Thread: Tracking down a miss?

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I have a 350 sbc 90blck with 84 heads, it has a lunati .480 lift cam with a edelbrock eps manifold. It did have a performer rpm which was way to big and took alot of my vacumn. Well i was on the road for about 6months came back and it cranked right up, i decided to change the manifold(to the eps) did that i have reset the timing and everything rebuilt carb also! The miss didnt start till after i changed manifolds. I just wanting any info on finding the miss instead of replacing everything peice by peice! It has accel wires and coil on it and rotor which are all about a year old! Platinum plugs also about a year old!

This is a cool website, wish i had found it long time ago!
Thanks for any help in advance!
Godzirra

you can pull wires off one at a time to see which cylinder is missing....then check out plug....and or wire...

I just pulled a few plugs, they dont look to swift so think ill just replace all of them! I have to take my headers off thou
Could the little module inside of the distributor b causing this its about the only original thing on the distributor i should pull it and have them check it when i get my plugs!

Well i think i got the miss solved, i set the timing by ear for now but iam going to bust out the timing light tomorrow! I have another problem when i give it some gas it stuumbles tried playing with the idle mixtures and all! Its a holley 750 single pump with vacumn secoundaries! This is my first holley to actually run and try to understand them or learn about them! I used to use edelbrocks carbs on everything!
thanks godzirra

the stumble sounds like your accelerator pump is weak

How should i go about makin shure its working properely!
Thanks
godzirra

the best way is just replace it......you dont have to buy a kit....you can just buy the pump...useally they get a small wear line..

It is very hard to start takin more the 4 pumps of the pedal to start, but once it is up and runnin it runs very rich! I just put a new accelerator pump in when i rebuilt it! I have another one that came with the kit ill put it in and see what happens.I let it set in berrymans chem dip so the check shouldnt be stickin, but i kinda wonder if it is! Iam thinkin about ordering a new mainbody, i bought this carb used and its had some wear and tear, the blades have worn into the side of the barrels a little, prolly the reason why the idle circuits act so strange!How hard would it b for a holley newbie to change mainbodey?
thanks for the help

you should be able to pump once to set the choke........re-adjust your choke..this will stop your 4 pumps

It has no choke! Tee-Hee
Godzirra

thats why your haveing starting problems

hopefully this will help you if you have not already found the problem it would be that your intake gasket did not seal right had the same problem stumbles hard to start running rich ect.... changed plugs wires cap button .ign system fuel system had carb rebuilt. everything you could think of pulled intake off you could see where it was leaking new gaskets fixed the problem hope this helps

Well i think my cam has jumped timing! It backfires when i give it fuel, and backfires bcuz of richness thru exhuast! When i try to check timing, i never see the timing mark but my timing light is acting a little strange so i bought a new one will check timing again tonight! Yes no vacumn yata yata...

I know you already said you found you miss but here is another easy way to find a miss. After it has sat and is completly cold crank it for a few seconds (10 seconds with headers) (20 seconds with exhaust manifolds) then go under the hood BE CAREFULL should just be warm but feel each runner on the exhaust, the cylinder thats is coldest is were your miss is.

yep. same problem i had.back fire no vacum. ran like sh.t i would start there save you a big headache. cant say that cars will always be a headache good luck ... gess i was not paying very good attention to the post sorry