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MG MGB Technical - Plug gap with pertronix

Hi,
What is the ideal plug gap setting with a pertronix ignitor and a 40k coil on a 1972 B 18V engine ?
Regards,
Barry
Barry 72B

Barry a 40K coil is good for 35 thou on a high comp B.
Denis
DENIS H

Thanks Denis, Barry
Barry 72B

Barry,

Mine gab is set at .038 with the same set up you have. This is what the instructions stated I believe for the ignitor and a 40,000v Flame thrower coil.

Ray
Ray 1977mgb

No more than .035 - the cap and rotor are the limiting factor, and the 23/25D caps don't like any more. The 43/45 caps are a bit better - that's why they are bigger.

FRM
FR Millmore

Thank you all,my car is a 72 with 25D distributor so better keep it 35 max.
Barry
Barry 72B

I was going to vote for 35 thou. The NGK website gives this for the Fiat with it's coil per set up.
Stan Best

The gap went up from 25 to 35 with the change from 25D to 45D and its better cap and rotor (the 45D is actually physically smaller than the 25D). So strictly the gap with a 25D should be 25 or you could get breakdown problems.
Paul Hunt 2

Paul,thanks for your usual detailed comments, I spoke to Pertronix and there advice was to go the extra 0.5 to 0.30 max.
Barry
Barry 72B

This thread was discussed between 11/06/2007 and 13/06/2007

MG MGB Technical index

This thread is from the archive. The Live MG MGB Technical BBS is active now.