The V8 Owners Forum -

Yess the vent tubes, and according to your picture they are cut off to. I surely think here lies the origin of your issues.
See the difference....

Holley did design it with a purpose. You can mill of the choke horn but you can't touch the vent tubes.

Left & right have the same total hight and should face outwards.
Has something to do with the airflow, disturbtion and interruption. where the air enters the throat of the carb.

Thanks for that.

I did some reading, and some holley carbs have removable vent tubes?

Ill have another look at mine today, hopefully they are just missing!!!
(if not, bugger!)

Stu

Well I had a rummage and found some ally pipe in the garage that was a nice snug fit in the vent holes!!!
Made them so they stuck about 1 1/4" out the top with slash cut away from the carb throat.


Took it out for about a 10 mile drive.
Plugs 1, 2, 3, 4, 6 and 7 are relatively "clean" with a tan ring around the top of the insulator,
plugs 5+8 are starting to go the same way now (prob should have cleaned the soot off first!)

Looks like mixture distribution problem is now gone, thanks JP!

As for the stumbling/hesitation when applying throttle, I think I need to look at the pump nozzle sizes......?

Stu