Hey guys, haven't been on here in a long time. I've been at school and haven't messed with our corvette much. We finally got the crate motor in and here's what we got so far. 76 corvette. 355 crate motor from jegs http://www.jegs.com/p/Blueprint+Engines/761054/10002/-1 theres the link to it. its a 400 auto with a 2200 stall and for right now stock 3.05 (i think) gears. eventually it will have 3.73's in it. its got headers and a medium( i geuss) rise intake. It makes strong power and tq from 2000-6000 rpm's. I have been looking at carburetors and am still unsure which would be the best. It will be not a daily driver but probably driven 5 days a week at least so it needs to be a streetable carb. heres what i was looking at .... also do you think 750 is too much for this motor?
a ProForm 750 Street carb
http://www.jegs.com/p/Proform/764248/10002/-1
a Holley Street Avenger 670
http://www.jegs.com/i/Holley/510/0-80670/10002/-1
or a Barry grant speed demon 750
http://www.jegs.com/i/Barry+Grant/13...VC385/10002/-1

also if you have any other suggestion for around $400 excluding a quadrajet based carb( edelbrock, jet, etc.) that would be great.

 

well idk about the carbs but i can say i have an almost stock 350 and it will take a 750 with no prob

 

i vote for the holley 670, since it was dynoed with a edlebrock 600, i would think the 670 would do fine.

 

bigger isnt better when it comes to carbs.
the holley website says that for a mildy modified 350 a 600-a 770 will .t the lower cfms will provide more low end torque while the high cfm carbs will be less low end but give more high rpm performance. so you have to decide where your car is going to spend the most time. low to midrange rpms maybe a 670 would be best.
if you are going to spend all your time at redline then get a 770

 

its going to be almost a daily driver so it will hardly ever see a race track and will not spend a ton of time at the redline so you are probably right with the 670. its got a 700 or 770 double pumper that we had laying around and it runs decent but this summer i am gonna invest in a new carb. Would anyone recommend the 650 BG or the 650 proform over the holley?

 

Honestly, the quadrajet, when properly set up and tuned, is an excellent carb. Have you considered rebuilding the one you have and using that?

 

I have the Holley Street Avenger 670.....highly recommend it.

 

i put the quickfuel 680 on my 454. the off the line response is incredible and even all the way to redline it pulls hard. all it needed was a few jet sizes up and it was good to go.

and of course someone had to bring up using the quadrajet, why would he take the square bore intake off of the crate engine he is looking to buy and put on a spreadbore.

 

1. He's going to be driving around town.

2. It's a Corvette not a Corolla so performance is important.

3. Only a Quadrajet can be tuned for optimal around town efficiency and WOT performance at the same time.

4. You can pick up a new Edelbrock Performer intake for just over $100, used people almost give them away.

God bless, Sensei

 

This is absurd and simply not true.
ethanm has narrowed it down to some good choices and the q-jet is not one of them, but as always, some ignoramus has to play the q-jet card. All of the carbs he's looking at will work great for his application. Personally, I've used the Street Avenger and the q-jet and I'll take the Holley. No fuss - just bolt it on and go, and you can buy parts for it just about anywhere, anytime.

 

Because it is cheaper to buy a $150 intake (and you can sell the old one) then to buy a $400 carb. A properly setup q-jet is a good carb. Plus it sounds like he's going to be spending more time on the street, and quadrajets are good for that. But the OP can do whatever he wants, it's his money.

 

Go with a Qjet

 

the motor is already in the car and it is vortec heads so there is no cheap aluminum intake and i really dont want to run a quadrajet cuz i think they look like **** and i just dont want one. haha

 

The q-jet is an ok carb. I just do not understand why some people can't just answer the question that is posted. ethanm asked about 3 different carbs. I gave him a little slice of my real life experience - and now here's more: I have used and still use the quadrajet, but frankly it is a pain in the ***. It was produced for 25 years or so, but also hasn't been made for 25 years or so. Yes - there are millions of them out there, but there are millions of Holleys out there too. The Street Avenger offers a little more modern design. The quick change secondary spring cover makes it just as quick to adjust as swapping the secondary rods or adjusting the air spring on a q-jet. It also has 4 vacuum ports so you you can run your PCV and brake booster off of seperate ports. It is assembled with the blue gaskets which you can usually re-use many times and it comes with enough hardware to hook up to almost any linkage AND the calibration is set pretty close right out of the box for most stock or mild perf 350s. I used a 770 SA on my '77 Firebird and it ran identical 1/4 mile times as it did with a q-jet. MPG was better around town with q-jet but on freeway trips the difference was minute. One of the things I like about the modern Holley type carbs is that I can get parts for them at just about any auto parts store, so if I need or want a set of jets or just a bowl gasket I can go to AutoZone on Sunday and get them. By the time you purchase the new intake, find a good q-jet or buildable core and build it you will be close to the cost of a new carb and you still have to dink with it to make it run good - and now you have to sell your used but new manifold. Not worth it to me, dollar wise or time wise.

 

You don't want a Q-jet, no problem, we're just trying be helpful.

As for my statement, "Only a Quadrajet can be tuned for optimal around town efficiency and WOT performance at the same time."

Lars:
"On a Q-Jet, we see that we can control the fuel mixture throughout the operating range. This is different from a Holley..."


As for that Holley Street Avenger with Vacuum secondaries:

Lars:
"I have done quite a bit of testing, including dyno testing, of mechanical sec and vacuum sec carbs. What I have found is that vacuum secondary carbs will never get the secondaries wide open, even with the lightest springs installed. This impedes performance and results in the carb not delivering its full cfm potential.

...I am now of the opinion that the mechanical secondary carb is the way to go for overal best performance and tuneability. Use the vacuum secondary if you're running a motor home, 4WD, truck for trailer pulling."

You want to go ahead and call Lars an ignoramus too while you are at it?

P.S ethanm, you might just want to ask yourself why so many "ignoramus' " say, "go with the q-jet".

 

I understand that the q-jet can be a great all around carburetor and i really appreciate the advice, but i just really don't want the hassle of having to replace the intake and dist. and vaccuum ports and buy another intake which will be at least $200 plus rebuilding and having someone tune the carb. i just want to buy a holley or one of those others and put it on and drive

 

Nice thing about the 4150 double pump carbs you can now get them with all the adjustments only the dominator carbs came with 40 yrs ago, you can even get the 4500s annular booster's.

The bad part to get into all that adjustment and boosters the cost is in the $550.00 up range.

If I were going to buy a carb even for a mild performance street engine it would be one of the annular boosted holley, demon or quick fuel carbs.

QFT-SS-650-AN
QFT-SS-750-AN
www.summitracing.com

I would go with a 750 AN (annular booster) If I were spending the money.

 

Winner 2008 engine master's Jon Kaase 400 ford 4.00 stroke 4.02 bore (rules best overall TQ & HP starting at 2500 ending at 6500 rpm, allowed compression 10.5, must have flat tappit cam, 91 octain fuel)

He used a single plane manifold holley 1150 HP dominator.

At 2500 rpm engine made 515 ft lbs of torque 618 ft lbs at 5100 rpm,
656 hp at 6100 rpm.

This kind of blows to bits you must have a 600/650 cfm carb to make any down low torque with your 350 chevrolet.

 

I agree with little mouse, if i had it to do over again i"d spend the extra 100 bucks an get one of these. You get quiet a bit for the extra money, an it"s not just another off the shelf carb. Pre run an set up for your engine http://www.aedperformance.com/HO.htm

 

a1senseless - you're kidding - right? Usually I would not even respond to your BS because it get's away from the original post, but in this case I will. I gave my real world experience as does Lars. All you post is some regurgitated respones from someone else. Let's hear what you have really done! Like I said, I use the q-jet, but what I do not understand is why you keep pushing the q-jet when he clearly stated (twice now) that he does not want to use one. As for Lars and his testing - his results reflect his test - what were the specifics? Motor size, cam, heads, intake, exhaust - they all are factors in selecting the best carb. If you must pull quotes out of context, Lars has also posted that mechanical secondary carbs are not necessarry for most street applications.