Intake to heads match-up ?

[ajboots4]

From reading through some posts it sounds like the 4bbl intake, C2AE94256 (given to me for free) will NOT marry up with my current heads, C8AE-H - different port dimension. Sound right ?

[My427stang]

The early manifold will bolt on and run, and is an improvement over a 2 barrel, but there is port mismatch.

You need to run the intake gasket to match the intake, not the head though. The MS90145 will seal the larger low riser port.

Most of the intake flow follows the roof of the port, so it's not as bad as it would seem. It's not perfect, but if it's free and on a budget, as long as it seals up it will likely outpower a 2 barrel

[ajboots4]

Cool. I'm going to run with it. thx

[My427stang]

Just to be clear for anyone doing this later

You have to use the gasket that matches the larger port, regardless of which way the mismatch is

- Edel RPM (medium riser/small) with Edel RPM ports (medium riser/small), use a Mr Gasket 202A or 1247S3 Felpro
- Edelbrock RPM to D2, C8, (small/small) - use a Mr Gasket 202A or 1247S3 Felpro
- Edel RPM (small) with low riser ports (tall), use MS90145 (tall) or Felpro 1246S3 (Mismatch correct direction but still need tall gasket to seal bottom of port)
- Low riser intake (tall) with C8, D2, or medium riser - use MS90145 (tall) or Felpro 1246S3 (Mismatch WRONG direction but still need tall gasket to seal bottom of port)

The only factory truck head that will not be a "small" port is a C6AE-R common on 352s, it's a low riser port, in that case, it uses the MS90145, always match the taller port