How does the XK6 engine block relate to the AJ6? Is it possible to bolt the AJ6 engine into a Series 3 (XK) car? What about the AJ16? It seems like a newer inline 6 would be a fantastic upgrade for a Series 3 as opposed to a Chevy small block. Has anyone seen this done?

 

I've heard of several guys putting an AJ6 into a Ser III XJ6. There are some pictures out there someone on the www. In a very brief nutshell the basic bolt-up is fairly painless but it's takes lots of time to work out the detials: exhaust, throttle, cooling, etc. The end result is supposed to be very good.

An Aj16 might be trickier only because of the electrical architecture and engine management stuff

Cheers
DD

 

These AJ series engines are very, very, good, probably as reliable as the Chevrolet engine, and of course, keeps the Jaguar a Jaguar. The AJ16 is probably the best of the lot, but there will be less around as they were not made for very long before the AJV8 came out.

 

With the way the rocker arms break off the studs on the L05 Small block Chevys (Mopar RB engines don't do this as they have a proper shaft) and the way that the rear cam lobes can wear round on 70-80s Big block chevys I would definately rate the AJ16 as far more durable.

 

We have an '87 4.2L XJ6 and a '96 XJS with the upgraded 4.0L AJ6 (aka AJ16) and we enjoy both of them. The XJS runs like a top, although both cars are meant to be touring cars as the 0-60 times are not impressive. The AJ16 has about 40 more horsepower than the 4.2L. The Series III is a couple of hundred pounds heavier than the XJS, though, so the additional horserpower will be negated. The electrical components on the two cars are quite different. I would think an engine swap would certainly require a major electrical upgrade.