Intake Gasket Question
Thread Starter
Melting Slicks
Joined: Apr 1999
Posts: 2,010
Likes: 3
From: Moon Twp. PA USA
Intake Gasket Question
I've been using FelPro 1205 intake gaskets (0.060 thick) because they match my ports. New engine is zero decked which means, in my case, about 0.030 less deck material. Bolting the TF aluminum heads on, is a 0.060 gasket going to seal? All of the 0.120 thick gaskets I have seen have way larger port sizes.
Any suggestions?
Thanks,
Any suggestions?
Thanks,
Racer
Joined: Apr 2004
Posts: 401
Likes: 0
From: IL
TF lists a 1205 (.060" w/1.28x2.09") and a 1266 (.125" w/1.31"x2.21") can be used with their 23° cyl heads. A 1206 (.060") has the same port size as the 1266. Usually when the heads/block have been machined the intake will also need to be machined. But not the same amount, there's a ratio or percent to be machined. I just can't find the info right now. You should be able to set the intake in place, with the side rails in place, but without the end seals and check to see how the intake bolt holes line up. You maybe able to make up the difference with the thicker gasket to "line up" the holes. Use oil rated RTV instead of the cork end strips. If the alignment is off then you'll have to mill the side rails the correct amount to install the intake.
There is a guage we sell 2520/2521 to measure the interference angle but this is typically only for the guys angle milling heads.
I checking on the ratios now, should have something in a few minutes. Side rails are one ratio, while the end rails are another.
Later.
There is a guage we sell 2520/2521 to measure the interference angle but this is typically only for the guys angle milling heads.
I checking on the ratios now, should have something in a few minutes. Side rails are one ratio, while the end rails are another.
Later.
Racer
Joined: Apr 2004
Posts: 401
Likes: 0
From: IL
Found it!
Small Block Chevy;
Intake side rails 1.2 x .010" (amount milled) =.012"
Top of Block 1.7 x .010" (amount milled) =.017"
In your case change .010" to .030" to the above calc and you'll get the amount to mill. You maybe able to make it all up in just the intake (side rails and frt/rear end rails) and not the heads. Intakes are cheaper than heads, in case these heads will ever be swapped to another block. Machineshop should know about this already.
With the heads on (and head gaskets), use the 1205 for the inspection and go from there. You'll see what I'm trying to discribe.
Later.
Small Block Chevy;
Intake side rails 1.2 x .010" (amount milled) =.012"
Top of Block 1.7 x .010" (amount milled) =.017"
In your case change .010" to .030" to the above calc and you'll get the amount to mill. You maybe able to make it all up in just the intake (side rails and frt/rear end rails) and not the heads. Intakes are cheaper than heads, in case these heads will ever be swapped to another block. Machineshop should know about this already.
With the heads on (and head gaskets), use the 1205 for the inspection and go from there. You'll see what I'm trying to discribe.
Later.
