Author Topic: Carb help!!  (Read 10 times)

Offline TFlynn72

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Carb help!!
« on: Today at 10:09:20 am »
I have a Cuda with 440, Medium cam, bored .30 over, factory heads but valves have been enlarged, headers. My question is I have a 850 Holley dual pumper and it seems like it may be to much for the motor? What do you think is a good fitment for this engine if it was yours. It does run rich. Thanks!!!!

Offline 70chall440

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Re: Carb help!!
« Reply #1 on: Today at 02:24:58 pm »
I am sure you will get a variety of opinions here but IMO an 850 is too much carb for a mild motor. a lot has to do with how you use the car; are you racing it or just driving it? You could probably rejet the carb to get it to run leaner, adjust the timing, etc. I would probably run nothing more than a 750 or maybe even a 650. You really need a wide band O2 sensor/reader to really dial it in. Plenty of guys here have and are running carbs on 440's to provide much more accurate advice. In my case I normally ran 6 packs on my 440's and relatively recently went to EFI on everything.
Current Mopar
70 Challenger RT 440-6, 73 Cuda (under const)
05 Durango, 99 Dakota, 01 Ram 4x4, 14 2500 4X4, 10 PCP Challenger RT, 01 Viper GTS ACR, 52 B3B w/330 Desoto Hemi, 70 Hemi RR, 61 Jeep FC170
Past Mopars
9 x Challengers. AAR Cuda, 4 RR, 2 GTX, 4 Chargers, etc... (too many to list)

Online jimynick

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Re: Carb help!!
« Reply #2 on: Today at 09:46:31 pm »
They ran 850's from the factory in Thermoquads, so it may not be the carbs fault alone. Having the ability to determine the actual fuel/air ratios in a live environment is necessary to make the tuning task easier for mere mortals. The power valve and it's rating and functionality are also a key aspect and it's tough to just guess your way to success. If you can find a shop with a chassis dyno and a sniffer you'll be a lot closer to your goal, Good luck  :cheers: