setting my timing

[fireZ]

I have tried to set the timing on my 68 z at 4 BTC but the car will not run. I put the timing to 9-10 BTC and the car runs great,also total timing is at 32 at 2900 rpm . Any ideas why it will not run at the recommended 4BTC   

[CNorton]

Have you verified that the timing mark on the damper is indicating a true TDC?  The outer ring of the damper can slip on the rubber ring of the hub and provide a false reading.

[fireZ]

Thanks for that idea

[JohnZ]

Use a piston stop tool to verify #1 TDC vs. the alignment of the index mark on the balancer ring and the "0" on the timing tab. On a '68, the index mark on the balancer ring is exactly in line with the keyway slot and pulley bolt, and the index mark moved 10* counter-clockwise on '69 balancers (and the timing tab on the cover moved to match) when they went to the long water pump accessory drive system with the passenger side alternator.

[mikefam]

What do you mean when you say that it won't run? Does it become very rough and stall?

On the surface it sounds to me like you have a large intake vacuum leak or electrical problem. I'd do a major tune up before trouble shooting.

Mike.

[fireZ]

I figured out that the car has the wrong timing cover on it. It is a 69 cover were the timing tang is 10 degrees off from a 68 Z