Mechanics

TIMING?

1970 Chevrolet Nova • 79,500 miles

Car idles poorly after cam swap. When accelerating the car is very jerky almost like the car is flooded but the carb is tied way down. New spark plug wires and spark plugs. I think I might be off a tooth on the timing chain or cam itself
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Ichristensen
June 1, 2013.



What engine? 6 or8

Hmac300
Jun 1, 2013.
5.0 liter 307 v8
The cams a.470

Tiny
Ichristensen
Jun 1, 2013.
Have you put a timing light on this? And does it have points style ignition system on it.

Hmac300
Jun 1, 2013.
It's properly timed from the distributor. And it has a points eliminator kit on it

Tiny
Ichristensen
Jun 1, 2013.
The timing chain should be lined up dot to dot big gear to little one. Was the old cam damaged and you used the old lifters? If you bring it to tdc on #1 the dist should be at about 11: 30 on the clock. This could be a carb or vacuum leak issue as well. It could need a carb rebuild as well like maybe the float level is to high. You really should have a pro look at this you will probably end up saving money by doing so. YOu can look for carbon tracking or cracks in dist cap. If you lined the cam gears right that shouldn't be the problem. BUT if you put in a new cam and didn't put new lifters in then you might as well take the new cam out and throw it away also if you didn't lube the cam prior to install do the same. One other thing if it runs rough try to find out what cylinder it is then pull the valve cover off and look to see if lthe rocker is moving like the rest of them if you find one that isn't then it either bent a pushrod or something similar. Rocker arm adjustment on these unless it's mechanical cam is 1 turn down from zero lash.

Hmac300
Jun 1, 2013.