TBITrucker

OK, I bought a Trans dapt TBI adapter plate to mount my TBI on a 4BBl Edelbrock performer manifold.

The Adapter has one oval hole for the injectors to share instead of two seperate round holes.

So when I mount the TBI to it do I use a normal base gasket or do I have to cut out the center section of the gasket to make it match the shape of the plate?

Also what are the little passages on the bottom of the TBI for? With no gasket sealing them and the base being open will this affect anything?

TBITrucker

Anyone? I can realy use some info on this one.

7Point4

I wouldnt think that leaving or cutting out the center section would matter one way or the other, but with nothing to support it, i would cut out the center.

Some of the passages on the bottom, if i remember correctly, are an entry path for the idle air to enter, also some are vacumn routes, to the various vac ports.

I have a homemade adapter on my setup, and just used a regular TBI base gasket to seal it. Dual holes though.

Casey Butt

I used a gasket with the center removed on my TBI. In fact, it came from the manufacturer like that. I can't remember where I got that gasket though ...I think it was either CFM-Tech or Trans-Dapt.

Lots of people run TBI on single-plane manifolds with non-divided plenums ...in those cases everything's wide open underneath the TBI anyway, so those passages beneath the TBI shouldn't create any problems if you remove the center section of the gasket. On a divided-plenum manifold those passages open both sides of the manifold to each other. With a single-hole style spacer you're doing that automatically, so you can cut the center section out of the gasket. It serves no purpose when the area beneath it is open anyway because there's nothing for it to seal.

TBITrucker

Thanks

I was not sure if it would run OK with those passages un sealed on the bottom like that. If it will work then I'll just cut out that center csection and run with it.