Intake manifold bolt HELP HELP!!!!
Thread Starter
Racer
Joined: May 2004
Posts: 385
Likes: 1
From: Olalla Wa
Intake manifold bolt HELP HELP!!!!
AH NUTS!! Does anyone know where the 4 1-1/2 bolts go on the manifold? When I took it off I never noticed that there were 2 sizes the 1-1/4 and the 1-1/2. Well here I am ready to put the thing back together and now mister stupid doen't know what to do 
Please someboby HELP I want to finish this thing!! 
Thanks guys 
Please someboby HELP I want to finish this thing!! Thanks guys
Thread Starter
Racer
Joined: May 2004
Posts: 385
Likes: 1
From: Olalla Wa
65zo1-No I'm ready to put the manifold back,so I'm talking about the bolts into the heads.I was at least smart enough to mark the runner to manifold bolts when I took them out,and was aware they were different sizes,but had no idea the manifold bolts were also different sizes as well, so now I'm S.O.L !! This is just got me PISSED!! Would they be the four corner bolts do ya' think??
Last edited by myblue91; Jul 29, 2005 at 10:47 AM. Reason: More info
Racer
Joined: Aug 2004
Posts: 377
Likes: 1
From: Redmond Wa
On my '91 the 1 1/2" bolts went in the four outter most bolt holes in the manifold.
For example... X x x x x X Driver side where the big X is the 1 1/2"
X x x x x X Passenger side where the big X is the 1 1/2"
I know this since I drew a picture of where the bolts went when I did mine last December.
Good luck.
For example... X x x x x X Driver side where the big X is the 1 1/2"
X x x x x X Passenger side where the big X is the 1 1/2"
I know this since I drew a picture of where the bolts went when I did mine last December.
Good luck.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
'91 and current production heads are counterbored at the front and rear intake manifold bolt holes for gasket retainers. Longer bolts go there, though the shorter ones seem to work (at least for me) without any problems. GM no longer makes the longer bolts - at least my supplier couldn't find a current part # for them. The old part # is given in the Service Bulletin outlining the new design.
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Thread Starter
Racer
Joined: May 2004
Posts: 385
Likes: 1
From: Olalla Wa
Manifold update
OK, just put the manifold on torqued to GM specs. and will go back in awhile to retorque. Now to 65Zo1- live and learn I guess, when taking out the bolts that 1/4 in. is sure not noticeable.I went" Holy Crap" when I took them out of the bag to clean them. And, SunCr I got Fel-Pro gaskets from Summit Racing. They're no retainers on these,but used the Tech Tip by Jake,and used a thin layer of permatex copper laden stuff which held the gasket on real well!! I was shaking so bad had to pull back a few times before I just got the b@$#s to drop it on. Now it's cross the fingers,check for leaks. Thank you all for your help Grace91-I'll buy ya' a root beer if I can ever make it up there with those XXX Root Beer guys That copper "stuff" is an idea from Bogus who had suggested I spray a coat of a copper something(Sorry Bogus,I forgot what it was) on the head and gasket.I'm glad to be rebuilding ,instead of tearing down!
Grace91-I'll buy ya' a root beer if I can ever make it up there with those XXX Root Beer guys That copper "stuff" is an idea from Bogus who had suggested I spray a coat of a copper something(Sorry Bogus,I forgot what it was) on the head and gasket.I'm glad to be rebuilding ,instead of tearing down!
Racer
Joined: May 2004
Posts: 476
Likes: 0
From: DFW TX
Originally Posted by 65Z01
Hmmmm, maybe '90 & '91 differ from '88...or maybe I just didn't notice???
Anyway, my base doesn't leak and I've just learned something new this morning.
Anyway, my base doesn't leak and I've just learned something new this morning.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
Unless you've swapped out to current production 113's (or someone slapped a V6 in it), '91 is the only V8 with different intake manifold bolts and gaskets. From the Bulletin, GM was experiencing a large # of coolant leak complaints and they determined that the gaskets weren't maintaining alignment during assembly or repair. In addition, if it went on for any length of time, the manifold and heads were getting pitted by galvanic corrosion, so their warranty claims entailed a lot more than just new gaskets. The new design ensured a better alignment on the production line and was adapted for all most every engine they produced (that had coolant flowing through the manifold with the 6's getting rubber seals to boot). The bolts were different lengths because the retainers sacrificed a couple of mils of the threads and to maintain claimping forces, you got a longer bolt.
