Thread: Problems With Idle

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I have a .060 350 sbc. 10.1:1 compression. Comp 280 cam. Weiand stealth ram, rblt Holley 570 (64pri, 72sec), an MSD street fire Dist, rblt stock heads 1.94int 1.50 ehx i believe. In a 69 chev c-10 w/ a th350 and 4.11's out back. My stall is at 2800.

Ok here's the problem I've been fightin with: It doesn't like to idle lower than 1000rpm in park. I've gotten it to 900 but no lower. In gear it will not stay running, it'll just stall an die. Also, when i'm drivin if I punch it, it spits an sputters over 3200. And finally, every once in a while it'll pop through the carb and kill the motor- this was worse when i had 87 oct fuel, i have 91 now.

I've adjusted timing (i'm at 8 on idle), tried leaning the carb out, I even changed the int gasket cuz of a suspected vac leak.

Do i need to pull more timing, re-curve the dist, valve lash or is it somethin else?

what is your total timing?

Is your vacuum canistor hooked up and to where on the vacuum. I run a 327 with the comp 280 cam but with the Q-jet. Love that cam.

have you checked your float level on the carb.I had alot of the same problems your having and it turned out the float level was low on the secondary bowl.had a real ratty idle and was cutting out at high rpm.didnt know I had a problem until I hooked up the passing gear.when level was corrected the idle was much more adjustable and consistant.the 280 cam will still give you that lopy idle . good luck

Either lean or retarded spark. I'd try more advance, if that doesn't do it, check real close for vacuum leaks, then richen the carb.

Reread your first post. Re-adjust the valves, don't turn them down as far as you have them now. Some lifters don't like being "crowded", regardless of what the specs say. That's assuming you have juice lifters, of course.

What's your vacuum reading?

I'm not sure what my total timing is, or how to check it. I don't have a vacuum can.

Thanks everyone for your help!!

OK no vacuum can. Re-adjust the valves and re-check your timing. Initial timing should be 12 advanced and total (rev engine to around 2500 to 3000 while watching the timing mark) around 32 to 35 advanced.

Have you checked your vacuum idling in drive? Are you running the power valve that came with the carb? Many, if not most street Holleys come with a 6.5 power valve. If your vacuum is less than that at idle, you load up at idle. I was washing down the cylinders and my oil was full of gas within a few miles. Finally figured out the problem but ended up tearing down the motor to replace the bearings. Vacuum, power valve. One more thing. All the books I bought about Holley carbs, the best was the big fat Holley catalog I got free at a car show. Maybe you can get one from Holley's web site.

I've rebuilt that carb, and I did change the power valve. I believe it to be the same size as i pulled out. it had a 6 stamped on it, if i'm remembering right. Gonna garb my timing lighta and try changin the timing to 12. then i'll check vacuum numbers and get back to you guys.

Thanks for the info, and i'll look for for that catalogue.

Originally Posted by Warpig7

I have a .060 350 sbc. 10.1:1 compression. Comp 280 cam. Weiand stealth ram, rblt Holley 570 (64pri, 72sec), an MSD street fire Dist, rblt stock heads 1.94int 1.50 ehx i believe. In a 69 chev c-10 w/ a th350 and 4.11's out back. My stall is at 2800.

Ok here's the problem I've been fightin with: It doesn't like to idle lower than 1000rpm in park. I've gotten it to 900 but no lower. In gear it will not stay running, it'll just stall an die. Also, when i'm drivin if I punch it, it spits an sputters over 3200. And finally, every once in a while it'll pop through the carb and kill the motor- this was worse when i had 87 oct fuel, i have 91 now.

I've adjusted timing (i'm at 8 on idle), tried leaning the carb out, I even changed the int gasket cuz of a suspected vac leak.

Do i need to pull more timing, re-curve the dist, valve lash or is it somethin else?

It'll never run right at 8 degrees intial timing. Crank the timing up to 16 degrees base since the distributor has 20 degrees mechanical advance. That will give you 36 degrees total. Then you need to get a timing wrap and mark your balancer at 36 degrees BTDC.... or get a dial back timing light. You want the full advance of the 36 degrees to be all in by 3000 rpm. Find the combination of springs it takes to get there, try the medium springs. If you don't have the springs that came with the distributor, they are MSD Part No. 8428 http://www.msdignition.com/product.a...479&terms=8428

That sure is alot of timing ray, are you sure I need that much? But i do have the spring kit for the dist. I've been told i need to re-curve it I just haven't done it yet.

I'm positive that it needs that much timing. This isn't a stock engine, it has a nice cam in it and it requires more timing at idle. Don't try putting 87 gas in it. That's too low of octane for 10:1 compression.

Timing can make or break an engine. Too low of timing will do everything your's is doing now. Set the timing up as described and it will be a different animal.

Thanks for your help Ray!