[airman_turtle]

im trying to figure out what carb i should go with. i am getting drawn to the Holley Avenger Series. Currently i have a 600cfm holley 4bbl and i know it is two small. Im unsure whether i should get the 670, or 770 avenger. They say the 670 is for 300-400 hp and the 770 is 400-500. Im not sure where i stand. The things that matter are...

Comp Cams - 520 intake lift, 490 exhaust.

2.05 intake valve and 1.60 exhaust

headers and 2 1/2 in dual exhaust

350 bored .040 with 10.5:1 compression

Edelbrock Performer Air Gap (want to get a Performer RPM though)

Auto tranny

 

[killerformula]

670 is plenty

K

 

[airman_turtle]

k thanks

 

[stepside454]

Airman, how much RPM does the motor see ?

 

[airman_turtle]

5800-6000 max

 

[stepside454]

Yep, what Killer said, out of those 2 the 670 is more than plenty

 

[airman_turtle]

ok, what if i wanted to use a demon? i like those as well, but i know they really under-rate them. would i go with a 575 or 650 cfm?

 

[stepside454]

650 would be perfect

 

[Tech @ BG]

650 Vacuum Secondary Speed Demon P/N 1282010VE.

 

[Mighty Mouse S-10]

I'm currently running a 770 Avenger on a similarly built 350. I started out with a 600 edelbrock, but it had no top end.( above 5000 rpm) When I changed to the 770 I lost a little off the bottom but the top end really came to life.( pulled hard to the 6000 rpm rev limit) So now I'm looking for a deal on a 670. I like the Holley carb, but if I can get a deal on a Barry Grant 650 I would definitely give it a run. I'll be curious to know which way you go and how it comes out.

 

[stepside454]

Mighty Im really surprised 600 isnt enough for a 350 to 5000 RPMs, maybe there was a tuning issue. I built a 400 for a buddys truck, its got a 600 Edelbrock on it, it pulls to 5K without a probem. Ive got a 770 on my 454.

 

[Mighty Mouse S-10]

Maybe a Holley would have performed better than the Edelbrock? The cam is 465/488 224/234 with 1.6 roller rockers on ported and polished Bowtie heads with Manley race flows. Headers and Flowmasters, so it breathes pretty good. Like I said the 770 is to big so maybe a 650 or 670. I've been looking at the Barry Grants but they are a little steep for my wallet.