I’ve only had this 2012 XJ SC for 6 weeks, but already managed to get all of items sorted out. I had the SC snout rattle so got a rebuilt unit with smaller pulley. Got a tune from Velocity AP (great turnaround and service).

Went to my buddy’s shop and hit the dyno. Redline was my best pull with just pulley, which was stronger than I expected. Blue line was with tune. Each dyno is a little different, but definitely huge improvements, especially in the midrange, and approaching 600hp.




It was raining today, so didn’t really get a good chance to check out the butt dyno afterwards. Got some minor fixes to do and then maybe replace front resonators with X-pipe for some improved growl. My first Jag and absolutely love it.

 

Thanks for the post we don't get enough real world data on these cars. So dyno runs are pretty rare.
.
.
.

 

It took a bit to figure out how to dyno it. Couldn’t get to the ignition coil easily. Had to hold the traction control button for 10 seconds to fully disable it. Then slowly get to 4th gear and 2500rpm. Even then it was tough to really hammer it with sport and dynamic mode on. We managed to get 4 pulls before it got major heat soak. Took a while with some snail fans to get it cooled down enough for the post tune runs. Likely another 10-20hp available with some cooler temps. Still worth it to get some good before and after. Wish I had a before pulley log but oh well. I’m still suspicious that it gained 60hp from the pulley when they are rated for 30hp gain. But even if I discount the final run by 30hp, it still ends up about XJR575 territory. Not bad for $1000 🤘😎🤘

 

Good numbers, glad to see more dyno numbers.
What gear did you do your runs in?
Did you install the upper and lower pulley or just the upper?
You have any plans to visit a local dragway?

 

We ran it in 4th per recommendation. I only did the upper pulley. It was minimal to add it from the supercharger rebuilder. Chris @ VAP said they only recommend one or the other but not both for the Denso. It’s missing a reading the Bosch has that it needs. Plus I didn’t want to push an older engine that much.

As for the track, I’ll see if I can get out to one. Never really been to one by us. Any recommendations? Perhaps Rockingham? Otherwise, my Bluetooth OBD2 I just got has a “performance” widget that may produce some decent results on an empty street.

 

Yeah Rockingham and zMax in Concord are the closest 1/4 tracks. Everything else around the Charlotte area are 1/8 mile tracks.
There is always the Dragy, people swear by them.
You can search the F-Type section for more info on it.