K & N stub stack gimmick or ?
 

has anybody tried these and actually had a performance increase at the track? or are they just another gizmo like the turbo fuel atomizer that will net me more mpg in my street cat?

Stub stack actually works well on 2 bbl circle track cars as the choke tower entry is a restriction. You can cut the choke tower off but you still have a non radiused entry. The stub stack has a large radiused entry and improves airflow into the choke tower/venturi area on a 2 bbl.

On a 4 bbl a HP or Proform type mainbody is a better deal.

Tom V.

Ive heard they work but my motor really didnt like it at all.
We tried one on a 482ci w/ 1050Dom during dyno tune and it was so bad it even sounded worse. Really screwed the airflow. Its almost as if Holley engineers knew what they were doing when they designed the ugly top of the carb. LOL

That is why I did not recommend it for the 4 bbl, lol!

Tom V.

i should have mentioned use for carter afb.

a few years ago we were finishing a dyno on my old 455,we just started unhooking the stuff and i said hold on for a sec we put it on the 850 hp holley and it picked up 15hp,i never run with out it

has anyone tried one in a shaker scoop? Or on a quadrajet?

The top of a dominator is a big difference compared to the top of a 4150 carb with the choke airhorn.

I think the stub stack works OK on carbs that still have that choke airhorn intact,but once that is gone/removed,so goes the reason to use a stub stack.

:2cents:

worked on my combo, i use a holley 850 with the choke horn still in tact.

we use it on a 477 BBc with a old style ( pre Hp ) 1150 and it smoothed up the idle ,and lowered the 60 ft by .05 and about a .10 in the 1/4 and 1-2 + in mph its on a 70 1/2 all steel camaro with a working 4 inch cowl sealed to the carb pan , IMO its a good deal ,also it made the motor smooth out at the top end as you could see the needle on the tach flutter before we used it . plugs are more even in color from cylinder to cylinder .best run was 10.35 @132 with it on .

It picked up 10hp on our 850 when we had the car on a chassis dyno. But that carb still had the choke tower.

I ran one with a Proform 850 but was made to run with a K&N velocity stack.Its almost nothing at that point,just a little plastc ring.I found no E.T. differance.I still have it hanging on the wall,maybe I will try it with my HP 1000 next race,couldnt hurt.

Guess nobody except you & me run AFB's Bob...;):D:focus:
Sounds like they get a NO from Tom V........