I have a 1970 E type with improved breathing and a 3:54 differential. I have more or less resigned myself to replacing the current 4 speed with a 5 speed for fewer revs at interstate cruising speed. I had considered just replacing the differential with a 3:07 and keeping the 4 speed, but the additional gear is more appealing. I would appreciate some helpful advice on the best differential gear ratio to complement the 5 speed.
Submitted by gweaver@oakholm.com on Mon, 08/24/2009 - 01:19
Submitted by Myobb@freenet.de on Sat, 08/15/2009 - 14:44
Ideal 5 speed transmission/differential ratio combination
As recorded in my posting of July 23rd, 2009 I have a Classic Jaguar 5 speed box. Retaining a 3.54 differential (good for acceleration) I have the following ratios (which I think are standard on CJ boxes):
1 2.95
2 1.94
3 1.34
4 1.00
5 0.77
They work OK. However as indicated in the aforementioned posting I am not a fan of 5 speed boxes!
Submitted by mfrank@westnet.com on Mon, 08/03/2009 - 22:59
Ideal 5 speed transmission/differential ratio combination
I have a JT5 w/.80 overdrive. Rear end is a stock 3.54. I think the combination is perfect for regular road use.
Many thanks to both of you. Your responses and the earlier one referenced are very helpful.