82transam

iTrader: (18)

This is kind of a hypothetical at this point since i'm still deciding which direction to go, but lets say I have a 12a that needs to be rebuilt (I do) and I also had the center iron from a GSL SE (again, I do) and wanted to use the SE iron on the 12a to give me the fuel injector holes, how much (if any) porting would i need to do to better match the SE center iron to the 12a front/rear irons? My thought with this project would be to initially run/break in the engine on a carb, and later fuel inject it. If I were to leave the SE iron alone would it run worth a damn on the carb?

Basically i don't have a 12a center iron in front of me to compare, I'm just wondering what everyone's opinion is. I did some searching, but since "SE" is too short of a search term on here I didn't come up with much. Google was a bit more help in that it brought up some threads about it, but there didn't seem to be a consensus on what to do

Any input is welcome

-Sean

BASTARD

iTrader: (4)

you dont have to match primary ports to secondary ports... stock primary ports are much smaller compared to the secondary ports from the factory

dont think of port matching as an issue between primary ports vs. secondary ports, they dont have to match...

think of it as matching primary port for front rotor vs primary port for rear rotor...

and secondary port front rotor vs secondary port rear rotor.

a bigger concern would be, does your intake manifold fit your hypothetical setup???

peejay

The ports are small and there is not much you can do about it before hitting water.

The ports are also in the same spot and size as a Racing Beat 4-port Holley manifold. This is the combo I am using on my 4-port 13B with great success.

I have a strong, sneaking suspicion that the GSL-SE primary port location would line up exactly with the Nikki manifold's primary ports, in both location and dimension.

Ignore 12A center housings, they have huuuuge tall intake ports, and there's no way to port a GSL-SE part out to that size because of how the iron is cast. Plus the injectors would then mount to open air. And there is no good reason to have the runner that large unless you have an intake manifold that is not only large enough but can also effectively direct the air to it, meaning something that does not have a 90 degree turn right before the engine.

ArmyOfOne

iTrader: (12)

I agree with PeeJay on the port size, you have to be very careful on how you port it.

82transam

iTrader: (18)

Great info here guys, thanks!

I'll have to test fit a nikki manifold to it to see how the ports line up. If they do then I'll go ahead with this build and give it a shot.

peejay

Do it to it!

Two notes on putting EFI with Holley manifold. With the GSL-SE fuel rail, there would have been no way to use the pulsation damper. Fortunately I had a rail that I'd tapped the end to NPT and just had an elbow on it. I did have to do some clearancing on the manifold's carb flange, I think to clear the fuel pressure regulator.

Double check everything when you're mocking up, is what I'm getting at. For some reason the carburetor manifolds aren't engineered to clear fuel rails