1963 Distibutor advice

[Jeff C.]

Engine is 1963 340HP unknown solid lifter cam and actual compression ratio. Distributor is at least correct for engine and I have Dukes recommended vacuum advance B-28. I am not looking for 7000 RPM Max HP but a nice to drive car. So the bottom bearing on the distributor main shaft has more than .002 play in it, how much I can not measure. How will this affect normal engine operation/driving?
Thanks,
Jeff

[Edward J.]

Re: 1963 Distibutor advice

Jeff the b-28 vacuum can will help the engine run better all around, as for the play in dist.bushing any is not good, what is your dwell doing, with a meter attached run at idle and at about 2500rpms, If there are some fluctuations, there's a chance there will be a driveabilty problem.

[Duke W.]

Re: 1963 Distibutor advice

Are you talking about the lower bushing side play? What about the upper bushing? End play should be in the range of 2-7 thou. The breaker plate should fit snuggly on the dist. housing with no "wobble". Check for spark scatter at idle and higher revs. Excess side play or end play will cause spark scatter that you can see with a timing light. If everything is snug there won't be any, which yields a smoother running engine. If you can't remember the last time the dist. was overhauled, now is the time. Search for a thread started by me in Dec '12 about this subject.

As stated previously also check for dwell variation at high revs. It should not be more than 2 degrees.

Also, the '63 340 HP centrifugal curve is Lazy - 24 @ 4600. Bringing it in earlier with light springs will improve low end torque. Spring and shim kit part numbers are in my tuning seminar pdf.

Once lighter springs are installed, set the total WOT timing with a dial back timing light (VAC disconnected) a few hundred revs above the point of max centrifugal as high in the 36-40 range as the engine will tolerate without detonation.

Duke