motor.
Fuel rail:
(4) M8x35 bolts from the top
(2) M8x20 on the little flange in front of the intake.
I'm ashamed to say I have these all memorized.
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Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
While we're at it...
TB = (4) M8x70
Throttle bracket = (3) M6x12
Distributor cover & TB plate = (9) M4x12
Intake base = (12) 3/8-16x1"
L98 Tstat = (2) 3/8-16x1.25"
EGR = (2) 5/16-18x1"
Perimeter VC's = (8) 1/4-20x1"
centerbolt VC's = (8) 1/4-20x3.5"
TB = (4) M8x70
Throttle bracket = (3) M6x12
Distributor cover & TB plate = (9) M4x12
Intake base = (12) 3/8-16x1"
L98 Tstat = (2) 3/8-16x1.25"
EGR = (2) 5/16-18x1"
Perimeter VC's = (8) 1/4-20x1"
centerbolt VC's = (8) 1/4-20x3.5"
