Deferential Posi parts U.S

[cal44]

U.S and Canada guys. We have a Plus2 with everything stripped out of the back except the differential, body is still on. I was thinking why not put a posi in it and something around a 3.25 ring and pinion. I farm out this type of work. If I do some homework first then it will save the tech some time shopping the parts.
A hobby car without posi is like .........well, it ain't right.

A) What do you think about the the ratio? To high?
B) Who are the suppliers for the parts?

Regards,
mike

[vernon.taylor]

What's a 'posi' ?

@+

Vernon

[StressCraxx]

"Posi' is a nickname for Pos-a-Traction" GM trade name for limited slip differentials.

Contact Jay at JAE, Dave Bean, or RD Enterprises for availability. The two most popular are the Salisbury type and the Quaife.

[cal44]

Since I am a Ford guy I could have mentioned traction lok.........but posi is well recognized here in the states as "the term".

Thanks brother Craxx

mike

[rgh0]

You will struggle to find a 3.25 diff ratio unless you custom make it yourself. The lowest commercial ratio I am aware off is 3.54 that Ford made for Escorts or 3.55 that was made for Lotus.

This 3.5x ratios are great for cruising especially if you have a 5 speed Lotus or Ford box on modern motorways which have relatively low first gears to overcome the high diff ratio for starting. If you made a 3.25 then you may struggle with a 4 speed box on hills in first gear in a plus 2 with the especially the close ratio or even the semi close standard 4 speed box.

The Quaiffe diff is far better than the alternative designs in the relatively light Lotus. In reality a plus 2 on the road does not need it unless you are putting a 150+ HP engine into it or stiffening it up a lots as the relatively soft rear suspension ensure good traction on both rear wheels in almost all road circumstances.

cheers
Rohan

[cal44]

Thank for insight Rohan.

mike