I've begun porting my FIRST intake for my 383 build. I will be gasket matching the base to a FelPro 1205 and opening up the base and runners such that the passage tapers from the inlet at the plenum to the minimum area at the intake manifold exit.

The engine will be going into a 1989 Corvette. Engine details are:

4 bolt truck block
Approx. 10.8 SCR, 8.1 DCR
Callies dragonslayer crank
Manley H-lite rods (6.00")
Mahle pistons
Bret Bauer Cam (230/242 @ .050; 111.5 LSA installed at 110, 0.603/0.577 lift)
AFR 195 Eliminator street heads, owner ported
FIRST intake
1 3/4" headers into full 3" dual exhaust w/ cats
The car has a M6 with 3.33 gears, approx. 3300 lbs.

Here are some pictures of the intake parts before porting and my initial (very) rough-in of the first runner. As the pictures show, I've got a fair amount of material to remove, but these things have plenty of meat for porting. To give an idea of the size, the wooden ***** shown in the porting pictures are 1.75" in diameter. A stock TPI base and runners have a diameter of 1.47". The goal is to get the runners sized to pass a 1.875" ball through the runner all the way into the manifold where the shape transitions to a rectangle. I'm at about 1.86" now -- I'm sneaking up on it so I don't break through.

I'll post more progress pics as I go. Enjoy. :cheers:

 

sounds like a nice buildup

 

Lots of potential with the First intake system. These things are capable of some serious air flow.

 

Nice pics. I'd like to see it when its finished.