I have a Spread bore, manual secondaries Holley.Could just be an old truck carb I dont know :confused: The numbers on the choke flange are LIST-6210-3
1490
----------------- TROY

MAYBE ITS A RARE GEM :D :D

Your carb is a Holley quadrajet replacement carb. these can work well but differ from the regular 4150 and 4160 Holley carbs in a lot of areas. Some of these have reverse idle mixture screws-clockwise to richen counter clockwise to lean. Also they use different metering blocks and some models have a secondary power valve. They do tend to run rich on mild engines but can be tuned to work well. Evidently somebody scrapped your original quadrajunk and bolted this on. Do a seach on spreadbore and I'm sure you'll find more info here. graemlins/thumbsup.gif

THANKS ! BaddBob graemlins/thumbsup.gif I Had the carb laying around, I will do a search to learn more, I will need to locate some choke parts, the butterfly & rod are there, but the rest is missing :rolleyes: will Holley refurbish old carbs ?
TROY

http://www.holley.com/HiOctn/ProdLine/CarbList.pdf
http://www.holley.com/HiOctn/ProdLine/Products/FMS/FMSCA/FMSCA.html

That's a good carb for a street 350. It's a divorced choke type, so the thermostat is mounted on the intake rather than on the side of the carb.

Those carbs are extremely easy to rebuild. There's no need to send it off to Holley, as anybody that has any mechanical aptitude at all can manage one of those. You can get kits at your local speed shop, places like Summit & Jeg's, even some regular parts stores will have it.

It's hard to describe what's supposed to be there; the instructions in the kit will give you an idea what it is.

They do work well on mild motors but the only problem is they are a DBL pump. The -3 should have a reverse idle circuit which actually is easier to adjust if you have a very mild cam. Just get a kit and and follow the instructions. They are a rather simple design.

Originally posted by Her Malibu:
I have a Spread bore, manual secondaries Holley.Could just be an old truck carb I dont know :confused: The numbers on the choke flange are LIST-6210-3
1490
----------------- TROY

MAYBE ITS A RARE GEM :D :D Those are good carbs! Its not just an old Truck carb, as others have said, it is a "hi performance" replacement for the QuadraJET. ALl the jets, powervalves, pump cams, all work with that carb- you can get shooters for it too- the "anti pullover" type.. The only bad thing is the fact that the rebuild kits are kinda pricey because the gaskets are different than the "common" Holleys.

Just make sure you get teh floats right the first time. Check it once- then twice, then three times to be sure! They arent externally adjustable on the dbl pumper, from what I remember.

As for Choke-- LOL! Forget the choke. Put that sucker on, give it two pumps, and Ill bet it'll start right up. Otherwise, just reuse the choke stuff on the intake, or get a kit. If its a Holley, a choke is optional tongue.gif ...