Hello, I have had the car in question for over a year. I purchased it and am the third owner. I restored it, painted and replaced rusty parts, new interior, restored the wooden elements....etc. I had a problem with the engine, it wouldn't rev above 3000 rpm.I bought a donor with a 12 cylinder engine, it was cheap and the parts I needed for mine cost more than the entire donor.I replaced the ignition on my Jaguar with the one from the donor,, I transferred the ignition amplifier and both coils. The car flew, now I felt it running. Then I installed my original coil and it doesn't run again. Now I ordered an original one and am waiting for it. I have no idea what could be wrong with a coil, I will try.

 

I also had a problem with the differential, it was leaking after I paid for repairs at a service station...the differential started to howl and was left for repair sometime. The original one was 3.54 PL. I read on the forum topics about replacing the differential with a different gear ratio and decided to try it, I had a differential from the donor.I installed 2.88 PL...at least that's what it says. My car has a 5-speed manual transmission. Honestly, 1,2,3 gears are now usable and long, the acceleration has decreased significantly, as expected, and I have to drive mostly in 4th gear on country roads. For me, this replacement is not good.

 

2.88.1 is good for an auto trans as the torque converter supplies additional reduction.

3.5:1 is typically about as low as you want for a manual trans unless the manual trans has a ~3.5:1 or so 1st gear.

The general rule of thumb is 1st gear ratio x rear end ratio should be about 10:1 for reasonable acceleration and minimal clutch feathering on start out

Doug

 

A 2.88:1 is far too high a diff ratio for a 3.6. They were only fitted to auto trans V12 HE models, until the fracelift V12s had the 4 speed auto fitted, whereupon it was changed to a lower ratio.

 

That's right, you're right. 2.88 is not suitable for a 3.6 engine. Unfortunately, the 3.54 differential is still under repair, and I want to drive my car in the last good days. After they repair the 3.54, I will replace it.

 

Hi Alex, I’m curious…did you put the 2.88 differential unit into your car’s rear cage, or did you put the whole rear cage assembly from the V12 car into the 3.6? Sounds like you have done a lot of work on your car—maybe show up some photos? Do you see many old Jaguars in Bulgaria?

 

I installed the entire rear axle from the V12 on my Jaguar. I installed the entire axle because it was easier, at least for me, than removing the differential and reinstalling it. Honestly, I'm looking forward to having my 3.54 repaired and the transmission replaced, 2.88 is not suitable for a 2.6 engine with a manual transmission. The car is slower when starting, yes, the gears 1 to 3 are more usable in city conditions, but outside the city I often have to use 3rd gear on inclines. Unfortunately, I didn't take any pictures of this particular repair.