If you need a reason to take a drive here is one

XK
1

I am interested to compare the affect of tires used today-and pressure used, wheel, and differential ratio to: actual rpm at 4th gear speeds of 50, 60, 70 mph. And compare to the old road tests and factory spec info…SO…on a drive…if you could have your passenger note the rpm at each speed in 4th (not Ovr-drive) , (it may be of interest to you to compare a gps speed to your speedometer.). Let me know the rpm at each speed…and also what tire your are running, your air press, and your diff axle ratio. I will make a chart…and share it.

For Example: 50 mph 2350rpm: 60 mph 2800rpm; 70mph 3210rpm with 3.77diff, Michelin Pilote X @32psi on 5inch wide wire wheel. (or a 5.5inch disc, or a 6 inch wide wire)
Nick

2

zzzzzzzz zzzzzzzzzzzzzzz zzzzzzzzzzzzzzzz zzzzzzzzzz
anyone driving? rpm at 50, 60, 70…with your diff ratio and tires?
Thanks…Nick

3

I will do it when I can persuade my wife (or someone) to take a ride with me in the 120… :laughing:

4

Hi Nick,

Sorry, I have lots of data, but no XK. :slight_smile:

A series 1 E-type 2+2 auto-> manual +O/D conversion 3.31 final drive.

Michelin XVS 185VR15 OD engaged 100km/h 2.000rpm. 200km/h at 4.000rpm.

A factory original manual + O/D XJ6C with 3.54 final drive.

Dunlop SP Aquajets 205ER70 O/D engaged 180km/h at 4.000rpm.

A factory original series 3 V12 E-type manual with a 3,31 final drive.

Michelin XVX 205VR15 229km/h at 5.800rpm.

Mark V 3 1/2 Litre Drophead, not perfectly sure about the final drive but I think 4.09 or 4.07ish,

Pirelli Cinturato 6.50x16 120km/h at 3.600rpm.

Cheers!

5

thanks Pekka: now go find that perfect XK120 to buy and drive !!
Nick