Hi Avos,

How about the XJR x350 , do you have a kit for it? Can you email me eurofalcon@gmail.com

Thanks very much in advance

 

The 4.2 STR kit and 4.2 XJR kit is exactly the same.


There is one 4.2 STR and one 4.2 XJR running around actually.

 

Is there one for sale??

 

I mean do you have a kit for sale?

 

Almost, its pending some dyno results, if that is as expected I think I release the kit.

 

Ok great! Then please let me know.

 

Too bad these kits aren't available for the 95-97 inline 6 4.0ltr X300 XJR!

.

 

I had been off of the forum for a while as I built up an offroad Land Rover. I finally got the XKR back in action!

The problem turned out to be a switch under the J gate shifter. There was an old Technical Service Bulletin about the issue that had never been addressed. As that was dealt with, I had Falconworks install a monstrously huge fuel pump into the driver's side front fenderwell to act as a 'supercharger' for the existing fuel pumps. Since I'm running a smaller pulley, the car needed even more fuel delivery. Perfect!

Guys, this supercharger kit makes your car C-R-A-Z-Y fast. I hammer on this thing every time that I drive it. Now, it's time to go get some new back tires (the front ones are still like new).







The distraction that has kept me busy:

 

Nice! Please dyno the XKR soon!!!

 

Quick question.

What is everyone doing for the transmissions on these cars?
The specs on these from ZF are very tight? rated for 408 HP?

I have a quaiffe limited helical, but I'm very curious to know what folks are doing for the transmissions to handle the extra power, and who's doing the work?

any recommendations?

Thanks!

Joe

 

There is already a discussion about the 6HP transmissions in another thread ==>> https://www.jaguarforums.com/forum/s...-power-139688/ I suggest you take up the topic there.

Let's try to keep this thread on-topic.

 

The link is a good place to go for the upgrade options but the 6hp26 is pretty tough. I haven't done anything to mine after the twin screw was installed and have not seen any change it its behavior.

 

Hello avos,

i also like to know how much a kit for my 2003 XKR is, i have send you a mail. If you have a idea for the air intake the german TÜV will not kill me i am thankful also.

 

I may have some very good news for 4.2 STR and 4.2 XJR owners who like a little more power as I just received dyno results.

They look absolutely great, will to study them carefully as I wasn't there and it was on a dynapack one which I am not familiarwith.

I could only find one post with some dynapack results on a STR from GT42R
https://www.jaguarforums.com/forum/s...on-str-104033/

Roughly 311 rwhp in stock trim.

Will post the dynos later today or tomorrow, but keep the number above already in mind...

 

Very exciting news!!!

Been thinking of buying a X350 or even X358 to do the twin screw conversion on, and let the STR go...

 

Hi All I'm the one with the XJR T/S kit

First may i apologize for the wait for this kit as i feel i may be the one that has made this kit a year late
Avos started the install in April 2013 , and all was going well ( various trips back and forth from the UK to Avos )until in February 2014 when wile out doing a WOT run for Avos the engine went bang , what had happened was that i broke cam follower shim, so what to do? , well i contacted Tom Lenthall ( photos and dyno resultshttps://www.facebook.com/TomLenthallLtd )who made my car happy again.
Lucky for me Tom and Avos have known each other for many years, so between them i knew my car would be top dollar when done
What i can say is as a feel in the pants feeling , the car is now able of warp drive
If you have read any of "Jeff in Tucson " comments about the power of this T/S type set then that's it , but can you imagine this big old jag sitting at the lights and then boom he's gone , I tell you the big grin i seem to have gained is going to be hard to shift

Its been a long road but now its done its been well worth the wait , and I'm sure all who have this kit will agree , that said its nice at the moment to think i properly have the fastest road going X350 XJR on the planet ( don't suppose it will last long though)

 

Thanks for the kind words Davey, I have really appreciated your attitude, patience (that must have been hard) and enthusiasm, so am really pleased all is sorted now especially with these great results, and that you have now possibly the most powerful 4.2 XJR on the planet




Attached is a graph of the dyno result which shows a best run of 529 rwhp (and an older one with a bigger upper pulley and stock airbox).

Davey had 337 rwhp on the same dyno a couple of years back in stock form, so that's a healthy increase of about 192 rwhp. I need some time to interpret the values (as this dyno type is new for me), but considering the 311 rwhp from GT42R on a similar dyno and the 337 rwhp baseline, 529 rwhp is a pretty good jump, so the "pants feeling" might be very substantiated ;-)

 

What size throttlebody, and how much boost was this XJR dyno'd at?

List of other mdos on this XJR? (exhaust, fuel system, etc)

 

The Kit (next to the Twin-Screw and parts) consists of 530cc Injectors, a bored out TB to 82.5mm, 89mm intake piping, a 89mm MAF and large cone filter.
In this setup, so with the 529 rwhp run the boost was about 20 to 21 psi.

Al I know as extra mods are the sport cats and exhaust.

And all without a ECU Tune


PS I see now that I posted a picture of just 503 rwhp, I only have a vague video of the 529 one of which I can't make a clear picture.

@Davey, do you have a clear picture of the 529 rwhp run?

 

I would like to see the car running on DynoJet also to compare with some other numbers we have seen with TS cars.


Differences between dyno #'s: Dynojet, Dynapack, Mustang.