Which is the better purchase - 1990 XJ40 or 1994 XJ81?

[Ballard]

The figures suggest the V12 should feel more powerful but in reality when I've driven them they don't feel like they had much more torque or power. This is, of course, a subjective observation.

The V12 does feel considerably more special and characterful, however. It is a very charming engine and charm counts for a lot. Afterall, if charm did not matter I would buy a Toyota Corolla.

[naki_k]

Quite a few of the V12s out there are not well maintained. Old Ignition parts being the main culprit.
So if you have driven a 12 and it didn’t feel much more powerful than a 6cyl, it’s quite likely not running on all cylinders. I have been to see plenty of V12s where the sellers claimed it’s “running perfectly, very smooth”.
I get there and it sounds more like 9 cylinders at best, and obviously misfiring.
The 12 feels way more torquey than the 6 IMO, when it’s running correctly!

[naki_k]

I don’t think anyone would consider a V12 a daily driver though. Hence why I asked how you intend to use the car.
It would be a weekend toy/ show car. Even in the US with your cheap fuel?

[ChrisW]

If its a choice between a 30000 mile XJ81 in Moroccan red/magnolia or a 97000 mile blue/grey XJ40, all else being equal in terms of overall condition, then I'd suggest the lower mileage car in what is currently a desirable colour scheme would be a better investment. However that could change if when you view it, that particular car exhibits mechanical/electrical and bodywork issues despite the low mileage!