Author Topic: 351W popping thru carb  (Read 379 times)

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Offline mustangtrio

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351W popping thru carb
« on: June 11, 2017, 02:56:19 PM »
Ok. A friend has a 351w in a boat. 1991 model. We put a set of about 69 stock heads(big plugs) on it. Hyd lifters with adj rockers. Dual plane weiand. Ithas a 302 firing order instead of 351. This firing order came from factory. I can only assume it is a 302 cam. Won't run well at all on 351 order. It will start right up and idle beautiful and will rev perfect and crisp in nuetral. Timing at 10, total advance to about 30 (estimate since balancer is not marked past 20). No movement at all in timing mark which would indicate not a sloppy chain. When u put it in gear it definitely loads motor and when you accelerate it pops thru carb constantly.as u try to accelerate the motor will not come up and the timing won't advance.
I have checked for vacuum leaks,installed a new 600 edelbrock carb, replaced dist,plugs and wires. I tried unplugging 1 plug wire at time and putting under load but it still pops. I figured if a valve issue disabling that cyl would stop popping. Ran compression check and all showed close to each other. If a valve issue would it not pop when ran up in neutral without load?
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Offline twinturbo

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Re: 351W popping thru carb
« Reply #1 on: June 22, 2017, 07:43:05 PM »
Coil is bad
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