Author Topic: Engine trouble  (Read 299 times)

Offline Schimms15

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Engine trouble
« on: July 22, 2019 - 07:44:15 pm »
Hey guys I finally got a cuda and love it. It developed a problem recently though. When I accelerate from 2000-2500 rpm by putting the pedal to the floor the car launches then really jerks forward and back badly like Im going over the worst pot holes in the world. If I back off and use up to 90% throttle it is fine. It does it in that rpm band in every gear. Once it leaves that rpm band it rockets off smooth as could be.

I only use 91 octane fuel and have a 340 with a tremec.

My initial guess is a semi plugged jet in the carb. It was professionally tuned before I got it and I do have the sheet with all the numbers but I cant take it back there. Im in Wisconsin it came from New York.
Willys cj-2a 1946

Online 70chall440

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Re: Engine trouble
« Reply #1 on: July 28, 2019 - 12:12:47 pm »
Its either a fuel or ignition issue, more than likely a fuel issue as you suspect. Something plugged would exhibit problems across the RPM band I would think, you need to get it tuned where you are. It may be possible its getting too rich at the rpm band causing it to bog.
Current Mopar
70 Challenger RT 440-6 EFI, 73 Cuda 416-6 EFI
05 Hemi Durango, 01 Ram 4x4, 14 Ram 2500 4X4, 10 PCP Challenger 6 spd RT, 01 Viper GTS ACR, 52 B3B w/330 Desoto Hemi, 70 Hemi RR (under const)
Past Mopars
9 x Challengers. AAR Cuda, 4 RR, 2 GTX, 4 Chargers, etc... (too many to list)

Offline jimynick

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Re: Engine trouble
« Reply #2 on: August 08, 2019 - 11:47:23 am »
What kind of carb is on it? The Thermoquads were notorious for huge flat spots as sometimes they were "adjusted" and the air door popped open before the engine developed enough rpm to handle it. A mechanical secondary carb could also do that. What size is it?

Offline dodj

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Re: Engine trouble
« Reply #3 on: August 17, 2019 - 07:17:43 am »
I'm kinda thinking it must have something to do with the accelerator pump linkage or maybe secondary diaphragm issues if a vacuum carb?
1973 Challenger  440 4 spd 
2007.5 3500 6.7 Cummins Diesel, Anarchy tuned.
Good friends don't let friends do stupid things. ........alone.