Over achieving distributor

[doug noll]

My '72 B has the proper 25D4 #41491 distributor.
By timing lite measurement it has 42 degrees
internal advance. This gives a beggars choice of
proper initial advance and way-too-much total
advance with piston-wrecking spark knock, OR
way retarded initial advance with good power and
very poor idle, acceleration, and surge at cruise.
Has anyone out there experienced and fixed the
same problem? How about reducing the internal
advance with two heavy advance weight springs?
How about bending the spring posts to make the
advance weights work harder? Who's done the job
and solved the problem?
Thanks in advance for your input.
Cheers,
Doug Noll

 

[Dennis P]

Doug, Checked the Moss guide on page148 of the 4/8/02 catologue and your dist is for the 73 on low compression, V engine. 72 calls for dist#41370. The difference in these dist is the adnace rates, even though they are all 25d4s.

 

[doug noll]

Dennis,
Good eye, sir, and correct of course. The car
is indeed a '73, and the distr. is correct per
the Bentley manual. 'Seems the dummy operating
the keyboard at this end missed a stroke.
While off this forum, we've gotten the information
that there is a Mr Gasket kit for GM HEI distrib-
utors that has 3 sets of advance springs for fine
tuning purposes, that has parts compatible to
Lucas distributors. I'm now chasing the kit part
number, and hopefully soon will be able to tune
on my car.
Cheers and thanks,
Doug Noll

 

[Dennis P]

Go to the Summit catalogue and the kit is there for about five dollars and my reading shows also they are used in place of
lucas.