uberstang1

Well I picked up a great 68 coupe for a steal, i have very limited expereince with carb setups but i do know the offenhouser 360 manifold with two 500 carter 4bbl is just to much fuel, its just not street-able. With that being said I'm going to give the best description of the engine setup and hoping someone can steer me on the right direction for a manifold and single 4 bbl setup which will be great for a street car. The car is powered by a 289, .20 over, keith black pistons. Compression ratio is 9.7:1. Heads are the edlebrock performer RPM aluminums 60cc chambers. Cam is COMP Cams CL31-250-4 - Comp Cams 'Xtreme Energy' Hydraulic Flat Tappet Camshaft Lift: .541''/.544''
Duration: 284°/296°
RPM Range: 2300-6500.

Car has a holly red pump electric fuel pump. Any help would be greatly appreciated. The setup has less that 1k miles on it, owner finished the car several years ago then lost interest.

Dave Severson

My choice would be an Edelbrock Performer RPM Air Gap intake with a 650 Holley carb. If it's a 4 speed car I'd use a mechanical secondary carb, an automatic transmission car I'd use a vacuum secondary. What does it have for ignition? Takes a good spark to keep things running clean.

uberstang1

The car has a built c4 with a 3000 stall convertor. For ignition it has a mallory distributer, msd blaster 2 coil and thats about it.

Dave Severson

Ignition should be adequate for keeping the fires lit, I think you'd be happier with the vacuum secondary 650 carb, easy to tune in the secondary opening with a spring change to make it work right with the trans shifting....

barnett468

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your compression is way too . . it should be 10.5.

eddy rpm or rpm air gap or repo shelby intake.

quick fuel ss680vsf carb . . a 289 shelby with small hesds and small cam had a 715 cfm carb.

if you do not need the kick down on the carb the ss680vs would be the one.

you need to curve the ignition timing for your engine.
.

uberstang1

As far as the compression is concerned that's what the original owner told me it is at.

barnett468

assuming he is correct then its still too low.