I need a carb suggestion
Thread Starter
Heel & Toe
Joined: Aug 2005
Posts: 22
Likes: 0
From: Macon MO
I need a carb suggestion
My 69 427/390 needs carb help. This car has been sitting for 7 years and the carb is needing help. I need suggestions on what replacement carb would be a good choice. The 390 horse 427 is completely stock. The car is a 4 speed. The quadrajet that is on the car is #170802120824 cpw, so I don't believe it is the correct carb. I see a Holley 4175 in Summit that is a Quadrajet replacement in 650 CFM. I wonder what the CFM was on the stock carb? Please give me some suggestions.
Le Mans Master
Joined: Jan 2006
Posts: 8,319
Likes: 7
From: Wilmington DE, Drive it like you stole it, 68 327 4 speed coupe
how do you drive
This very much depends on how you like to drive your car. are you a highway cruise of a street light bruiser 
The q jet is a fine carburator and delivers plenty of punch, The edelbrock performer series makes a replacement Q jet (spread bore) unit that works superbly have used it in several applications. The 750 cfm should be fine, and you like the milage as well as the feeling of those absolutley huge secondaries when they open.
They also make a square bore unit though ive never used it my self.
On the other hand if you like the light to light action, or take your runs a 1/4 mile at a time the sqaure bore carb holley double pumper will ensure gobs of fuel spewed down the intake at WOT. in this case around 750 cfm again will be fine.
Take your pick
Feel the power
Tim
The q jet is a fine carburator and delivers plenty of punch, The edelbrock performer series makes a replacement Q jet (spread bore) unit that works superbly have used it in several applications. The 750 cfm should be fine, and you like the milage as well as the feeling of those absolutley huge secondaries when they open.
They also make a square bore unit though ive never used it my self.
On the other hand if you like the light to light action, or take your runs a 1/4 mile at a time the sqaure bore carb holley double pumper will ensure gobs of fuel spewed down the intake at WOT. in this case around 750 cfm again will be fine.
Take your pick
Feel the power
Tim
Last edited by sweethence; Jan 10, 2006 at 11:07 AM.
Thread Starter
Heel & Toe
Joined: Aug 2005
Posts: 22
Likes: 0
From: Macon MO
I think the car will be cruised locally with some 1/4 mile action or stop light to stop light fun. I want the car to run as strong as possible whlie still being a friendly driver. Fuel economy is not an issue. What model Holley would be best?
Le Mans Master
Joined: Jan 2006
Posts: 8,319
Likes: 7
From: Wilmington DE, Drive it like you stole it, 68 327 4 speed coupe
Holley
Holey makes a street avenger product in both the 670 and 770 cfm flow range which one you should choose depends on teh heads and cam in your vette. its pricey, but it a reliable product for the street, and reletivy easy to maintain and modify (jets) once you know how.
The otehr option is to hit ebay, or the catalogs or clasiified, and pick up a used one specific to your engine and rebuild it yourself. Lots of fun and cheeper too. if you have the skills and the patience i would do the rebuild. Though i would still get one that flows at least 700 cfm
if you want out of the box fun, get out your wallet and call up holley
The otehr option is to hit ebay, or the catalogs or clasiified, and pick up a used one specific to your engine and rebuild it yourself. Lots of fun and cheeper too. if you have the skills and the patience i would do the rebuild. Though i would still get one that flows at least 700 cfm
if you want out of the box fun, get out your wallet and call up holley
Drifting
Joined: Nov 2002
Posts: 1,665
Likes: 1
From: Ontario
You could buy a new carb *ahem cough boring*
OR just think about how much fun it would be to rebuild your old carb.
Check out www.corvettefaq.com under intake & tuning for carb info
OR just think about how much fun it would be to rebuild your old carb.
Check out www.corvettefaq.com under intake & tuning for carb info
Safety Car
Joined: Dec 2004
Posts: 4,071
Likes: 0
From: San Diego CA
That the original carburetor? Doing some checks around and some of the 427s came with q-jets and some with a holley 2 barrel, according to the data sheets I'm reading. I'm going to assume it wasn't originally a tri-power.
Anyways, my suggestion is always the q-jet just because it's such a reliable carburetor.
Anyways, my suggestion is always the q-jet just because it's such a reliable carburetor.
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Safety Car
Joined: Dec 2004
Posts: 4,876
Likes: 1
From: Jersey Shore Exit 98
Originally Posted by mikea
I think the car will be cruised locally with some 1/4 mile action or stop light to stop light fun. I want the car to run as strong as possible whlie still being a friendly driver. Fuel economy is not an issue. What model Holley would be best?
Emerging Vendor
Joined: Mar 1999
Posts: 1,599
Likes: 114
From: San Diego CA
A good carb rebuilder can jet/rod this qjet or a period correct one to get great performance from its 750 cfm. Small primaries are great for normal driving and the vacuum secondaries are adjustable too! You can retain your stock fuel line then where with the other choices you'll have to change that too. I don't recommend the Hollley Q-jet replacement as it is only 650 cfm.
A carb change won't get you much horsepower unless the one now is set up poorly---and it will be if the carb on your car now wasn't recalibrated. Other traditional hot-rod mods will have more benefit.
Greg
A carb change won't get you much horsepower unless the one now is set up poorly---and it will be if the carb on your car now wasn't recalibrated. Other traditional hot-rod mods will have more benefit.
Greg
Last edited by corvgreg; Jan 10, 2006 at 05:35 PM.
Drifting
Joined: Sep 2004
Posts: 1,959
Likes: 1
From: North Bend Ohio
I've heard some good things about the Jet stage 2 carburetors.
http://www.jegs.com/webapp/wcs/store...0271&langId=-1
BigBlockk
Later.....
http://www.jegs.com/webapp/wcs/store...0271&langId=-1
BigBlockk
Later.....
