Holley Help

3b a runnin, what jet size did you change to? I use 51's and carry 49's for higher altitude. Tim mentioned books. two good ones are by Mike Urich and the other by Dave Emanuel.

Holley jets are very close but do not correspond precisely to orifice diameter. Holley says two adjacent jet #'s can have the same orifice diameter but differ in other design elements.

 

The 390 is the hot set-up.................Period.........been running them since the 70's Yes , you will have to make some adjustments from out of the box......but the parts are out there to customize.............it's bore sized correctly for the V6 with vacuum secondaries....off road kits with spring-loaded floats , needle & seat and a new higher cross over vent tube which will eliminate the side hill flooding issue so common in the past are all available.

 

Sounds like you’re making a sudo TA390. Be nice Holley made one to save the trouble.

 

There are things you can do to the street Holleys that make them better on the trail. Raise the bowl vents, vent baffles, spring loaded floats, other stuff. In my experience - without mods, the street Holleys are quite awful on the trail. There are angles where they just will not run, and they flood badly over broken terrain (bumps and jolts). Pretty sure from earlier posts that the 390 comes with side-hung floats, which is what you want for a Jeep carb (not center hung). My understanding is that there were things done to the TA carburetors that cannot be transferred to the 2300/4150/4160 carbs. If you have the two carburetors side-by-side, it would be very interesting to take them both apart and compare the construction.

 

Still has the original jets in it, I think 57's

 

I've actually done this....there's no obvious difference other than the standard off road modifications mentioned above. My understanding is that there's some internal changes in the metering block to enable it to run better at severe angles...I'd love to see a cutaway view that shows what was done.

 

I run a 390 that i made a crossover vent like a TA carb and put a tee fitting and hose to a catch can . fuel will drain out of vent and no flooding playing in the steep and rocky trails. Engine is a kenne bell 231 .