MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGB Technical - 25D4 pertronix ignitor in 45D4?

I've recently purchased a 45D4 "euro-spec" distributor from Brit-tek for my 1969 B. I bought the car with the pertronix ignitor electronic ignigion installed...Upon closer inspection the mounting plate I have in my 25D4 distributor doesn't look like it will fit into the new distributor. From what I've read thus far it seems like the "electronics" of the ignitors are all the same, it's just the mounting plates that are different. Does anyone have experiance modifying the plate that fits the 25D4 to fit into the 45D4 or do I need to fork over some cash for a new electronic ignition.
Any advice will be appreciated.
-Bryan.
Bryan Fournier

Brian. I am not a fan of these systems myself, so do not have a great deal of experience with them. I recently helped a friend install one on a 25D and, while we were at it, examined how the shutter would fit on a spare 45D. The points cam seemed to be significantly different. (As might be expected with the 25D having a 60 deg dwell and the 45D a 51 deg dwell.) So, I know the shutter unit from a 25D kit does not work on a 45D and your examination seems to indicate that the base plate looks like it will not fit. Probably a very good chance that the 25D kit is not going to fit the 45D without some major modifications and adaptation. Les
Les Bengtson

There are different versions for different distributors. At least, I thought so, but I can only find part numbers for 75 on. I have heard of some people havoing to mangle the points plate to fit one, which is a bad idea as one should always carry a set of points and a condensor as a spare - and be able to fit them!
Paul Hunt

Interesting. I have had a unit for both types of dizzies, and the base plates and the magnetic collars which fit over the cams seem to be the only real difference that I can see (since you cannot go inside one of these encapsulated trigger units). The breaker plates for the 45D and 25D series dizzies are nowhere near the same in design, and because that is true, the mounting plates for the triggers are not close enough in shape and fixture to be exchangable.

As for mangling the breaker plates; both units I have installed required NO changes be made to the breaker plates to be installed, making them ideal choices for those who want to be able to revert to Lucas points in an emergency. Perhaps the folks who mentioned this problem were confusing the Pertronix units with those used with the Crane XR-700 "Fireball" ignitions, which I have also installed. That brand's trigger unit does require modifying the breaker plate by removing the points pivot post on 25D dizzies? Could be.
Bob Muenchausen

This thread was discussed between 30/04/2003 and 02/05/2003

MG MGB Technical index

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