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302 Intake manifold bolt torque spec?

grs44310

Sr. Member
Joined
Feb 23, 2005
Messages
490
Loc.
Akron, Ohio
I'm attempting to solve an intake leak problem that I believe is keeping my engine from idling like it is supposed to. When I removed the manifold the bolts on the drivers side were barely finger tight. (Hummm, maybe that was my problem)

The Chilton's manual says to torque the bolts in two steps 50-60 ft lbs first in the sequence specified then 80-90 ft lbs in the same sequence. The problem is I have broken two different bolts now trying to get to the first setting of 60 ft lbs. Is this the right torque spec? What grade of hardware should I be looking for to replace my busted bolts?

Thanks,
Greg
 

airman

Contributor
Bronco Guru
Joined
Nov 26, 2003
Messages
1,838
I think it depends on the manifold and the bolt. I think those are 3/8 bolts and I doubt they are meant for that much.

I did mine to 28 ft lbs (it called for 25 but it seemed lite so in defiance...) and have no leaks. Just keep re-torquing in the same sequence intil they are set. I must have followed the sequence at least a dozen times to get them tight.

I also bought some good bolts from ARP and have an aluminum intake.

I think maybe the head bolts take the torque #'s that you mentioned above.
 

Cooter_76

Sr. Member
Joined
May 18, 2004
Messages
863
I was just looking for this info on the Edelbrock website yesterday. I beleive it said 18-24 ft. lbs.
 

IowaMike

Bronco Guru
Joined
Sep 7, 2001
Messages
1,260
Just did my 4 bbl intake last week, 18 - 24 as stated. The torques you listed look more like head bolt specs.
 

Paco

Full Member
Joined
Feb 4, 2005
Messages
293
Loc.
Pueblo, CO
In Chilton's book, #7140, pg.97, intake manifold specs 19-27 ft.lbs, depending on the year.

In Ford's 1974 truck shop manual, intake manifold bolt torque...20-22 ft-lbs
 
OP
OP
grs44310

grs44310

Sr. Member
Joined
Feb 23, 2005
Messages
490
Loc.
Akron, Ohio
Paco said:
In Chilton's book, #7140, pg.97, intake manifold specs 19-27 ft.lbs, depending on the year.

In Ford's 1974 truck shop manual, intake manifold bolt torque...20-22 ft-lbs

Ok that makes a heck of a lot more sense for a 5/16-18 bolt. Thank you for the help guys!
 
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