-91A Oil pump retrofit pre -90?

[xlfan]

Has anyone retrofitted a stock -91 up oil pump on 86-90 4 speeds?

Zippers has a 3-stage pump that will retrofit 86-90 with an oil fitting kit? Could that be possible with the stock pump as well?


xlfan

[andyxlh]

Not sure, I remember reading something about not being able to do that with 4 speed evos, but I know it is in a book I have by Kip Woodring and Kenna Love (funny how you remember the odd author names) called something like 101 evolution performance projects (or something like that). Great book, Love also wrote another on sportster performance which is also excellent. I have a copy of both at home, I'll have a look this evening to see if I can find it. I think that the cases are different and therefore I guess the mounting holes and the pump drive shaft would also be different. Funnily enough I was thinking what I'd do with my oil pump when I do an engine rebuild on my '89 later this year, I was resigned to replacing the seals and gerator gears and putting it back together stock... maybe there is another option out there?
cheers
Andy
Sydney