Hi
i own an x 300 4 litre manual jag
and I got this mad idea to studi if it is possible to upgrade it to an XJR
with swamping the whole engie or just the head with a supercharger
Have anyone tryed it
and had anyone experiance with the manual gearbox and clutch )is an ZF jewel that works great but I dont know if it is the same of the XJR)
Thanks
Simon

 

The supercharged engines had lower compression...not sure if that came from the head or the pistons. The block was different as well....beefed up in some way and a different bolt pattern at the rear of the block. Of course the fuel management is all unique to the supercharged model...ECU, injectors, MAF, throttle body, etc.

I think the XJR used a Getrag manual trans. Not sure.

Cheers
DD

 

Try here:

http://xjr6.co.uk/


One of the regular is an ex-Jag engineer who worked on XJR/6 development back in the day

Cheers
DD

 

Also, it's a GM trans, stiffer springs, shocks, larger brakes. The interior is different too. I think it would be easier to find an XJR.

 

I uinderstand the brakes and suspention discussion..but love the cream executive leather
I domt want to made it an xjr just to get more pepper in the engine bay

 

If you really want to go through with this.....I suggest find an XJR what needs work and buy the whole car. It wuld be alot cheaper. I bought an 96 with 47K that needs work for under $5k. You mainly need the engine, trans and supporting electronics. Or buy an XJR exchanged the interior and suspension (shocks and springs) on yours.

 

the problem is to find a manual gearshift xjr......
an auto does not interest me

my manual x300 is mostly so quick than a auto xjr
then the ciils and springs I prefer to mount KONI stuff
and for the brakes maybe EBC red stuff
in Europe hmmm 5000 usd means 3500 euros jes jou can find an good x40 or an xjr x 300 with melted eaton supercharger and in need for ar complete engine rebuild (around my country)
but thanks for the opinion
Simon

 

Good luck, let us know what you decide to do.

 

it is obscenely cost and labour prohibitive to convert your n/a X300 to a supercharged version,
it would involve pulling your motor, changing pistons&rings, as the lower compression I'm pretty sure comes from the rings&pistons, ECU, all kind of wiring madness, etc.

however,

the jag-lovers.org forum has much more information on what it would take to make the conversion; I'd run over there and do a search and see what comes up. would certainly be enlightening.





me personally, I'd go to the ends of the earth to preserve my manual tranny, so I get where you're coming from. :]

 

thanks and nice wheels

 

This is the same project i am soon taking on. I am waiting to get the crashed XJR delivered to my home where my XJ6 lays in wait for a full transformation inside and out. I was wondering if i would be able to use the same engine wiring harness.. hoping they used the same one and just pluged off the wiring or such that was attached or related to the supercharger.. seemingly i doubt it because it wouldnt be a project if it were that simple.. i know the ecu will be changed etc.. can i leave my rear end or would it be benificial to swap the rear diff and axle and suspension in one shot? I think i will do th fropnt end for sure.. i would assume the brakes are bigger and ould do some justice for the added power.. I was asking before about this swap and really havent had much response from it as of yet.. curious of any common issues or things to note prior to flipping drive train to sav myself some issues once it is bolted in..

 

This is a quote from JTIS: "The hypoid final drive assembly is available with either a conventional, or a limited slip differential.The limited slip, 'Power-Lok' unit may be identified by either a tag carrying the legend 'PL' or a label with an 'X', both to be found on the rear cover." I'm guessing the R has the LSP, but check out the label to figure which you want to use.

 

I don't know for sure but I'll bet the engine harness will be different due to the difference in component locations on the supercharged engine.




A full swap-out would be the easiest way to get the limited slip diff, and the XJR springs, shocks, and rear anti-roll bar




On the 6-cylinder XJRs the brakes were the same as the standard XJ6. You'll want the XJR springs, shocks, and anti-roll bar, though.




Well, you may be the lone pioneer in this case. What you're suggesting is a huge amount of work....more than most would undertake. Many guys would just go out and buy an XJR.


Since you'll have a donor car alongside, with every part you'll need, I don't think there will be issues....other than the enormity of the job itself.

My hat's off to you for your enthusiasm

Cheers
DD

 

Thanks for all the info Doug! much apreciated....I personally dont see it being a huge project as everything i need is going to be side by side in my driveway and i will have the xj6 to learn where everything is to take it out.. then again to take it out of the xjr.. that makes putting it all in so much simpler to bolt it into the xj6 when you have removed the parts twice before y9ou put one in.. the interior should be a days work.. maybe 2.. (full swap less carpet) and the drive train.. and yes will do the springs and shocks.. but may just buy high end shocks and springs and put them on my xj6 instead of stock xjr ones

 

I'm pretty sure the R brakes are bigger than the base model. I replaced my fronts and they are the same as the XJS. Truthfully, I think Jag gave the wrong specs on these cars for front brakes. The first set I got didn't fit and I had to return them. I sat in the auto parts store for 2 hrs. with the owner trying to figure out what brakes fit the car. We found out some how everyone has the wrong specs for front rotors and pads. We looked at 3 different manufactures and they where all wrong. It wasn't even the correct bolt pattern.

 

Not that mine is the final word....but I don't think so. :-)

Not sure about *aftermarket* parts listings but none of my *Jaguar* part catalogs seem to differentiate between XJ6-XJ12-XJR with respect to brakes rotors, pads, etc. on the X300 cars.

I think it was starting with the X308 cars that the XJRs got uprated brakes.

I'll do s'more checking....

Cheers
DD