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Old 08-28-2012, 01:41 PM
1st_chevelle 1st_chevelle is offline
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Default Carb and intake for cowl hood

Well there comes a time in one's life when he needs a new carb and intake. That time is now. Or even sooner if I can find some tnt and send that damn rochester carb to the moon. I got a 468BB stuck with one of those and it's killing my performance. It feels like it's barely making 150HP when I know it's capable of at least 400HP and more. Anybody have a good combo that works with a cowl hood or at least point me in the right direction? Thanks for your time and consideration.
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Old 08-29-2012, 08:07 PM
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Not knowing more details on the motor you probably will need at least a 700 to 750 cfm carb. It depends how your motor is built. I'm no expert in this area so I hope someone else will chim in for you. What cam are you running, compression, etc?
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Last edited by shadowgray396; 08-30-2012 at 10:17 PM. Reason: down size carb size
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Old 08-30-2012, 10:15 AM
1st_chevelle 1st_chevelle is offline
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I'll have to get a hold of the motor guy but it's a stock reground cam and compression is 10:1. A really great shot (Greer Performance) recommended that a 750 should suit it just fine. Don't need a double pumper or anything just a 750 and intake manifold that works with it.
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Old 08-30-2012, 01:42 PM
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A 750 tuned right will suit the needs of 98% of all applications. Many of my friends with big inch LS-based engines run a 750. A few have tried bigger carbs - with lackluster results. One of the slower cars runs mid 10's on drag radials, through the mufflers.

I would think an Edelbrock performer RPM, Weiand Stealth, or something of the like will feed your engine plenty of air.
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Old 08-30-2012, 04:31 PM
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Agree, a 750 or 770 (Holley's new carbs are 770's) would be good unless it's a very high reving 468 and used for mostly racing. Check the Holley and Edlebrock websites. They'll tell you what size carb based on the basics of the engine and how it's used, street, street/strip or strip only.
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Old 08-31-2012, 01:43 PM
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Quote:
Originally Posted by 1st_chevelle View Post
Or even sooner if I can find some tnt and send that damn rochester carb to the moon.
Hate to say it, but I would find someone to rebuild that Q-Jet properly. It's already an 800cfm. When they are set up correctly, they will run with any Holley or Edelbrock out there. I know a lot of people are going to scream and yell about how crappy they are and how great Holley's are, but if they really were crappy, they wouldn't have used them on a billion cars, even ones making 400-450 horsepower. I have had many performance cars running way over 400 horsepower using a Rochester. They run smooth and make great power, just as much as any Holley, when set up right. Problem is that most people dont understand how they work so they call them junk. Which is the furthest thing from the truth. The other carbs are all good, Holleys and Eddys are great, even a little easier to tune for most people. But remember this, NOTHING runs perfectly right out of the box, no matter what they say. The floats are almost NEVER preset from the factory. If you don't set the floats then it will never run the way it is supposed to.
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Old 08-31-2012, 02:27 PM
carpoor carpoor is offline
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I am having Cliff Ruggles redo my factory Quadrajet. I prefer them to the other stuff out there, but to each is own.
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Old 08-31-2012, 03:22 PM
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I have 2 Holleys, 2 Edelbrocks and a Quadrajet running on 5 different cars. They all run great. The Q-jet car can whip the crap out of 3 of the others.
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Old 09-01-2012, 10:45 AM
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My Q jet runs great for me once I got it rejetted
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Old 09-01-2012, 01:02 PM
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I know I have a Holly 750 hanging around, that was what I had prior to the EFI. I really liked it. I think it is all personal preference, and a lot of research to find what will work best. And if your mechanic is someone you trust, then follow his advice.

But I will tell you, the guys on here have had "Driving" experience with the different carbs, and sometimes that means more to me than what a mechanic thinks.
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