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4,346 Posts
I'm not trying to start an arguement...
You've been very vague to this point, and I was just trying to help.

If you can't get your timing correct it's going to be hard to figure out the source of your problems. That's all I'm trying to say. Timing should be the first thing you always check.

Timing by ear almost always leads to over-advancing...and if your timing mark is showing up near the top of your motor (and your timing tab is in the common 2'oclock position) you've likely got your ignition timing over advanced be at least 15-20 degrees. THAT is a problem.

When all else fails...look up the factory specs and work from there. I am yet to see a repair manual that says "Fire up your engine and turn the distributor until it sounds good."
It just doesn't work that way.

My point is you need to set your timing properly. Then move on to everything else--do your repairs in a methodical fashion to avoid "fixing" things that don't really need "fixed."

Be aware that altering your timing may require adjustments to your idle speed and air/fuel mixture.

Loosen the distributor hold-down until the distributor can be turned (but ramains somewhat snug).
Disconnect and plug the line to your vacuum advance.
With the timing light hooked up, and on the #1 cylinder, line up the mark on the balancer to 12-14° BTDC on your timing tab.

6 Posts
Ok. I have a 75 Nova that has been completely rebuilt. Running a Holley 670cfm street avenger with an edelbrock dual plane performer RPM intake. Recently installed a 1" carb spacer. When leaving from a stop it acts like it is starving, almost dies, then roars back to life. Can't tell if it's starving or flooding. But on acceleration it misses on one or more cylinders. Once it reaches the higher(3,000+) RPM ranges it does fine. And at stops I have to put it in nuetral or it will die. I thought maybe the idle was set too low but it idles at 1300-1400rpm. Ive tried adjusting the timing, but it doesnt help. I time it by ear to when it seems to run best. I did find one spark wire that is sparking against the headers. Would that cause that big of a problem? I was also thinking that the fuel pump may not be putting out enough. Any help is great.

Here are the total specs I know about the engine.
350 4 bolt main motor is brand new rebuild,
high compression forged flat top pistons,
hyd roller elgin cam, valve lift .450 int. .460 exh.,
1.5 roller rockers,
bigger valves on heads.
piston chambers bored out .40 over,
stronger push rods,
forged crankshaft.
brand new holly street avenger 670 cfm carb.

And here are the specs on the cam
lobe int. - 114 exh. 114 .
SAE dur. - 292 int. 288 exh.
.050 dur - 224 int. 224 exh
SAE timing - BTC 32 ABC 80 BBC 78 ATC 30
0.50 timing - BTC -3 ABC 47 BBC 46 ATC -2
Make sure your plug wires are not cross firing!
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