best carb for a 477 big block stroker?

[3rdelke]

my son and I are about ready to fire up his 67 gtx clone, we have a 650 carb to start it up, but if all goes well, we know we will need to feed it a little better. we think its about 12.5 to 1 compression, will have to mix in some race fuel. thanks....Bob

 

[mmissile]

Need a bunch more info........

 

[3rdelke]

my boy knows more about it than I do, hope he will visit site maybe fill in some blanks

 

[Garys1969RR]

I am running an 850 Holley dbl pumper on my 451, and it is working real good. At 13 to 1 C/Ratio, I have to run 50/50 Sunoco 100 with 91 premium. But I am at 5600 feet. You may need a little higher octane since you are prob around a thousand feet above sea level?

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You can also add some E 85 to raise the octane, since it is at 105.

 

[3rdelke]

started with a 413 block, 30 over 426 ross forged pistons(30 over), 4.125 stroker crank. hemi 4 speed, 4.10 dana mini tub

 

[Garys1969RR]

Maybe add 2 gallons to six or eight gallons of 50/50 mix. Keep in mind that E 85 will tend to lean out the mixture as it needs larger jets in the carb if you run it full strength.

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What heads are you using? What cc chambers?

 

[3rdelke]

gary, thx, the initial advise we got was 1150, but I know we don't want to over carb it

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gary, ill find out, seems like they were the biggest heads this side of hemis, forgive my ignorance. mopars are new to me but t
he kid loves em, got to say im pretty excited to fire it, finally got the oil pressure up, waiting for a high performance coil and we wll know if all these thousands are gonna pay off

 

[Garys1969RR]

If its a street car, you will get much better throttle response with a smaller carb. Start with what you have and move up from there.

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I have seen a Cuda running 10s with a 750 CFM carb.

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Are they iron or alum heads?

 

[3rdelke]

it is primarily street, thanks, sounds like sound advise, how much do you think a 650 will hold it back?

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iron heads

 

[Garys1969RR]

It will work great at lower engine speeds, above 4000 RPM is where it may start to fall off. We are running a 650 dbl pumper on my sons 383, and it is running low 12s with nitrous. What cam are you using? What Lift and duration?

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This 383 is turning 5500 RPM thru the lites at 110 MPH, and it likes the 650. But you have almost a hundred more cubic inches. Get all the initial tuning done with the 650, then go to an 850 or more.

 

[3rdelke]

int 285 ex297 dur .050 lift .545 comp hydraulic

 

[Garys1969RR]

Dont you just love these father and son projects? We are currently buying another 69 Roadrunner to work on.

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int 285 ex297 dur .050 lift .545 comp hydraulic

That sounds like total duration, which is similar to what I am running. Mine is 292 duration intake and ex, and .509 lift. A great cam to use. Good choice.

 

[3rdelke]

man, you are so right, no matter how close you are to a boy you need some shared interest. kevin lives and works in china and we tried a blitz build, but eight or ten weeks was a few days short. but it was a blast! cant wait for his next trip so we can blow the doors off something

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gary, funny thing I helped my dad finish up his 41 chevy coupe and 46 fleetline and we were about the same age respectivly

 

[Cranky]

Do you know anyone with a collection of carbs that you can experiment with? You may not like an 850 if it's mainly a street car but an 800 might be the sweet one. The down side to Holley DP's is they are generally gas hogs in town. I ran a 600 DP on a 289 years ago and go terrible mileage in town but it knocked down 21-22 on the road. It was a 4 speed car so it worked pretty well. DP's with automatics are usually not a good match unless you're running some stall but with the right tuning and carb size, they can work good but usually won't give you very good mileage on the highway unless the car is geared pretty high and 4:10's ain't high way gears plus high stall converters don't like road gears very well.

 

[Garys1969RR]

I agree with Cranky, a street car works best with a vac secondary carb. I've always liked the 3310 Holley 780. I ran low 12s with one of those on a 413 in a 65 Belvedere.

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Good luck!

 

[3rdelke]

Do you know anyone with a collection of carbs that you can experiment with? You may not like an 850 if it's mainly a street car but an 800 might be the sweet one. The down side to Holley DP's is they are generally gas hogs in town. I ran a 600 DP on a 289 years ago and go terrible mileage in town but it knocked down 21-22 on the road. It was a 4 speed car so it worked pretty well. DP's with automatics are usually not a good match unless you're running some stall but with the right tuning and carb size, they can work good but usually won't give you very good mileage on the highway unless the car is geared pretty high and 4:10's ain't high way gears plus high stall converters don't like road gears very well.

Cranky, thx for info, I don't. its primarily street, but not intended for every day use, he will drive it when here is back here in the states

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gary, thanks, just checked them out on ebay, very affordable as well , thx, Bob

I agree with Cranky, a street car works best with a vac secondary carb. I've always liked the 3310 Holley 780. I ran low 12s with one of those on a 413 in a 65 Belvedere.

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Good luck!

 

[terzmo]

I ran a 950 on all 3 BB strokers.

 

[3rdelke]

thanks