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Discussion Starter · #1 ·
hi guys im a new user here. ive used this site alot but never posted. im trying to figure out a miss ive been having. i have mildly built chevy 350 in my cutlass. its a 397010 4 bolt. bored .60 over. flat top pistons, all clevite bearings, 882 heads 1.94 1.60 valves. .500 lift flat tappet cam, holley contender high rise dual plane intake with a holley street avenger 670 carb. im running an accel distrubutor with the guts taken out to accomodate the msd box im running. producing about 10.5/1 compression. i have the lightest advance curves springs on the distributor. im running accel shorty plugs at .45 gap and msd super conductor wires. this was all built 2 months ago. my problem is while cruising down the road i have a miss. it goes away when push or let off the throttle. it idles great. ive checked all the plug connections, none of the wires are touching. im thinking it may be a lean issue from the carb. ive heard the street avengers run lean. any ideas and any info and feedback would be great.
 

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Discussion Starter · #3 ·
yeah thats a good way to check for arching. im thinking maybe i have a fouled plug. when i rebuilt the carb i didnt have the right metering gasket in and it ran very rich and wouldnt stay running. i did take the plugs out and clean them up. could this be the issue?
 

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jj7ski said:
hi guys im a new user here. ive used this site alot but never posted. im trying to figure out a miss ive been having. i have mildly built chevy 350 in my cutlass. its a 397010 4 bolt. bored .60 over. flat top pistons, all clevite bearings, 882 heads 1.94 1.60 valves. .500 lift flat tappet cam, holley contender high rise dual plane intake with a holley street avenger 670 carb. im running an accel distrubutor with the guts taken out to accomodate the msd box im running. producing about 10.5/1 compression. i have the lightest advance curves springs on the distributor. im running accel shorty plugs at .45 gap and msd super conductor wires. this was all built 2 months ago. my problem is while cruising down the road i have a miss. it goes away when push or let off the throttle. it idles great. ive checked all the plug connections, none of the wires are touching. im thinking it may be a lean issue from the carb. ive heard the street avengers run lean. any ideas and any info and feedback would be great.
With FT pistons I doubt the CR is going to be that high. But in any event, the first thing I would do is to get a new set of plugs in it and see if that fixes the miss.

If not, a few things that you can look into:

The rest of the secondary ignition system- cap, rotor, etc. Be sure there are no wires running parallel to one another and that the wires aren't burned/laying on the headers.

Use dielectric grease on the boots on both ends of the plug wires.

Set the timing curve up. This is a major part of how the engine runs- from idle all the way up the rpm range. Typically, too much advance can cause a "surging" that

More on that here. The article is about the HEI, but the advance curve info holds true across the board except that some engine combos need more or less timing at the various points.

You can look at the rotor phasing if all else fails.
 

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Discussion Starter · #6 ·
Yeah I. Wll buy some new plugs. What do youb mean make sure they don't run parallel? With the use of wire looms they all run parallel. I have a stock replacement accel distributor with the module taken out. I have the msd box hooked up to the magnetic pickups. The cap and rotor are brand new. I got them from carquest and don't think they are a major brand. But what's the difference? I believe the cap may have aluminum contacts. So I should get one with brass contacts? Also I had the engine built by a professional race engine builder. He said the cr is 10.5-1. No reason not to think it is. The block and heads have been milled to achieve this. Is there a way to confirm the cr? I don't know how to check. Thanks for the feedback guys
 

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Discussion Starter · #8 ·
Well changed the plugs and the right side was black and had oil on them. It got a little better but its still there. I guess my next step is getting better cap and rotor. So whts the deal with oil on my plugs? It doesn't smoke so where could that be coming from?
 
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