First I've heard of M112's warping....

Is it possible to run a clutch on the twinscrew? This is the mod I'm sold on - turbo's aren't viable because of packaging problems (exhaust). I've looked into it.

Andre, have you seen a Nissan Navarra radiator? It's an inch thick and twice the surface area of oem - it might need mounting at an angle on an XKR?

 

@Sean B
When I started I indeed looked into a clutch system, as that would have been an ideal situation. A clutch system is pretty big, and wouldn’t fit our application, and it would also add complexity and possibly durability issues. Now a couple of years further ahead, I can’t see the need for it actually anymore. It could help in reducing the fuel consumption of course. The system is now so much more efficient then when I started. On my car with my driving style it’s only 10% more, which for 220 bhp extra makes it even more fuel efficient than most super cars ;-)

I now use a radiator with a main core of 600mmx380mmx32mm and that gives about 60% more surface area then the stock one.

 

This is what helps me slow down a bit, 410mm discs & 6 piston Alcon calipers.

 

JgaXkr, your car never ceases to impress !!!

 

JX;

Sweet!!!!

I second Whitey's opinion.

And your car looks standard otherwise?

What size wheels are you running?

Now I have to check and see what size the 'standard' Brembos are on an '04 XKR.

I am reminded of a famous quote by Ettore Bugatti when asked about the tenuous nature of brakes on his cars:

" I make my cars to go not to stop".

Certainly doesn't apply to your car JX.....


Whitey;

How accurate is your Boost Gauge Nav/Gauges conversion?

Certainly looks useful for any Twin Screw Conversions.

Which raises a question about if boost gauges are reading input or output boost?

Pardon my 'legendary ignorance'......it is virtually unlimited.'

Would be a good measure of the difference in boost pre and post SC conversions.

cheers,

jj

 

The HKS CAMP video based gauge system uses what appear to me to be quite high quality components, although the accuracy is not formally rated. I would estimate it is +/- 5% or better. Boost pressure is monitored in the intake manifold (post-supercharger).

 

The standard Brembo discs are 355mm & will fit on certain 18" wheels. I use the BBS Perseus wheels in the cold weather with Michelin Pilot AS. In the summer I use Arden 20" sportline wheels, these require a 1/4 " wheel spacer in the front & Michelin Pilot Sport 2 tires.





If I have to ever replace the discs I will go with 400mm as the calipers are pushed out so close to the wheels. When I had the discs made I went with the biggest they could make.

 

JX;

Thanks....you had the discs made?!?!?!

That sounds very pricey.....will you also cross drill replacements for cooling?

I can't tell and don't know if those are double discs on the fronts there, same for the rears?.

With your Twin Screw top speeds those brakes must be getting super hot when you slow down....no warping issues from heavy high speed stops?


Whitey;

Thanks for the speedy info as always....

cheers,

jj

 

@Jam Warping? Alcons? No chance.

I run Alcon system with 355mm 3 piece rotors (disc, Ti bell, hats) They're fitted with Jaguar's 08' XKR-S pads, Ferodo. Best brakes made, better than AP Racing imho. A great help in fitting from Tony (XKRacer).

I've had fun outbraking friends 911's, XKR's and M3's easily - it's a 1.8t saloon.

@ Avos - did you have the rad made or is it adapted from another application? It's good to know they're no real fuel issue on your system and no need for a clutch.

 

The radiator was custom made. Not sure what size would fit an XJR though, but I think it could be about the same.

 

I like the slots, just having the holes makes it cheaper to make but an easy mod to do.....

I want to do something different on my next project, this car is going to be my car, so the majority of which will not be available, unless you wave enough $$$$ at me

Thought I would use an Aston bottom end, 4.2 heads with bored out combustion chambers to match the block and help me reduce the compression, I thought about using a couple of Rotrex superchargers, its all pie in the sky at the moment and I want a sequential box where the diff is.
I still just might stick a big Chevy in it!

 

I knew Racer and Avos would chime in on this.

My Daddy always said "You can solve any problem with enough time and money."

Thanks guys,

jj

 

@XKRacer.
You make me look sane again, thanks!

Now that’s a project, pretty cool, but to be honest if you go thru these lengths (and as I am not so religious) a twin screwed big chevy would calling ;-). Am just not a fan of rotrex, and just love instant power/torque.

 

I have to admit using a big chevy 7ltr with a supercharger sounds very enticing..... The idea of the Rotrex was mainly for there compact-ness... Idealy I would use a couple of smaller Kenne bells but fitting them in somewhere would be a nightmare, unless of course a did it mid engined...... Hmmmmmmm

 

I suggest you look for my post regarding Stiegemeier.

 

Stiegemeier ported the Eaton supercharger on my 2004 XKR as well as building a cooler on the front and working the throttle body. That was done after a reduced front pulley, cool air intake, Mina exhaust and Nameless cats.

I didn't dyno before and after and I'm not a track guy. My driving is for spirited pleasure on PA winding country roads so I can't give you numbers. But, before the XKR went to Stiegemeiger it had all of the acceleration and power I needed and could ever use. Now it's absolutely over the top and I spend more time taking my foot off of the gas than easing it down. 1/4 inch in pedal movement and the XKR is in pursuit mode. There is no where here to open it up with having a police encounter of the unfortunate kind. This spring it may journey to the raceway, just to see...

Other guys can argue the numbers but for acceleration at any speed , I'll put my heavy XKR up against all but the most elite supercars. And even if they out run me, I'm driving one of the most pleasurable and beautiful sports cars ever made. They can kiss my Cat ***.

 

I see ur in PA, where did u get the work done?

 

Mike, Don't know if you got my message. Dreamwerks Performance in West Middlesex, PA near Sharon does the work on my Jaguar. Josh is a German car specialist but he loves my XKR and would like it to be the meanest cat on earth.

 

Tell him that step 1 in making a mean machine is to ditch the Eaton, you can't go wrong with either a TS or Turbo setup. So what's the plan ?

 

Beware of Stiegemeier !! He doesn't know Jaguars at all. He knows Mustangs, which are a completely different animal. He made claims as to what he would do on my porting job and didn't complete half of what he claimed. Don't say you haven't been warned. Read my post on Stiegemeier for facts.