6 replies to this topic

[wjrhodes]

Hi
Just started working on the tuning of my lads mini. Can anyone help with the best timing and distributor for it. The engine number is 12h702e-h21962 we were told that it is a 1275 possibly enlarged to 1310?
Thanks
WR

[carbon]

12H702 sounds like it may be a A-series block (not A+).

 

Does distributor clamp have two 1/4'' UNF bolts holding it on to the block adaptor, and do you have a distributor already fitted?

[wjrhodes]

Yes it has the 1/4' unf bolts, has a 25d fitted and a spare 45d so I'm not sure which one should really be on the engine. My Haynes says it should be 45d for the 1275?

[dklawson]

There will be additional information on the distributor housings.  Look for 5 digit numbers beginning with "4".  Once you have located those digits, look the numbers up in the PDF document linked below.

http://www.starchak..../pdfs/lucas.pdf

 

There are multiple advance curves for the 25D and 45D distributors.  You need to know which curves your two distributors have and then make some educated guesses about which is right for your engine based on what you know about how it was built.  Failing that you need to try both distributors and see which you like better.  The distributor won't be right or wrong for your engine simply because its model is 25D or 45D.

[carbon]

WR - could be either a 25D or 45D on a 1275. Early 1275's used the 25D, later ones (after mid-70s) used the 45D

 

As Doug suggests, check the 4**** numbers on the two you have.

 

It is very unlikely that either will be correct, and if you fit a different cam this will also make quite a difference to the timing requirements.

[wjrhodes]

Thanks for the helpful advice. Doing a swap on the weekend and hopefully get a good result. My guess is the 45d (which is in the car) is worn out and suffering from sloppy springs and play in the shaft.

[carbon]

Would recommend you check the 25D unit over before putting it on your 1275.

 

If the rotor arm and condensor are original Lucas items I would keep these, going by posts on this forum they are likely to give you much less bother than new replacements.

 

Also check that the vacuum advance is free, working, and no leaks while out of the car.