i just got my swap done on my cutlass and it is doing something i cant figure out. the car will be running absolutly perfect and then in a flash it will be running as if the timing was terribly off. i can give it gas and it will take off like a bat out of hell and then cut out then go then cut out. i have torn the carb apart and checked it, i replaced the cap and rotor, i have checked my firing order 3 times, i have swapped the fuel pump and checked pressure. alternator and battery is good, wires are good, connections all look to be good. i am mind boggeled. the engine is a 355 chevy with a bunch of performance stuff installed, vacum advance hei distributor, th350 transmission..... could the distributor cause it to do something this wierd? i drove it around for a hour 2 nights ago and it ran perfect the whole time, the next morning i drove it to work and it acted wierd all the way to work, at lunch it drove perfect again and then after work bad. i am stumped!
wierd issue with sbc 350
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i did check pressure when it was running bad, we had one of the gauges that t's into the line. what kind of electrical issue do you suppose could cause this?? i am wondering if the distributer may be shot....
regalman4925 said:
Maybe the distributor internals. theres ways to check them. if the internals turn out to be bad MSD has a kit that i did in mine to get a good spark above 5000 rpm.
The ultimate distributor.
These Ultimate HEI kits from MSD have everything you need to turn your early model GM HEI distributor into a great performance distributor. The MSD HEI modules feature special circuitry to produce 50 percent higher coil drive currents than stock modules, resulting in higher spark energy at racing rpms. By matching the coil specifications with the modules, MSD delivers more accurate timing and dwell control. The kits also include a high-quality rotor, a durable cap with brass terminals, and even a new dust cover.
http://store.summitracing.com/partdetai ... toview=sku
in the distributor all you have is the magnetic pick up coil and the modulator...I blew a the mod one time and the timing went all over the place from extreme backfiring to so far advance the car would barely turn over..I saw one at a track recently that only showed up with a miss at over 6000 rpm....
i am switching the modulator out as soon as i get home, hopefully its my problem. i read online that if it goes out it wont start at all but that sounds like its not true.
I had the same thing happen to me. I thought it was the module, so I replaced it. Same problem. What it was is going to sound funny, but check it anyways. The positive cable to the battery was loose where it connects to the starter. The starter on a G body is the main serial bus for the entire car, so by it being loose, it was loosing current throughout the whole car and thus, the ignition too. The odd thing was that the cable had been connected for 40k miles and never had a problem until it's first trip to the dragstrip -- 9 years after it had been assembled....
^^^...you could be right but he did say in his original post that.." alternator and battery is good, wires are good, connections all look to be good."
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