The work was done at ISP who I cannot recommend. I am not sure if I was the first Jaguar or not but had some damage to my car, a disconnected front impact sensor which cost me $175 at Jaguar dealer ship to find out, metal shavings in the engine room. They had huge problems installing the pulley. The shaft has to be heated up until it is hot red with a torch so when the pulley is pressed on it almost fuses with the shaft. it should not be shaved down.

I am not sure I have the AFR numbers in the files they gave me. I have another tuning tool now from Viezu for my XKRS on which i am installung a new manifold back Milltek exhaust and see if I can capture some AFR numbers there before we start tuning. The XKRS has lost all the overrun. I will definitely record them on the FType in January when I have the new exhaust installed and reflash the car. I have to look at the files at home to see if they include the AFR numbers or just hp and torque.

The power is undeniable though, the car pulls like crazy, it gained over 100hp at the wheel.

 

Those torque curves are more what I would have expected shape wise than some others that appeared on Pistonheads which look pretty badly heat soaked. I'm guessing the tweak at the end of the lower run was wheelspin?

 

Maybe the reason they had such huge problems is that the pulley needs to be heated, not the shaft. ASM in Hanover used a heating coil to heat the pulley to over 500 degF, and it slid on easily.

Do you still have your old pulley? I would be interested in measuring the pitch diameter of the OEM pulley from a V8.

 

Would heating the s/c input shaft have fried the shaft bearings. Discuss.

 

What!?!?!

Exactly. The pulley is an interference fit to the shaft, you heat the pulley which makes it expand & go a little soft, so it will slip over the cold shaft.

Heating the shaft is totally illogical, none of the pulley suppliers have ever instructed to do that.

I would say it's pretty likely.

 

+1.

 

No I do not.

 

my bad, the pulley has to be heated.

 

Ihoboy, I just had the ETG pulley and performance tune installed on my 5.0L and have the oem pulley. If you let me know how to measure the pitch diameter, I'd be happy to do so.

 

Outstanding!

Measure the diameter from the top of the ridges to the top of the ridges



Formerly lhoboy

 

d=65mm

 

Thank you!

OEM V8 pulley diameter = 65mm
OEM V6 pulley diameter = 62mm
Aftermarket pulley diameter = 60.5mm (smallest that can fit over shaft housing).

Results in a 7% reduction for the V8 and 2.5% reduction for the V6. Compare this to the 13-18% reduction pulleys we were installing on the R53 MINIs. Any significant power gain will have to come from the tune.

 

If I were measuring, I'd easily be off by 3mm or more trying to figure out where the top of the ridges are from the outside of the pulley.

Isn't it likely that they are the same size? I can't imagine why they'd go to all the trouble of stocking two different parts for such a small difference (1/8").

 

Foosh, I totally agree with you in theory. Was the measurement taken by just using g a tape measure and eyeballing or was any type of precision measuring device used?

 

I used two straight edges placed across the bottom and top of the pulley tracks. they were then lined up as parallel as possible and then measured at 65 mm. Yes, it was eye balled but it is extremely close to accurate.
BTW, I, regarding the installation of the performance pulleys, I learned there are 3 different manufacturer of superchargers that were outsourced for the F Type. On one of the suppliers, the housing where the pulley is has to be filled down in order to accept the smaller performance pulley. As luck would have it, mine has one such SC. It is minimal filling but it has to done to fit.

 

If that is indeed the case, which its probably not since only one brand of supercharger is used on the F type, you should file/drill out the pulley and not ruin the supercharger shaft by filing it. It's an interference fit and that's then end of it, if the shaft size is different you should adjust the pulley to compensate.

 

Please understand that I was not suggesting you weren't extremely close. My point was that 3mm is extremely close, particularly when you're trying to eyeball where the ridges start at the top and bottom and measuring with a straight-edge. I know the V6 and V8 superchargers are the same manufacturer, and I was under the impression that they both had the same model supercharger, but I don't know that for sure.

 

So far, of all the pulley swaps I'm aware of, all the SCs needed grinding or filing so the pulley wouldn't seize.

 

My understanding is that the SCs are the same, but the V6 is pumping more pressure with a smaller pulley. That's what I am trying to confirm with the measurements. I'm using a caliper gauge similar to the one above to measure the V6 and aftermarket pulleys.

 

Right, so you also need a caliper gauge on a V8 pulley to know for sure.