>After checking on some XJ40, now I have noticed a pair of Series III, on
>a very nice shape (although maybe a little expensive). But my question is:
>
>Do those cars, made on the middle 80's accept unleaded petrol?
Yes. All XK-engined Jaguars have aluminium cylinder heads with
hardened valve seat inserts and are perfectly happy on unleaded from a
valve-recession point of view, although quite a few Jaguar specialists
who should know better will sell you an unleaded cylinder head
conversion.
Where you run into problems is with octane rating. The XK needs all
the octane it can get and to run on everyday unleaded you will have to
retard the ingnition quite a long way, which can lead to overheating -
the last thing you want with an iron block, ally head engine ;-(>.
Best bet is to queue up with the Impreza WRX boys for a tankful of
Shell Optimax.
David Betts (davidb@motorsport.org.uk)
The Classic Car Gallery: http://www.ofoto.com/I.jsp?m=17830847103&n=398038677
Martin and Mellisa Rimmer - 17 Jul 2004 17:03 GMT
I run my on premium unleaded and BP ultimate 98 octane, always on country
runs and no dramas. had platinum plugs but the crap fuel in Oz burned them
out in less than 20,000 km. Gone to a hotter Y shape plug.
I'll see how they go.
Cheers
> >After checking on some XJ40, now I have noticed a pair of Series III, on
> >a very nice shape (although maybe a little expensive). But my question is:
[quoted text clipped - 17 lines]
> David Betts (davidb@motorsport.org.uk)
> The Classic Car Gallery: http://www.ofoto.com/I.jsp?m=17830847103&n=398038677