Re: Timing Question about 5682s

Posted by Tim Cole On 2013/8/25 18:05:43

They were having detonation issues and started issuing distributor advance kits for customer complaints.

I wouldn't run anything except premium in those motors because they have high compression and a quench area that collects carbon.

The advance curves on those distributors really need to be checked on a machine because who knows what springs are in them.

When I was down in DC my modern car failed the stupid emissions test. It was slightly over NOX due to the cheap cat converter I put on it. The manual said running premium would improve performance. So I tried it and was surprised that the car really did run better.

I'm not interested at all in timing by ear. However, there are instances when it can't be avoided. In that case start with a good smooth motor speed and advance to the highest vacuum on a gauge, then back off 2 inhg mercury.

Otherwise put the thing on a dyno and hook a knock sensor up to a scope. You can also use the knock sensor and scope to set the timing on the road, but those old distributors really need to be checked.

I hate seeing those old motors being stressed by such problems.