Holley TBI adapter

[EagleMark]

There are also a couple differant TBI units. one with 2 holes seperated and one that has center open.

Divided.


Open


I beleive the open ones came on Camaro and Caprice. With that in mind and proven results of CFM Tech spacer that has a split opening for divided TBI
http://marine-performance-parts.com/...eanerstud.aspx

We used the divided TBI and made the adapter open while also machining the intake for straight shot passages when we made the TBI adapter at the machine shop for my sons 345 IH motor.

[PJG1173]

what would the advantage be to the open one?

[EagleMark]

Airflow can be used from both sides, balenced. There is a difference in intake manifolds as well between the 2. The IH maifold was also machined/seperated like the adapter to match the intake of open TBI.

But if you don't have your intake off like we did during a rebuild then just use the CFM adapter with open TBI gasket.

[PJG1173]

Hmm I'll have to look at that. i don't think the divider in my plentum comes all the way up to the top of the flange. the adapter under my tbi adapter is open, so I guess I am already good there. I can't find a good enough pic of the holley adapter to see if it is divided all the way down or not.