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Carburetor Size

  
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Carburetor Size

 
deemann deemann
User | Posts: 57 | Joined: 02/09
Posted: 12/30/13
09:03 PM

Any recommendations on the size carburetor for the following:

75 Camaro - 3,900 pounds
383 engine
gm iron vortec heads  10.0:1 compression
comp cam .480/.480  224 duration  .500
turbo 350 auto
3.73 gears posi-trac
rear wheel power with an 800cfm carb  282hp/308tq

Looking for a good performance street application that is driveable, but not to be completely humiliated during the nostalgia drag races at the track  

joe- joe-
User | Posts: 133 | Joined: 11/11
Posted: 12/30/13
09:56 PM

i'd think a dual feed, 750 vacuum secondary should work fine.  

what size/stall converter are you running?

chassis dynoing a car can be a humbling experience i'm told. Shocked  but there is a certain amount of driveline loss.  maybe 25% or more?  
joe-

deemann deemann
User | Posts: 57 | Joined: 02/09
Posted: 12/31/13
05:51 AM

Correction on the cam  .480/.480  232 duration  

deemann deemann
User | Posts: 57 | Joined: 02/09
Posted: 12/31/13
05:52 AM

2,000 stall  

Dave632 Dave632
Addict | Posts: 2219 | Joined: 07/08
Posted: 12/31/13
02:44 PM

Yes driveline loss can be humiliating. The bigger the rear, (I am talking about size like a Dana 60), the higher the stall and the heavier duty the tranny, all eat into driveline loss. An example I remember from a magazine showed a 30% loss from flywheel to rear wheels. BB Chevy 700hp at the flywheel got 494 at the rear wheels for approximately a 33% loss.
My BB632 in the 68 Camaro got 606 at the rear wheels and it pushed the heavy car to 144 in the 1/4 on motor. I never had it dyno'd at the flywheel buy my guess would have been around 900. The Beretta was never dyno'd but it went 135 in the 1/8th on motor. That one was probably hitting in the 1000-1100 range at the flywheel.
I would guess your engine is in the 375-400 range at the flywheel. As far as carb size you are not to far off. A 750 might be a little closer to ideal but I don't think it would make any large difference if any. Might help ET with a little better mid range with a slight loss in the upper rpm ranges.
You should not be embarrassed at the track unless you are trying to beat some real strong combination. A friend of mine wanted to race my Beretta with his nitrous street Mustang, he had painted the car and was curious about how he would do against it. The track official in the staging lanes thought it was funny. My friend said he watched the Beretta just disappear into the sunset but he still enjoyed the race.  
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dond1965 dond1965
Enthusiast | Posts: 294 | Joined: 12/13
Posted: 12/31/13
08:51 PM

at the strip, hood scoop, 930 cfm PREDATOR!!  

dond1965 dond1965
Enthusiast | Posts: 294 | Joined: 12/13
Posted: 01/01/14
12:03 PM

Icon Quotejoe-:
i'd think a dual feed, 750 vacuum secondary should work fine.  

what size/stall converter are you running?

chassis dynoing a car can be a humbling experience i'm told. Shocked  but there is a certain amount of driveline loss.  maybe 25% or more?


hola amigo Laugh