Intake manifold help

[kb3]

I can't seem to install the lower intake on the 5.0 motor without getting vacuum leaks. It is a Ford Motorsport Cobra EFI intake. Aluminum intake to aluminum heads. Any advice on getting it to seal better when I reinstall would be great.

 

[B67FSTB]

where does the vacuumleaks occur?at the cilinderheads or front/rear seals?

 

[kb3]

it appears that most of the leaks are where the intake manifold meets the heads. I am buying another set of gaskets and trying again. I am not certain the gaskets did not slip toward the valley when the intake when on.

 

[stangg]

I'm pretty certain I used Fel-pro 1262 intake gaskets. If I remember right it has the print-o-seal on both sides of the gasket. If you've got some longer 5/16-18 bolts or threaded rod, you can thread them into the 4 corner holes to serve as alignment pins and hold the gasket in place. Once the manifold is in place just unthread the alignment studs and replace with the mounting bolts.

 

[66gt350]

Have you checked both surfaces with a mechanic's flat edge to make sure that you don't have any warpage?

 

[kb3]

I'm pretty certain I used Fel-pro 1262 intake gaskets. If I remember right it has the print-o-seal on both sides of the gasket. If you've got some longer 5/16-18 bolts or threaded rod, you can thread them into the 4 corner holes to serve as alignment pins and hold the gasket in place. Once the manifold is in place just unthread the alingment studs and replace with the mounting bolts.

That is a great idea on the studs....off to the parts store!

 

[kb3]

Have you checked both surfaces with a mechanic's flat edge to make sure that you don't have any warpage?

I did not check the surfaces this last time since the heads and manifold are new. But when I take it apart tonight, you can trust that I will do it for certain. The motor and the manifold are Ford Motorsport items so I thought they would be in good shape, although the manifold is from China :censored

 

[Anonymous]

I'm pretty certain I used Fel-pro 1262 intake gaskets. If I remember right it has the print-o-seal on both sides of the gasket. If you've got some longer 5/16-18 bolts or threaded rod, you can thread them into the 4 corner holes to serve as alignment pins and hold the gasket in place. Once the manifold is in place just unthread the alingment studs and replace with the mounting bolts.

I use these: http://www.summitracing.com/parts/FEL-1262S3/ and haven't had any leaks. Def use the guide posts when installing the intake!

 

[apollard]

Also, if the heads have been shaved or the block decked, the intake may need machining also. Check how the intake & heads meet w/o a gasket - the two surfaces should be very close to parallel.

 

[kb3]

Thanks for all the help! I had a buddy come over and we got it set right this time. Liberal use of gasgacinch, studs and RTV and all is good. No vacuum leaks, steady 14-15" of vacuum.

 

[B67FSTB]

Let the RVT dry out for a day or so , to harden out.