340 carburetor question, need help!

[Moparman01]

As i said in another post, i just picked up a '71 Demon with a 340 in it (slant 6 origionaly). I'm doin a carb and intake swap on it and am wondering which carb to go with. The carb that was on the motor when i got the car was a spread-bore Thermoquad, which i believe is 850cfm, which would have been stock on 71-73 340's. I don't know what year my motor is, and i'm not sure about how it's built other than it has a set of really nice 1.5 Crane roller rockers, and now a Edelbrock Performer intake. I was going to go with a new 600cfm Edelbrock that i have, but i also have an Edelbrock 800 thats been sittin it it's box for years on my shelf, i got the 800 from a freind of mine who pulled it off his 454 camero, so it's still basically set up for a BB chivy. What do you guy's think i should do, go the 600 or step up to the 800?? I don't wanna over carb the thing, and i find it kinda funny i might be running more carb on a 340 than on the mildly built 440 that's in my General Lee (750 Eddy.). Thanks for any help/advise!!

[Challenger340]

IMO, and this is NOT a popular statement,
For both Driving & Performance,
VERY tough to beat the Stock 340 Intake and 850 cfm Thermoquad Carb, when set up "properly", up to about 6000rpm / 230'ish @ .050 Camshafts.

Sry,
I've been there, "where you are", done that, went back to the Thermoquad, and never been sorry I did.

The Edelbrock Performer Intake was an improvement for me, but I still went back to the Thermoquad Carb, and gained Drive-ability, and ET/mph at the track !
Go Figure ?
I just wish they weren't so darn "Ugly" esthetically to the eye.

[Sublime/Sixpack]

  Thermoquad, properly set up!