Re: Need Help Dont No What Else To Do
 

had an atv that did that, but the coil sparked bc of stator position, and it jumped timing, and it did EXACTLY what yours is doin. jumped like 3 teeth. pull dist and check On that style of atv, a lil raised pad acted as the rotor on your dist, so when it struck a certian point it fired, when the timing jumped, the valves would open at the wrong time, so it sparked wrong and ran like CRAP at idle, get up in rpms and it went away, but was a lil down on power.

Re: Need Help Dont No What Else To Do
 

ok the backfire...is backfiring out the exhaust or popping back through the carb? back through the carb is typically a lean condition...what carb is on it? its possible that while cranking it when it was wet it crossfired and spit back thru the carb and damaged something...blew off a vacuum hose, damaged pcv valve or hose, power brake hose, carb gasket etc...now that its dry its running lean...also did you check the timing? if its way off or all over the place the timing chain could have skipped (original style plastic tooth ones were famous for that)...

Re: Need Help Dont No What Else To Do
 

What about the coil? I had similar symptoms after running my '85 out of gas - replaced everything but the coil (the fairly expensive part) and rebuilt the carb. to no avail, but IIRC a new coil fixed it right up.

Its a demon and we bought a new carb also and we checked the timing and it was fine
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Put a new coil in it
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Re: Need Help Dont No What Else To Do
 

check timing before you do anything

Re: Need Help Dont No What Else To Do
 

will check on this tommorow im running out of ideas

Re: Need Help Dont No What Else To Do
 

Bad distributor is my guess.

Re: Need Help Dont No What Else To Do
 

I read through the thread and don't think you mentioned yet, are you powering the HEI distributor with the stock resistor wire, or have you done the 12V solid wire modification to your wiring when you installed the HEI?

Re: Need Help Dont No What Else To Do
 

thats what im thinking

Re: Need Help Dont No What Else To Do
 

pulled the first plug cranked it till it shot out of first looked at the rotor and it was pointing to number one

Re: Need Help Dont No What Else To Do
 

i did the mod to 12v

Re: Need Help Dont No What Else To Do
 

has almost nothing to do with timing , check your timing

I can't test it with a light because it doesn't have a mark were you can check it with the light
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Re: Need Help Dont No What Else To Do
 

So took the truck out this morning and when it shifts or gets to a certain rpm it backfires when I keep it at that certain rpm it backfires ALOT
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Put a new coil in it
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Re: Need Help Dont No What Else To Do
 

Sure it does!
Clean off the balancer and find it.
THen check where your timing tab is. It'll be at 2 oclock or at 12 oclock. At 12 oclock you need to look behind the water pump for it.

Re: Need Help Dont No What Else To Do
 

Now there's a good starting point.

Let us know what it is OP.....Thanks

Re: Need Help Dont No What Else To Do
 

had a 74 monte carlo with a 350 it had a bad cam and it backfired through carb and exhaust had 3 or 4 bad lobes on it at 85 thousand miles . not saying its it but if all else fails something else to check

Re: Need Help Dont No What Else To Do
 

I had a similar situation last year , thought I fouled a plug so I did a tune up ( plugs and wires ) still same issue , replaced cap and rotor still the same issue , started looking into everything and I couldn't figure it out , and I tried evething before tearing into the internals , so for the hell of it I pulled all the plugs and found one that wasn't firing (new plug )replaced it with another new one and it fired right up no more issues , so it is possible to buy bad new parts .
I would also double check the to make sure all your plug wires seated properly , I've seen that multiple times . I like to feel a nice solid snap , and if it's not squeeze the connector down with some plyers for a good fit .
Just a few suggestions , probably stuff you already tried , but I know how frustrating things get , some times the easiest fix is to take a step back and let some fresh eyes take a look at it , might be something stupid . Good luck .
Sincerely, Doug

Re: Need Help Dont No What Else To Do
 

How did you do the test to determine it wasn't firing?