OK, first off I looked at every thread in this forum...I have learned from reading the 1.5 pulley seems the way to go for me...Sounds like the 3 lb would work the best in cold climates plus I don't want to get involved with machining the snout...Sooo I have not seen anyone here with hard results such as dyno sheets from the same day and approximate temperature...I have also read a couple of members stating they could not tell any difference and some did see improvement. (placebo?) Anyways can someone chime in and let me know your thoughts on this dodgy subject? Like to hear from members that have done the 1.5 pulley especially...Thanks

 

i done mine a bit over a year ago on my STR . powerhouse 1.5.
it defiantly made a difference !!! the eaton screams louder .also
mainly to the bottom end and mid range torque . but nothing to speak of at top end .
it pulls through the gears a bit quicker . and raised the boost 13.5 to 14.9psi so almost the 1.5 increase as claimed . it might only make 1/4 of a sec down the quarter mile though .
so value is questionable . the sound however is great.

 

I put a 1.5lb pulley on my STR about 3 years ago. If you're looking for a night and day improvement this isn't going to give it. In my opinion it was a very small gain which you would only notice if you knew your car very well. There was a bit more lower end torque and slightly more whine at WOT which I liked, but it seemed to heat soak faster. There's an old thread where a member who put one on his STR and gained 16rwhp and about 20 ft/lb of torque, but it was 20 degrees cooler: https://www.jaguarforums.com/forum/s...-thread-79842/

It's also worth mentioning the member who ran 12.9 at 109mph in his STR did so using the 1.5lb pulley and said his trap speeds were down after putting on the 3lb pulley so avoid that one.

Would I do it again when I put my Eaton back on? Probably not as the only mod I saw a night and day power difference on my STR was from replacing the Eaton with a 1.7 Autorotor (old Kenne Bell twin screw). Id say to go down that route rather than messing with pulleys as there was improvement on all boards and it's much harder to heat soak. It is a louder/higher pitched whine than the standard Eaton though.

 

i like the sound of this louder/higher pitched whine you speak of .
cool.
your points are correct heat soak is increased with ether pulley up grade .
and its not huge gains at all for power . but there is a gain to be had . all be it only at wide open throttle . heat soak can be dealt with too. mines good now with the 4liter capacity tank and 010 I/C pump .
and at $300nzd for 16-20HP and some extra torques is acutely a good dollar per HP gain .
and possibly the most noticeable gain that you can get from any one mod ,
within any of the very few mods available maybe excluding NOS & TS .
for most people a twin screw up grade is out of reach . financially or other wise.
i will say this , with the j pipe , x pipe , free flow cats and big bore pipes . the 1.5 pulley is the cheery on top and makes it all come together . for both sound and performance .
within the realms of the capabilities of the eaton roots blower. which is quite ok.
it makes a very eager/happy aj-v8 . i imagine all that with a tune , then the tune would become the new cheery on top .
I'm sure the TS is the ultimate upgrade but if you do the no#s the TS is very close to the same dollar to hp ratio or even/actully dearer .

 

Whatever happened to the remap of the ECU that Cambo was working on?

 

i think its still in production / testing phase . for the old 32bit cars .
i think the version for the later cars is on offer ? seen a couple of x358 and x150 owners claiming to have it .

 

Each series of vehicle has a different PCM, has a different tune...

X356/X358 XJR and X206 S-Type R is done.
X150 4.2L XKR and X250 XF SV8 is done.

X350 XJR, X202 S-Type R... well in a way it's done, but TBH it's not as thrilling as the results on the other cars.

This is not because of the tune, but of the limitations of the engine itself, and the PCM...

You might have seen I did some more testing tonight, ran a 12.93 @ 107.1mph in my XJR, which is awesome, the fastest ever.

But it's still not HUGE gains like we got from the X150 XKR...

I have one more card up my sleeve for testing next week.

 

Well done!
Could you provide the link where that gain on the XK150 is described (or say a bit more about it)?

 

I have the smaller pulley and on a run just now the maximum boost I get ,according to Torque pro, is 14.75 psi.

Having said that this is the best run I have had since installing the Quaife.

Wheels spin extremely easily even from a rolling start but no "weird" sliding which is what I would describe the feeling as prior to the LSD. Gears change at the red line and I hit 90 very quickly on my back roads and I have to brake to bring the speed down to more reasonable speed.

 

It's not bad is it!? It could probably use some high flow cats to give her a bit more growl though. It's a shame I'm not upgrading to the 2.1KB.

 

Sure, here ==>> https://www.jaguarforums.com/forum/x...esults-177494/

Forget about trying to read boost with Torque, it's not possible.

The MAP sensor in these cars before 2006MY is located between the throttle body and the inlet of the supercharger. So it is only exposed to vacuum, not actual manifold boost pressure post-supercharger.

Yes you get some numbers from Torque, but they are not accurate.

 

what about Torque Pro vacuum reading? Also how can I measure boost?

 

Torque or Torque Pro, same thing. The location of the MAP sensor means you cannot measure boost. Torque has some offets and factors and stuff which means you can get a number on the screen that looks like boost, but it's not.

Easiest way to measure boost is to put a sensor or gauge into the rubber line that runs from the outlet of the supercharger to the fuel pressure sensor. Put a tee in there and then run the hose to your gauge/sensor.

 

Sounds nice mate , I recon it's actuly quieter than my eaton ,
Maybe a good thing I don't know ,
It is a real shame you are not going to the 2.1 upgrade , would have liked to hear about the results in comparison with the 1.7 .

 

Very nice work there , very nice to see you got your target , it does prove there is an improvement on stock tune .
Although it may be not as bigger gain as you hoped for , none the less it's a gain . I truly thought your trap speed would have stepped up a couple more mph .
Did you strip any weight for that run ? Or did the spair wheel do a 12.93 as well ? It must have done all the work off the line .great effort though well done .
Do let us know what your last card reveals , thanks

 

Cambo
I have an '07 XJR (VIN H16220)
Looking up your ref to "356", believe this is one?
Is your tune for this model's PCM now available?
Tks

 

Yes that's an X356.

Yes the tune is available, it's actually running in a couple of forum members XJR's, has been for a while now.

The only problem is, the tune can only be loaded to the car using the IDS or SDD diagnostic system, and I don't know anyone in your area who would have one.

 

Cambo - No worries!

Best wishes to you with your SC Jag tuning work. Do let me know if your PCM tune (for the X356) becomes available in the SE USA area. My own Jag scan tool is limited to Foxwell 510 with Jag/LR software, which I don't believe has the right capabilities

 

I'll see what I can do.

 

Great info guys! Thanks...Guess I am going to do it...From what I have seen cutting the old pulley of is the best way to remove it. What is the best method to install it?