Now that the engine is out of the car I could properly inspect my transmission. It's working good enough for me, unfortunately for me it isn't original. It's a Borg Warner 66 and my engine is a 4.2 from early 1969.

So, instead of being sad because my transmission isn't original, I'm curious how fast my car should go with this transmission?

Engine should have 245bhp and top speed for early 1969 is 170kmh. Top speed for a car from 1984 with the Borg 66 fitted is around 185kmh with only 170bhp.

Europe, I suspect it's a car from Italy.

Source:
1984 Jaguar XJ6 Series III full range specs
1969 Jaguar XJ6 Series I full range specs

 

The BORG don't care as to HP input. That is to top speed. It is the ratio in the differential. A car fitted with the 2.88 is faster than one fitted with a 3.54. In theory, that is. Other factors involved. Including the torque to "pull" a high ratio rear.


245 vs 170 is the key or is it? Real numbers? Sale numbers ?


I doubt that you will see any difference in performance attributable to the BORG 66.


Basic old design, but tough if maintained.


Carl

 

Thank you Carl. Might take out the rear suspension next year, when I´m done with this. The engine will be replaced with a freshly rebuilt engine, brand new +0.20 pistons but crankshaft is RIP so mine has to go in there. Find a series 3 head, replace timing gear, studs, core plug and some other stuff to top it all off and I'm hoping to be done for years so I can buy another Jag and start all over

 

Well........ Merry Christmas

 

245 was the rating under the old "SAE Gross" system . 170 was the rating (for the low compression 4.2) under the "SAE Net" system....which was close to the DIN rating system.

Cheers
DD

 

What about the 1982 XJ12? 170 horsepower is useless, I need more.

 

Supercharge !!!!!!

 

A 1982 V12 would be the "HE" version. Those are rated at [something like] 299 SAE Net horsepower for the high compression version and 262 SAE Net for the low compression version


Cheers
DD