carb opinion

[89IROC&RS]

Im lookin to buy a early 70's Blazer (yeah not a camaro, but im talkin engines here, which are pretty much the same for the two vehicles) and seeing as its already all mechanical, im starting to look at the idea of running a carb instead of EFI to keep from having to do all the custom wiring and such. Problem is, i dont know jack about carbs except for the extream basics. So im wondering, what do yall suggest as the best balanced carb, in regards to performance, economy (gas mileage), and hassle free operation. Im pretty much leaning towards a Quadrajet, but i dont know how Holley and Edelbrock stack up. Or perhaps some other brand i dont know about. Ive got the camaro, so this isnt really a high hp strip engine, but its more for low RPM high torque for towing and off roading, but ill still be driving it on the street putting some highway miles on it. the base for the engine is a 383cid SBC with Vortec heads, dual plane intake manifold, and a cam with somewhere around .430/.450in lift. im lookin to get a carb with between 600-750cfm. but with the quadrajet i could run an 800cfm without worry cuz of how they operate. im just doin some brainstormin here, and open to ideas and input.

[DaMoNe6969]

Buy a carb, then throw it at someone you dont like..

Then buy yourself a TPI kit and do it the RIGHT WAY!

You said you wanted economy and hassle free operation... And if you know jack about carbs (as I do) than carb is not the way to go..

[89IROC&RS]

lol, yeah i know, and the TPI would give awesome low rpm torque, but i dunno, i dont like not knowing about carbs, so having one on the truck would give me the chance to learn. cuz im sure as shit not putting one on the camaro lol

[1992RS]

Not trying to call you our Iroc, but being the master sbc design guy you are, 383 for low end torque? Anyway, for that size of a motor just to feed it your going to have to get at least a 700cfm carb. I'd get the holley vaccum advance. But that's if you are dead set on getting a carb. Personaly I would go with TBI, it's more off road freindly than the TPI that you covit over. I think the holley commander 950 would be your best option, plus you can get em from 670 up to over 1000cfm. 950 is just the name. And with that there really isn't any costum wiring you have to worry about, cuz it's a stand alone system. well that's my opinion.

[tardster]

Edelbrock is way to damn sensative man, I've got a Edelbrock 650 CFM on my maro and the thing sux bad. You can smell its running way to rich but if you lean it out it wont run, for 150 bucks I can get it set by a shop but hell man I kinda figured it woulda been set from the factory since it only ran me $300 bucks. If your going to go with a carn get you one of those race demon carbs, I've heard there pretty easy to adjust like holly but there kinda pricy

[Pewter'01SS]

This depends on what you want out of it. I originally had a 650 Edelbrock on the S10. It was great as far as not having to keep re-adjusting it. The Edelbrock's are very similar to the Quadrajet in design. Once they are set, you really don't have to mess with them that much. Performance is a whole other issue. (Soooo going to get flamed for this...) For performance, Edlebrock's suck ass. I put a 750 Holley dual feed on my truck and it ran a HELL of a lot better, even though that was really way too much carb for the engine. BUT, they can be tempermental. If you're looking at price, you can get a rebuilt Holley for relativly cheap. The Demon carbs are the same setup as the Holley's but they are improved designs (same with the Edelbrock vs. Quadrajet). Personally, I'll only run a Holley.

[BrakeTorque]

I would buy the 900 Holley, seen and heard nothing but good. And with you running that cam and a 383 then i wouldnt buy anything below a 750cfm.

[1992RS]

oh, hat cam...you know that's a little piss ant cam for that 383 right? your gonna have a starving unhappy engine.

[89IROC&RS]

lol, awww common 92RS, i need ya to work with me here, im not building hp. im building torque. the lift of the cam for a 383 can be very low, and make tons of torque so long as you have enough durration. and yes, 383's are known for their torque not their hp, its the long stroke and long connecting rods, taking advantage of the leverage principle.

i cite the GMPP HT 383, tested by CHP magazine, with 1-5/8in full length headers, very similar cam specs to what i have listed above (factory HT 383 cam), with a dual plane intake and carb, made 341hp@4700 and 447lbs/ft@3100 on 9.1:1 compression, vortec heads, 1.5:1 ratio rockers. and 650cfm carb.

http://www.chevyhiperformance.com/te...841/index.html

dunno if id call that starving boss and on the plus side, with that little cam, i should still be able to get decent cruizing mileage out of it. at least with the right cam. which is also why i was looking at the quadrajet with those tiny little primary bores.

[89IROC&RS]

oh sorry, that was with 1.6:1 ratio rocker arms. my mistake, but still, there is even more room there for improovement without messing with the main parts and have a bulletproof, high torque, good mileage engine just begging for a 4x4 to be wrapped up in

[1992RS]

well next time put the full cam specs on here then.. sheesh. If you have enough duration you'll be alright, but you didn't say that. And still 383's are known for midrange torque more than low end torque, but I guess 3100 is still kinda in the low end. Guess I'm just not used to building a mild engine. Oh speaking of offroad, you should see my buddies 283 he's got in an old CJ7, 400hp 400 and something fpt. It's wicked, he'll spin the motor 8000rpm all day with no problems. I want one.

[89IROC&RS]

lol, yeah i knew you were just in the wrong frame of mind, ill let that one slide without an i told ya so oh and your buddy realizes he has an 8000rpm engine, in a JEEP!!!! *shakes head slowly from side to side*

[1992RS]

I offered him 2 grand for the engine, he didn't want any part of it.

[Hypsi87]

Originally Posted by tardster

Edelbrock is way to damn sensative man, I've got a Edelbrock 650 CFM on my maro and the thing sux bad. You can smell its running way to rich but if you lean it out it wont run, for 150 bucks I can get it set by a shop but hell man I kinda figured it woulda been set from the factory since it only ran me $300 bucks. If your going to go with a carn get you one of those race demon carbs, I've heard there pretty easy to adjust like holly but there kinda pricy

Thats odd, when I was messin with the v-8's back in the day, I always found holly to be the touchy one.

[89IROC&RS]

well, ive heard bad about both edelbrock and holly, anyone got negative feedback on Q-jets?