Can anyone tell me what advantages/ disadvantages I would have if I swapped my standard 66 Mk1 GT diff and installed a 69 MK2 GT diff? I am assuming they are interchangeable. Thanks.
Life isn't complete until you have a pair of twin cams in the garage...
peteleo wrote:Larger the flange the ratio decreases.
Not with you there: the flange diameter has nothing to do with the ratio maintaining 1 to 1 from the gearbox, whatever its size. The ratio, and this is the important part, is dictated by the number of teeth on the crown wheel and pinion. With Fords it is generally etched into the edge of the crownwheel, e.g. 8/33 = 4.125:1. That's the bit which will alter performance, irrespective of the diff's coming from a MkI or MkII.
Driveshaft turning constant speed. Attached to larger flange 1/4 turn movement from point A to X moves a further distance than attached to smaller flange 1/4 movement from B to Y. Thus effecting differential ratio.
After doing some re-thinking on this Jim maybe right.
I'm looking at A and B being separate moving points but in reality it doesn't matter what size the outer diameter of the flange is.
I always thought that Ford made two different size flanges to alter the ratio a bit.
The larger diameter is to handle more power and torque. A 1/4 turn of the driveshaft = 1/4 turn of the pinion gear no matter the diameter of the flange.
peteleo wrote:After doing some re-thinking on this Jim maybe right.
I'm looking at A and B being separate moving points but in reality it doesn't matter what size the outer diameter of the flange is.
I always thought that Ford made two different size flanges to alter the ratio a bit.
That's it, Pete, you were possibly thinking linear motion rather than circular motion.