txaggie
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454 engine rebuild and intake gasket leak
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txaggie
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Went with this as a replacement order today:
www.summitracing.com
Fel-Pro 1212 S-3 Fel-Pro Performance Intake Manifold Gasket Sets | Summit Racing
Free Shipping - Fel-Pro Performance Intake Manifold Gasket Sets with qualifying orders of $109. Shop Intake Manifold Gaskets at Summit Racing.
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Typically with used heads and/or intake, it's best to smear a very thin coating of rtv around the coolant ports, to prevent minor leaks like that.
txaggie
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the heads were cleaned and machined, all new gaskets everywhere, and a new edelbrock air gap intake. I’m about to go retorque everything because we haven’t checked that post heat cycles. Wonder if that could be it?
txaggie
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Bolts were really loose. Some were down to only 5 foot pounds when spec is 25. Hopefully it solves it.
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Hopefully the intake face of the heads were not machined as that can make it more likely for the intake to have fitment issues.
hogdaddy
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Edelbrock and many others recommends a non-steel core gasket for use with aluminum intakes as the low torque of the bolts does not sufficiently compress the steel core gasket.
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75gmck25
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I also found that the old bolts for my stock intake on an SBC were just a little too long for the thinner flange on the intake. I'm not sure how the BBC compares.
Some of the SBC bolts (center?) go through the head into the valley, so no issue other than making sure they have RTV to stop oil weeping. However, IIRC the four end bolts on the SBC are into a blind hole, and if the bolt is too long it may bottom out and give you a false torque reading before it completely compresses the intake gasket. In my case it was the bolts nearest the firewall that led to a small loss of antifreeze, which finally turned into a stream.
Some of the SBC bolts (center?) go through the head into the valley, so no issue other than making sure they have RTV to stop oil weeping. However, IIRC the four end bolts on the SBC are into a blind hole, and if the bolt is too long it may bottom out and give you a false torque reading before it completely compresses the intake gasket. In my case it was the bolts nearest the firewall that led to a small loss of antifreeze, which finally turned into a stream.
