670cfm on stock 350.

[derrick79]

I know I posted a thread a while back asking what people suggested for a good carb to put on my STOCK 350 but since my truck is 4x4 and I use it as a 4x4 I was looking at the holley truck avenger carb. Would the 670 cfm be too big for my 350? I read on a few other site that guys have had to change the jets, new power valves, accel pump discharge nozzles and the accel pump cam kit to get this carb to run good. This is my first carbed truck so I am still really new to tuning and that just sounds like a major headache. A buddy has one on his bronco with a 400 and he loves it. But its also a balanced and blue printed 400 compared to my stock 350. Anyway I am just looking for a little guidance here. If not the truck avenger, anyone suggest a good off-road type carb?

[txchainsawgogi]

run a rebuilt stocker quadrajet.

[bowtieman82]

you shouldn't had to change any thing but the jets. once you get the right jets it should run just fine, all the other stuff will work just fine, as long as you don't adjust them. just the idle and mixture screws. if it has vacum secondary you can change the spring to get better fuel miles. if you need help just ask, i love Holley carb.

[1980c10]

I dynoed the 670 street avenger on my 350 with a mild cam, edelbrock performer intake, 1" open spacer, vortech heads and 9.7 to 1 comp. ratio.
-had to increase the jet sizes a couple of times with the 670.
I also run with a 770 out of the box with the same results without increasing or decreasing jets.

I think you'll probably be able to run the 670 out of the box or with a size or two smaller jets.

As far as the springs for the secondary, you get 3 with the carb; you can change them to determine how soon the secondaries open.