I bought a carb on ebay that was built for 350 when i swithed it, I was shocked at the new power i gained WOW! wide open it is awsome.But when i start it it runs real bad cold so i swapped the electronic choke from my old one which worked great at start and really bad when warm.The car still runs bad when cold at start.what should i check out.what is the name again on that book for these cc controlled carb


Thanks, Dave

 

When the engine is completely cold, before you turn on the switch, the choke should snap completely shut when you open the throttle a little. After starting, the choke should open a slight bit via the vacuum pull-off. After a few minutes of running, the electric thermostat should warm up enough for the choke to be fully open.

If all three conditions aren't met, you'll have: a) hard starting, b) stumbling, stalling, etc. before warmed up, or c) poor power when warm.

The typical culprits are: No power to thermostat; bad thermostat; bad choke pull-off; dirty mechanism. Or, mis-adjusted any of the above.

Check those things out and see if your problems go away.

------------------
82 Berlinetta, orig V-6 car, now w/86 LG4/TH700R4, 2300 stall TC. Ported World 305 heads, Crane PowerMax 2050 cam. ZZ4 intake, oil pump, pan & baffle. Accel HEI SuperCoil & module. Hooker 2055 headers, 3" Catco cat & 3" catback w/dual-opposite Flowmaster 80. 2.93 limited slip. Spohn SFCs waiting to be installed. AMSOIL syn lubes bumper-to-bumper. Daily year-round driver. Best ET, speed TBD...
57 Bel Air, my 1st car. '66 396, 9.7:1 forged TRWs, Weiand Action+, Holley 750VS w/4150 conversion, GK 270 cam, Magnum rockers, Jacobs Omnipack, 1-3/4" Hedders & 3" Warlocks, TH400 w/TCI Sat Night Special conv & Trans-Scat shift kit, MegaShifter, 3.08 8.2" 10-bolt w/Powertrax, AMSOIL syn lubes bumper-to-bumper. Idles smooth @ 700 RPM in D. Best 15.02/95.06 @ 5800' Bandimere (corrected 13.93/102.4 @ sea level).

 

I checked the operation of the choke it works.it is closed when first starts then gradually opens fully. if i start it and let it warm up for 5 -10 minutes it is fine. but if I try to not let it warm up completly it stumbles and some times stalls. The choke seems to work it starts and holds idle, just when you try to drive it it starts stumbling until it warms up.

 

What kind of air cleaner do you have? The stock factory piece has a warm air diverter to help ease that problem. If it isn't working/hooked up, or if you have an open element, you won't benefit from that feature.

The other possibility is the choke pull-off is pulling the choke too far open, or possibly not far enough. That is easy to adjust, a screw on the arm that contacts the choke lever to open it. There is a setting for that, but I just tend to adjust it to open more/less, try it for a day or two, readjust next day, etc., until it runs right.