Carburetors Carb discussion and questions. Upgrading your Third Gen's carburetor, swapping TBI to carburetor, or TPI to carburetor? Need LG4 or H.O. info? Post it here.
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Which carb for my 350 sbc.

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Old Nov 2, 2008 | 07:07 AM
  #1  
85camaro350v8's Avatar
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From: Knoxville, TN
Car: 1985 Camaro Sport Coupe
Engine: Twin Turbo crate 350
Transmission: TH350
Axle/Gears: still workin on that
Which carb for my 350 sbc.

Heres the problem I had a v6 85 Camaro and I'm getting ready to put in my new 350.

The guy I bought it from said that the Holley 670 Street Avenger was the way to go, but I heard someone else say that's not big enough for a stall over 1500 rpms. Well I have a 2200 - 2400 stall. Heres everything about the engine and under it I'll tell you the tranny and rear end.
  • 3.484" stroke nodular iron crank
  • 5.7" forged rods with ARP rod bolts
  • 9 to 1 compression flat top pistons
More special features of this engine include:
  • Seasoned 4-bolt main block
  • Deck head gasket surface on block to ensure a good seal
  • New CompCams hydraulic flat tappet high performance cam-NEW INFO-------Lift: .470''-------Duration: 270°
  • 76cc heads with 1.940"Int/1.500"Exh valves
  • New 1.250" high performance springs set up to match cam
  • New High temperature valve seals
  • New Spiral-type valve guides
  • New Screw-in rocker studs with guide plates
  • New Steel rocker arms with ***** and nuts
  • New Hardened push rods
  • New Perfect Circle rings
  • New Double row timing set
  • New High volume oil pump with welded big pickup screen and steel drive shaft and steel guide
  • New Revolutionary 1-pc design molded rubber oil pan gasket with load limiters to prevent over-tightening and higher temperature resistance than standard cork-rubber gaskets
  • New Brass expansion plugs
  • New Edelbrock (non-egr) Dual Plane Performer aluminum intake
  • All parts are painted separately before assembly for that show quality look
  • Edelbrock (non-egr) Dual Plane Performer aluminum intake manifold.
The engine is dynoed (with stock parts [no headers etc.]) at 330 horsepower and 390 ft pounds of torque. I've got nice Edelbrock tubular headers and true dual flowmaster single chambers. Iv'e got a fresh built strong turbo 350 tranny, and a 12 bolt 3.73 geared rear end. Well if your not completey tired from reading all this sorry just please reply your comments. I'm only 16 and this is my first car I learn by all you guys so teach me a little more about carbs.

Last edited by 85camaro350v8; Nov 2, 2008 at 01:54 PM.
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Old Nov 2, 2008 | 08:39 AM
  #2  
irocz436's Avatar
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From: middleville,michigan
Car: 87 irocz
Engine: 436 chevy sbc
Transmission: th 400
Axle/Gears: 373
Re: Which carb for my 350 sbc.

was is the lift on the comp cam that will make a big difference what carb will work best.also what is the duration on cam.
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Old Nov 2, 2008 | 08:59 AM
  #3  
85camaro350v8's Avatar
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From: Knoxville, TN
Car: 1985 Camaro Sport Coupe
Engine: Twin Turbo crate 350
Transmission: TH350
Axle/Gears: still workin on that
Re: Which carb for my 350 sbc.

ill get that info on here as soon as i can i just emailed the shop that built it for a part number
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Old Nov 2, 2008 | 12:23 PM
  #4  
1320_Guy's Avatar
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From: Baton Rouge, LA
Car: 89 RS
Engine: 305
Transmission: th350
Re: Which carb for my 350 sbc.

Are those heads 882s?
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Old Nov 2, 2008 | 01:57 PM
  #5  
85camaro350v8's Avatar
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Joined: Dec 2007
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From: Knoxville, TN
Car: 1985 Camaro Sport Coupe
Engine: Twin Turbo crate 350
Transmission: TH350
Axle/Gears: still workin on that
Re: Which carb for my 350 sbc.

Originally Posted by 1320_Guy
Are those heads 882s?
i have no idea what that means im sorry maybe if you explain i can tell you or get in touch with the shop....sorry
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Old Nov 2, 2008 | 02:35 PM
  #6  
89RsPower!'s Avatar
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Posts: 3,552
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From: New Jersey
Car: 86 Corvette, 89 IROC, 1999 TA
Engine: 350, 350, LS1
Transmission: 700r4, 700r4, T-56
Axle/Gears: 3.07, 373, 4.10
Re: Which carb for my 350 sbc.

882's are the last three digits of the casting number on the heads, 76cc heads are normally what is refered to as smogger junk or wheel chocks. 882 castings are a prime example.
----------
As far as carb recommendation I think you'd be quite happy with a Holley 650 dp, some people may recommend a 750, but in my opinion it's a trade off, a 650 would most likely provide the best throttle responce.

Last edited by 89RsPower!; Nov 2, 2008 at 02:37 PM. Reason: Automerged Doublepost
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Old Nov 2, 2008 | 03:31 PM
  #7  
85camaro350v8's Avatar
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Joined: Dec 2007
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From: Knoxville, TN
Car: 1985 Camaro Sport Coupe
Engine: Twin Turbo crate 350
Transmission: TH350
Axle/Gears: still workin on that
Re: Which carb for my 350 sbc.

Originally Posted by 89RsPower!
882's are the last three digits of the casting number on the heads, 76cc heads are normally what is refered to as smogger junk or wheel chocks. 882 castings are a prime example.
----------
As far as carb recommendation I think you'd be quite happy with a Holley 650 dp, some people may recommend a 750, but in my opinion it's a trade off, a 650 would most likely provide the best throttle responce.

so in other words my heads arent any good
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Old Nov 2, 2008 | 07:11 PM
  #8  
89RsPower!'s Avatar
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Joined: Apr 2002
Posts: 3,552
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From: New Jersey
Car: 86 Corvette, 89 IROC, 1999 TA
Engine: 350, 350, LS1
Transmission: 700r4, 700r4, T-56
Axle/Gears: 3.07, 373, 4.10
Re: Which carb for my 350 sbc.

I was generalizing, find out what the casting number of the heads are and find out what they actually are (casting numbers are located under the valve cover and are typically 7 or 8 digits). Chances are they arn't anything great but that really doesn't matter at this point. Heads are changeable in the future if you ever decide to upgrade. It sounds like a basic rebuilt 350 which is a decent starting point for a reliable street car. Get yourself a carb, get it running and go from there. Also keep in mind the hp and torque ratings are most likely at the flywheel, the actual output at the rear wheels will be a good deal lower when you take into account losses from drivetrain, exhaust, and accessories. 10% to 15% loss is cosidered normal.

Last edited by 89RsPower!; Nov 2, 2008 at 07:16 PM.
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Old Nov 3, 2008 | 09:20 AM
  #9  
85camaro350v8's Avatar
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Joined: Dec 2007
Posts: 87
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From: Knoxville, TN
Car: 1985 Camaro Sport Coupe
Engine: Twin Turbo crate 350
Transmission: TH350
Axle/Gears: still workin on that
Re: Which carb for my 350 sbc.

Originally Posted by 89RsPower!
I was generalizing, find out what the casting number of the heads are and find out what they actually are (casting numbers are located under the valve cover and are typically 7 or 8 digits). Chances are they arn't anything great but that really doesn't matter at this point. Heads are changeable in the future if you ever decide to upgrade. It sounds like a basic rebuilt 350 which is a decent starting point for a reliable street car. Get yourself a carb, get it running and go from there. Also keep in mind the hp and torque ratings are most likely at the flywheel, the actual output at the rear wheels will be a good deal lower when you take into account losses from drivetrain, exhaust, and accessories. 10% to 15% loss is cosidered normal.
thanks alot man i guess its all just a learning process and you've helped a lot
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Old Nov 4, 2008 | 03:04 PM
  #10  
85camaro350v8's Avatar
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Joined: Dec 2007
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From: Knoxville, TN
Car: 1985 Camaro Sport Coupe
Engine: Twin Turbo crate 350
Transmission: TH350
Axle/Gears: still workin on that
Re: Which carb for my 350 sbc.

NEW INFO
----
the heads are 369's
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Old Nov 4, 2008 | 06:28 PM
  #11  
wrsjr's Avatar
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Posts: 282
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From: Birmingham, AL
Car: 1991 Camaro RS
Engine: 355
Transmission: 700R4
Axle/Gears: 10 bolt Richmond 3.73 posi w/ discs
Re: Which carb for my 350 sbc.

A 670 will probably be too big. You'll be better off with a 600 cfm or 650 at max.
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Old Nov 4, 2008 | 11:16 PM
  #12  
five7kid's Avatar
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From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Originally Posted by 85camaro350v8
NEW INFO
----
the heads are 369's
"33417369...90-up...350..........Gen.I Goodwrench crate motor,"Hecho en Mexico", 76cc"

Mexican version of the 882's.
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Old Nov 5, 2008 | 06:36 AM
  #13  
85camaro350v8's Avatar
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Joined: Dec 2007
Posts: 87
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From: Knoxville, TN
Car: 1985 Camaro Sport Coupe
Engine: Twin Turbo crate 350
Transmission: TH350
Axle/Gears: still workin on that
Re: Which carb for my 350 sbc.

Originally Posted by wrsjr
A 670 will probably be too big. You'll be better off with a 600 cfm or 650 at max.
double pumper?
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Old Nov 5, 2008 | 11:14 AM
  #14  
five7kid's Avatar
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From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
A Holley 670 CFM is a Street Avenger vacuum secondary carb. I would not recommend it.

The heads are costing you 20-30 HP vs. what Vortecs would produce. A 670 Street Avenger would be .1 to .2 seconds slower in the quarter mile vs. a 650 double pumper.
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Old Nov 5, 2008 | 01:00 PM
  #15  
wrsjr's Avatar
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From: Birmingham, AL
Car: 1991 Camaro RS
Engine: 355
Transmission: 700R4
Axle/Gears: 10 bolt Richmond 3.73 posi w/ discs
Re: Which carb for my 350 sbc.

Originally Posted by 85camaro350v8
double pumper?
If its a stick, otherwise go with vac secondaries if its an automatic.
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Old Nov 5, 2008 | 01:35 PM
  #16  
five7kid's Avatar
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From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
That's failsafe advice to keep people who think "bigger is always better" from ruining your reputation.

There's nothing wrong with a properly sized double pumper on an automatic car. It took me awhile, but I finally learned that lesson in 2003 - 750 VS to 650 DP gained .2 sec in the quarter. Going to 750 DP gained another tenth.
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Old Nov 5, 2008 | 11:41 PM
  #17  
89RsPower!'s Avatar
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From: New Jersey
Car: 86 Corvette, 89 IROC, 1999 TA
Engine: 350, 350, LS1
Transmission: 700r4, 700r4, T-56
Axle/Gears: 3.07, 373, 4.10
Re: Which carb for my 350 sbc.


Listen to that man, he knows what he's talking about.
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Old Nov 6, 2008 | 09:26 AM
  #18  
85camaro350v8's Avatar
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From: Knoxville, TN
Car: 1985 Camaro Sport Coupe
Engine: Twin Turbo crate 350
Transmission: TH350
Axle/Gears: still workin on that
Re: Which carb for my 350 sbc.

So should I go with the Holley Classic 650 Double Pumper? Im also looking at the Road Demon 725 Dual Line carb. What do you think check out my poll. Why or why not should I use one or the other?

Holley
http://www.jegs.com/p/Holley/746470/10002/-1

Road Demon
http://www.jegs.com/i/Barry+Grant/13...0VE-R/10002/-1
Thanks

Last edited by 85camaro350v8; Nov 6, 2008 at 10:09 AM.
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Old Nov 6, 2008 | 10:22 AM
  #19  
five7kid's Avatar
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From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
The Road Demon is vacuum secondary. Quality problems with Demons seem to be pretty common these days.

The classic DP would be fine. A 750 wouldn't be too big, especially if you get better heads some day.
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Old Nov 6, 2008 | 12:23 PM
  #20  
wrsjr's Avatar
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From: Birmingham, AL
Car: 1991 Camaro RS
Engine: 355
Transmission: 700R4
Axle/Gears: 10 bolt Richmond 3.73 posi w/ discs
Re: Which carb for my 350 sbc.

I just bought a Quick Fuel 650DP, its a great carb. I bought it used (less than a year old).
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Old Nov 6, 2008 | 04:01 PM
  #21  
85camaro350v8's Avatar
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From: Knoxville, TN
Car: 1985 Camaro Sport Coupe
Engine: Twin Turbo crate 350
Transmission: TH350
Axle/Gears: still workin on that
Re: Which carb for my 350 sbc.

Originally Posted by five7kid
The Road Demon is vacuum secondary. Quality problems with Demons seem to be pretty common these days.

The classic DP would be fine. A 750 wouldn't be too big, especially if you get better heads some day.

what about a quickfuel what do you have to say about those?
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Old Nov 6, 2008 | 04:50 PM
  #22  
five7kid's Avatar
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From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
They have great products. I'm running their E85 stuff.
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