I have a 1998 jaguar XJ8L and i want to put a supercharger on it what do i have to and not to do. thanks jon

 

Hi Jon, welcome to the Jaguar Forums, we'd greatly appreciate it if you'd introduce yourself and your car in the New Member Area... https://www.jaguarforums.com/forum/n...-intro-must-5/ ...top left task bar under Forums, ...General Jaguar Forums, ...New Members Area

I am really sure this is a job you'll not want to take on. To start, purchasing the equipment would be pricey, the SC model has 2 fuel pumps for when you get on it and that's not the only thing, it gets rather deep after that. None of your ECU components will work with the SC, so another ECU will be needed and flashing it to match will be costly. I'm sure some others will verify this with some other costs to help steer you in a more cost effective direction. You'd save yourself a whole lot of time, money and aggravation by purchasing one already SC'd. Go up into The Marketplace...again top task bar, 4th from the left and do a little shopping from members. There are many SC'd models outside of the Marketplace also and at reasonable pricing.

 

Lift the XJ8 up on a lift and drop it on top of an XJR!!!!!!!!!!!!!

Problem solved!!!!!!!!!!!

bob

 

Manifold pressure has nothing to do with compression ratio. Whether it is a blower or a turbo. Pistons may have to be exchanged because piston heads will be much hotter and you may blow a hole in them when overcharching, MAHLE sells pistons for that application.

T.

 

To answer your question contained in the title of your post - yes, you have to lower the compression. The SC engines have different (lower top) pistons; the cylinder heads are the same for SC and NA. I do not know whether there are extra oil squirters in SC blocks.

 

no manifold pressure does not have anything to do with "static" compression but everything to do with cylinder pressure when sc or turbo. And even cam profiles, and timing have a major effect on this too. You can blow a hole from high cylinder pressure which is why you want to lower comrpession, retard timing under boost, use stronger than stock internalls but this depends on boost. Your killers are lean afrs(burnes holes in pistons) and detonation from insufficient fuel octane, too much timing, too much boost, too high static compression, engine and cylinder head design. Best bet is exactly what bob(motorcar man) said. Get a xjr. You will be $1000's ahead. There are soooo may things to be done it is a big under taking and expense. But yes can be done with time and money. But i would not ever recommend doing it to a na engined car when there are sc cars of the same model avail. I did this to my nissan frontier which entail a ken bell sc from a corvette ls engine, bigger fuel pump, 1000cc injector up from the 385cc stock. Billet rods, studded motor and forged custome pistons. Custom welded and machine intake, pulleys and custom ecu tuning to run it all. The end result is a v6 engine that went from 265hp stock to 475hp at 12.5psi boost @7000rpm. But this vehicle never came with a sc. And Im sure I am well over 10k in money for this upgrade. Still a drop in the bucket compared to a couple other cars er truck I have in the garage that I have owned for 25 and 35 years.

 

Not sure about the x308's, but the x350 XJR's had oil squirters I'm pretty sure.

On the thread at hand, don't forget once you do all that you will want to replace the transmission with one from an XJR as well.

Most of the engine-related info you could want will be here: http://jagrepair.com/images/AutoRepa...Code%20168.pdf

 

Sell your XJ8 and buy an XJR.

 

There are supercharged VDP's floating around for sale.