Do any of you know that our camshafts are hollow, and our cylinder heads have Cosworth numbers on them, according to the guys at the machine shop?

With the valve angle we have, we could easily go up one to one point five, on our compression, without any valve interference? We would probably need to run over 100 octane, but I was intrigued, by what I found having an XJ8 head skinned, because of a plugged radiator issue, and had the cams X-rayed, to make sure they were ok to reuse.

The disassembly wasn't as bad as I thought. The critter is back together, after only 3 days, and runs like a Swiss watch. We got the radiator recored for $175. The owner, who bought wheels from me, and had me rebuild his 135,000 mile trans, must have spent a wad on Ebay, because while the engine was apart, we replaced all the tensioners and guides. It was real easy, with the radiator, condenser, and most of the front end removed.

I knew Jaguar had a connection with Cosworth on their race cars, because when the team was located In Valparaiso, Indiana 16 miles from me in the late 80s, I worked on all their Audi Turbo Quattros. I got to play in the Tom Walkinshaw Racing shop with them, when Tony Dowe wasn't doing some secret stuff, to their engines, or body work, and occasionally stayed so late, that I slept on their couch, and drove to work the next day. They used heads from Cosworth.

Does anyone sell higher compression pistons for our cars? Do they use higher compression pistons in Europe? The bottom end of our engines looks strong enough for some more compression, and a few more RPMs.

When I bought my 928 special, in 83 from the factory, higher compression was the chief difference, other than the reground cams, larger throttle box, intake hole, and reworked Wiesach suspension, that squatted the faster you went. I feel very safe in that car.......Just curious......Mike

 

Not heard of higher compression pistons but was aware of the hollow cams and conservative clearance. Some advice I got from XJR99 was that Cat Cams knows how to regrind the cams with a higher lift and longer duration. They have a US arm that I was thinking to give a call.

No idea about the Cosworth connection tough, that is an interesting tidbit.

 

When reading about the design and production of the X-100, Jaguar had Cosworth build the heads for their V-8's I believe every X-100 has Cosworth heads.

 

IIRC Cosworth was involved with the MKII head design.

 

I thought things looked familiar when I looked at it, compared to the Cosworth Indy engines from the 80s. I also had a Cosworth Vega, that I am ashamed to admit was mine, and only drove off the Dyno with 88 HP, using dual side draft carbs, and an insanely high rear gear. The highest rated Vega that day only spit out 90 HP. It was GM's joke on us all...

After reading about things, after the revelation at the machine shop,
it was said that Cosworth manufactured Jag heads, until 2010......Thanks for the input.....Mike