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I am going to put a new carb on my 62 Ford Galaxie with a 300 hp 390. I currently have an Edelbrock Comp carb 750 cfm sitting a shelf. My question is what is the difference between the Competition and Performer carbs. Do you think the 750 cfm Comp. carb is a good choice to use on my 390? The engine is original so far, but I will be putting a different cam in shortly.

Any help appreciated.

BobG
 

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unless Im mistaken...the Competion series carbs are Carters, Performers are Edelbrocks....same carb differant name
 

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Carbs

Edelbrock bought out Carter carbs and have made a few upgrades to the carbs, but they are essentially the same carb.
As for carburetion for your 390, that 750 is way more carb than you need for a stock engine, or even if it was mildly modified.
According to my handy calculator, you would have to be able to turn your engine well over 6600 rpm to be able to use all that carb. I would recommend going to a 600 cfm carb, pick up some good bottom end response , and possibly some fuel mileage in the process.

Formula:

Engine CID X desired RPM divided by 3456 = CFM needed at 100% efficiency.

example:

390 X 5500 RPM = 2145000 Divided by 3456= 620 CFM.
Even with a 100% efficient engine ( no such thing), a carburetor will easily feed an engine at up to 15- 20 more rpm than what the formula will emply.
therefore a 620 CFM carb will easily feed your engine up to 6500 RPM.
Remember the guys in NASCAR are running 390 cfm carbs with a restrictor plate under them and are turning over 7000 rpm and making upwards of 600 hp.
Food for thought, A large CFM carb isnt going to help make more hp unless your engine is designed to handle the rpm needed to use it.

One more thing, realistically, your engine very doubtfully sees more than 4000 rpm on the street, so why bother running a big carb.

You MIGHT lose 2-3 hp on top end by going to a smaller carb, but the gains on lower end, due to higher fuel/ air velocities, making for more efficient mixture and combustion will more than offset on lower end and mid range than what you lose on top end.
 

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Max... yep exactly, 600 is a nice size for a stock 390, or any 390 up to about 5000 RPMS. John
 

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stepside454 said:
unless Im mistaken...the Competion series carbs are Carters, Performers are Edelbrocks....same carb differant name
Actually Edelbrock and Carter AFB carbs are both manufactured by Weber. If you look on the top of the carb body you'll see the Weber factory logo. The difference between the two is the metering rods. The Edelbrock carb metering rods are stepped differently than the AFB's. That said, for all intense and purposes they are identical carburetors.

Centerline
 

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comp carbs=high dollars

The resto market is laways looking for the competition rated tagged carter carbs. 409 guys and race Hemi...Thank God for EbAy...


unioncreek said:
I am going to put a new carb on my 62 Ford Galaxie with a 300 hp 390. I currently have an Edelbrock Comp carb 750 cfm sitting a shelf. My question is what is the difference between the Competition and Performer carbs. Do you think the 750 cfm Comp. carb is a good choice to use on my 390? The engine is original so far, but I will be putting a different cam in shortly.

Any help appreciated.

BobG
 

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union,
if you mean a AVS series as a Edelbrock "competition" carb.....

the AVS "Thunder" series has adjustment capability for the secondaries which with your relatively heavy car can be a plus so it won't bog.....(otherwise it is just a Performer)

what is the goal for the car and motor? a weekend cruiser? a full tilt strip car?

because you want the parts rpm's power band to be matched for the carb size, intake and cam (and rear gears)....

(my $.02 so far....yah gotta $$$ carb on the shelf....if you do go ahead and use it....wouldn't be the worst mistake you can make compared to 3/16th's smaller primaries on the 600 cfm carb for cruisin TQ)



sidenote:
Hey Max...been awhile :welcome: .....wish you knew....how many times I have posted: "ALOT more gooder isn't necessarily more gooder".... as a quote from you!
 
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