Hooker headers to AFR 225 heads major leaks!

[thehueypilot]

I bought some Hooker headers for my 93 Mustang Coupe (HOK-6228-1HKR) to bolt onto my AFR 225 heads and they leak real bad no matter what I do. I replaced to stock gasket (which leaked) with SCE copper gaskets and they leak even worse. Is their a trick to seal a twisted wedge header flange? These headers have a 2" diameter tube and are for twisted wedge heads but come with an adapter plate to bolt onto my AFR 225 heads. The leak occurs between the adapter and header flange only. Any help would be appreciated.

 

[90mustangGT]

Be sure the flange surfaces are flat. Maby try red silicone?

 

[thehueypilot]

Be sure the flange surfaces are flat. Maby try red silicone?

Thanks for the input. These headers are brand new and have about 15 minutes of actual idle time on them. They leak so bad the noise from the leaks drown out the actual sound of the exhaust note. It looks like the countersunk screws that hold the adapter plate on may be the source of the leaks. It looks like a really bad design if they expect me to seal on screw heads that are not flush (slightly below the surface) with the sealing surface? I will try silicone........

 

[FORCED2DV8]

I personally would not put any adaoter plate on a header, theyre usually a pain to make seal with just one gasket, Return them, some one has to make a header without a adapter plate for your specific application

 

[just4bob50]

Percy's dead soft aluminum header gaskets. They are super soft and conform easily plus they are reusable. Got mine for aroun 30 bucks. These are the only gaskets where I didnt eventually have leaks.

 

[89Notch]

I'm with not using an adapter, I have hooker headers on my afr 185's with no adapter and they don't leak at all

 

[thehueypilot]

I personally would not put any adaoter plate on a header, theyre usually a pain to make seal with just one gasket, Return them, some one has to make a header without a adapter plate for your specific application

I agree 100% except when you get into the 2" tube size and above most of them require these sub-plates because of the tiny exhaust port surfaces on a Ford head.

 

[Dark Knight]

Is it one long adapter plate, or the the one that goes to each port? If you have a single flange header, you might have to cut it between ports to give it some flexability to pull each tube tight. Might try the wet header gasket trick too... soak them in water for awhile, then put them on and let it run till they dry..

 

[thehueypilot]

It is one long adapter plate. The header flange has one tube that is seperate on the end, but it still leaks. The problem is the countersunk screw heads are slightly below the surface so the gasket cannot seal the difference between the two surfaces. I will take the plate off and grind it so the screw heads are flush with the adapter plate surface (the way Hooker should have done in the first place). Thanks for the input!