tear down

Christmas Day in Salem and of course at the shop!
I currently own a 1998 XJR 308. I have the engine out, see pics. I want to only do this once and do it right. I have it torn down to the heads which are being machined along with the valve job and cam's and caps. My question is there a somewhat inexpensive mod on the cams to increase performance. I have located a source for injectors, and was also curious about the Eaton Supercharger and what types of mods are available from a trustworthy source and if anyone with experience has a point of view regarding value and performance and durability vs. stock. I do push this car at times and also will be upgrading braking as high speeds also require good stopping power I haven't located anything in the Brembo line as I know their performance is outstanding. Anything helps.

 

For Brembo brakes, Jaguar actually produced a set for these cars, the R1 optioned cars have bolt on Brembo calipers, the S type have a similar system but the calipers need brackets.

https://www.ebay.com/sch/i.html?_fro...rembo&_sacat=0

For performance upgrades - it's limited. If you want a serious bump in performance talk to member Avos, he produced a twin screw kit with Kenne Bell units, no longer does but may know of one for sale?

Obvious Pulley upgrades (smaller blower pulley, or larger crank pulley) along with an exhaust with high flow cats can give better low down performance.

Use the later 4.2 MLS gaskets when you assemble the engine.

Silicon hoses, a Maxbore throttle body, bigger diameter induction tube and filter housing all add to the marginal gains you can achieve, it's not huge leaps for little expense on these engines as they're pretty much maxed out from Jaguar.

 

Depending on the miles of your car, getting the heads milled, valves and seats machined along with the mls gaskets mentioned above and with proper valve clearance adjusted, power wise the car should be running pretty well.

I had 234K miles on my 98’ XJR about 3 years ago when I redone my heads. The amount of vacuum the engine produced was so low that the supercharger never even engaged. Today at 253K miles it’s still going strong.

Getting back to your car, I would maybe stay away from the K&N filter because the oil gets on the MAF sensor and throws codes.

As far as the supercharger is concerned, without knowing the miles, I’d get all the bearings, coupler and oil replaced while it’s off.

Replace every coolant hose seeing as its 21 years old now and you want to do it once like you said. Thoroughly flush out the heater core while the engine is out is easy also. Blow compressed air thru the fins of all the radiators to get 21 years of debris dislodged would be a good idea. Also I used Pam heavy duty oven cleaner inside both intercoolers and so much sludge came out that you could see the fins inside again.

Good luck!