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Discussion Starter #1
heres a video of the problem

can anyone tell me why its doing that? its got a 454 bb, holley 750 carb.

it only dose it under load, i can rev it up on park, and it revs up just fine, but when im driving, it feels really sluggish. something is wrong, just dont know where to start.
 

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Simple check first!

Check total timing!

If running vac advance where do you have it hooked up??

Is firing order correct? 5-7 crossed.

Do you have any plug wires against header? Age and condition of plug wires?

Water in dist cap? Cracked cap?

Good luck
AL
 

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Dont forget to check

Dont forget to check your float levels.
If to low could be starving for fuel.
 

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Simple check first!

Check total timing!

If running vac advance where do you have it hooked up??

Is firing order correct? 5-7 crossed.

Do you have any plug wires against header? Age and condition of plug wires?

Water in dist cap? Cracked cap?

Good luck
AL
I agree with Al. Especially the one I have highlighted! Mine sounded exactly like that!
 

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floats

i'd check the float levels in the carb ,, but really i'd go over it from top to bottom. Check the back fuel bowl and see if its getting gas in the bowl at all.

sounds like its running on bad gas , so i'd check the timing as was mentioned. If it sounds good at idle , but not under load , thats usually fuel delivery , or too much timing related, or quality of your fuel.

i'd take a timing light and go around the cap checking each spark plug wire and make sure they're all firing at idle.

I would pull the valve covers and observe the rocker arms to make sure they're all traveling the same amount. Might be a bent pushrod or a bad cam too or broke valve spring.

As bad as it sounds , i'd go all over it.

i'd check the valve adjustment too ,, hyd or solid ??

When did you first notice this and what had been done to it just prior to this going on ?? Do a real hard pull on it then it started making this noise ???
 

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Discussion Starter #9
ok half of the wires are lightly touching the headers. im not sure if its 1357, or 2468, but half are positively touching, i pulled them off my small block, and they are msd 8.5 about 4 years old.
 

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Discussion Starter #10
and where should i be at to start setting up the timing? i just realized we only adjusted it so that it would start, i never actually pulled the timing gun out and checked. :eek:
 

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Mine wants to run best at 12 to 14 degrees intial and 34 to 36 degrees total with all of it in by 3000 RPMs.
 

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Discussion Starter #13
ok so im running these E3 spark plugs with .440 gap, and it feels like the new wires are not clamping on the spark plug to great. has anyone experienced that issue??

wires are msd 8.5 super conductors.

also ran the car, and it feels exactly the same, and no wires are near the headers.
 

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Discussion Starter #15
i'd check the float levels in the carb ,, but really i'd go over it from top to bottom. Check the back fuel bowl and see if its getting gas in the bowl at all.

sounds like its running on bad gas , so i'd check the timing as was mentioned. If it sounds good at idle , but not under load , thats usually fuel delivery , or too much timing related, or quality of your fuel.

i'd take a timing light and go around the cap checking each spark plug wire and make sure they're all firing at idle.

I would pull the valve covers and observe the rocker arms to make sure they're all traveling the same amount. Might be a bent pushrod or a bad cam too or broke valve spring.

As bad as it sounds , i'd go all over it.

i'd check the valve adjustment too ,, hyd or solid ??

When did you first notice this and what had been done to it just prior to this going on ?? Do a real hard pull on it then it started making this noise ???
the first time i ran it, it was open headers so i took it really easy. once i welded up an exhaust, i tried a hard pull, id say 3500rpm max, and that's when i started noticing the funny feeling, and it just got progressively worse.


by checking the valve lash, am i looking for a loose rocker arm, or an over tight one??
 

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Simple check first!

Check total timing!

If running vac advance where do you have it hooked up??

Is firing order correct? 5-7 crossed.

Do you have any plug wires against header? Age and condition of plug wires?

Water in dist cap? Cracked cap?

Good luck
AL
Al has given the best advice.
My car sounded just like that.
It was a combination of 2 burnt plug wires and a damaged distributor, base was bent and rotor snapped from tranny install when it leaned against the firewall.
 

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steel rat how did you figure out your dist was damaged?? now i have a miss at 4000 rpm,popping throught he exhaust,only when i'm on it hard,if i'm cruiseing on the highway and just ease it up to 4000 seems okay,,just got mine back from the trans shop and what do you know it runs like crap,i replaced the cap and rotor but still popping??? timing is good...
 

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steel rat how did you figure out your dist was damaged?? now i have a miss at 4000 rpm,popping throught he exhaust,only when i'm on it hard,if i'm cruiseing on the highway and just ease it up to 4000 seems okay,,just got mine back from the trans shop and what do you know it runs like crap,i replaced the cap and rotor but still popping??? timing is good...
It is an HEI dist so first I replaced the modulator, then the cap, each time no improvement. So thinking it was pick up under the rotor plate I headed back to the parts shop. And they had entire HEI for 80.00. So the old one was pulled and upon inspection saw the base warped, and the rotor would freely swing 60 degrees each way. My tranny builder who did pull the cap thinking that would be enough when the tranny was pulled, was unaware the motor tipped back enought to bend the base and have the rotor make contact with the fire wall as well. He reimbursed me for the distributor, parts and 1 hour labour at a local shop who set the timing, tuned it up etc.
 

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thats the result i would like to see but doubtful. tranny guy said they took the cap off i just wonder if that was after they had the distributor hard agaist the firewall..the cap had no visual crack in it but it's pretty suspicious when you get it back and it runs crappy,was fine when i left it there.i have another hei so i will piece it together and try that,i also have a plug wire that may be part of the problem i'll try that first.
 

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Good luck, It was frustrating for me too, but in the end it was fine. Then other things occur... as they alway do :)
 
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