[5-7heaven]

Hey!

installing a 6-71 supercharger, on a BBC 454 engine. intending to use two edelbrock 600 or 750 carbs.

with the WEIAND inline carb linkage, both carbs open simultaneously...not what i expected.

is it possible to run progressive linkage for 2-4 barrel carbs, on a supercharged engine? the linkage WILL fit, but would it damage the engine? does the engine NEED to be fed by both carbs, at all times?

FYI, here's my specs:

BBC 454;
8:1cr
peanut-port heads;
stock 2.04-1.72 valves;
mild RV"mystery" cam;
1.75" full-length headers;
carter 120gph mechanical fuel pump;
h-pipe, with full 3" exhaust system;
6-71 WEIAND(new case) supercharger;
8%underdrive;
MSD distributor, curved;
water injection;
might install MSD ignition retard;
92 octane gas, no booster;

TH-350 trans, stock convertor, kickdown disconnected;
3.00 rear gears;
28.75" rear tires;
two carbs, either 600cfm or 750 cfm;
daily driver...a priority;
3800-pound truck;
looking for 12-second runs, with 26"slicks, but not a priority.

progressive carb linkage, or not?

also, which carbs to run? 600 or 750cfm carbs?

FWIW, i'd like this engine to handle like "a bull in a china shop".
thanks.

[roys63]

run the carbs together it will handle it no problem.

[5-7heaven]

okay, but will the engine handle the carbs, with progressive linkage?

and if i run progressive, should i deactivate the idle circuits on the second carb?

BTW, WEIAND recommends either 2-600 carbs...OR 2-750 carbs.

which ones should i use?

[Nico]

regarding the linkage, i have no idea. However regarding the carbs.... I noticed you said it was a daily driver?! The engine will be able to handle 2 750s with that 6-71 on it.... Now that being said, can your gas tank? If you don't give a rat's ash about mileage, which I assume you don't, use the 750s. Using the 600s might give you a little better mileage.


Nico

*I've only had one car with a supercharger on it so I am not a pro with those -- take what I say with a grain of salt :p

[5-7heaven]

actually, i have this notion of wanting good gas mileage, supercharger or not. right now, i can get 17mpg, with 600cfm carb on the 454. HP/TQ is noticeably down, but i had to prove to myself, that it could be done.(i normally use one 750 carb, for excellent throttle response.)

with the supercharger, i have two 750 carbs available. i'll try straight linkage, since i have 'em. then, i'll try the same carbs with progressive linkage.

when i find a second 600 carb, i'll run those with straight linkage, then progressively.(gotta keep the engine running slightly rich, though.)

methinks that my truck will respond well, to two 600 carbs and straight linkage...maybe even 750 carbs with progressive linkage.(i KNOW the big-block wil buck and fuss, with just one 600 carb at idle, like it would right now).

i just wondered if someone's been through this before, and would like to share.

[Kilrcady]

And I was told by the carb guy that You really can't have too much carb on a blower,Too little and she might run lean and thats bad.

[carsavvycook]

Run straight linkage on blowers. Progressive linkage works fine for dual carb manifolds. You don't want to melt her down.