opening the intake manifold

[addictionMS]

I have been putting together a 3.0 and opened my intake ports size up the the factory 39mm of the earlier cars (yes I have read all the porting debates here, but that is not the question) and my intake manifold is not opened up to 39mm. I am thinking that I should match the intake manifold to the port size, and wondered if anyone had any experience with technique.

for the ports I just used a die grinder and a round file attachment, I expect I could repeat the process, but it was long a painful. I have read about pulnge cutting the heads, intakes appear more tricky, they are not at 90degrees and curved.

Additional question, any ideas on how far into the intake I should remove material to port match, I am thinking about an inch.

Jim

[TimT]

I did the same thing to a set of intakes for one of my engines. I just took a set of dividers, and opened them to the dimension I wanted (39 mm in your case) Then reached in from the top of the manifold and scribed a line in the intakes, and went at it with a die grinder.

The intakes are easy as they are magnesium. ( unless you have some aftermarket ones). The intakes are cinch compared to the heads

[addictionMS]

thanks, these are after market PMO high rise ones.

Jim

[914timo]

I have done the same thing once. It helps a lot if you have a ball with the diameter of 39 or 38mm. You can use the ball testing the port is round and not too big or small.