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Woody · 11-07-2002, 09:32 AM

Well these things just drive you crazy. From the description it idles well, and up to roughly half throttle runs well. Then above that it starts missing, backfiring, ect.

I went back and reread your post. The first thing I would change is that old COIL!!! they get hot and start breaking down.

So we need to start with basics. it needs 3 things to run, gas, fire In time), and compression. you have them until higher RPM. My suggestion would be to look at the dist., plug wires & plugs.
start with the dist. As it spins faster the wieght advance the timing. this could be causing problems. Also the coil & condenser are parts that don't like to sit around waiting for you to run them. They get old and start breaking down and when stressed, short out to ground. This could be your problem. Try to find someone who has a chevy and will let you swap dist.

Double Check the firing order!! mixing up plug wires is so easy.

Another idea is the valve adjustments. With the new cam you messed with the valve train so it deserves another look. Could be that the rocker were cranked down so much that as you speed up the engine and oil pressure rises, the lifters start holding the valves open, not until the higher RPMs though.

Good Luck

11-07-2002, 09:32 AM	#4
Woody Registered User Join Date: Feb 2000 Location: Georgetown, KY, USA Posts: 631	Well these things just drive you crazy. From the description it idles well, and up to roughly half throttle runs well. Then above that it starts missing, backfiring, ect. I went back and reread your post. The first thing I would change is that old COIL!!! they get hot and start breaking down. So we need to start with basics. it needs 3 things to run, gas, fire In time), and compression. you have them until higher RPM. My suggestion would be to look at the dist., plug wires & plugs. start with the dist. As it spins faster the wieght advance the timing. this could be causing problems. Also the coil & condenser are parts that don't like to sit around waiting for you to run them. They get old and start breaking down and when stressed, short out to ground. This could be your problem. Try to find someone who has a chevy and will let you swap dist. Double Check the firing order!! mixing up plug wires is so easy. Another idea is the valve adjustments. With the new cam you messed with the valve train so it deserves another look. Could be that the rocker were cranked down so much that as you speed up the engine and oil pressure rises, the lifters start holding the valves open, not until the higher RPMs though. Good Luck Last edited by Woody; 11-07-2002 at 09:34 AM.