The local community college had a dyno day today....I originally went to just watch everyone but I decided to put the XKR on.

78°F
40% humidity
92 octane (10% ethanol)

Anyway it's a 2010 XKR, and as far as performance mods go it has

Pulley
ETG tune from when I bought the car 3 years ago
Exhaust built by me
Modified stock Cats by me
Intake by me
And the Bosch intercooler pump

Results were 528 rwhp 535rwtq

 

 

https://youtu.be/nHmOM3hq5ZY

 

Modified cats - please explain more & exhaust built by you is that just the mid-pipe section would love to see some pics

 

Guessing that Chevelle had some mods too!

 

Nice, your car must move! Those 5.0 SC engines are something special with a few modifications.

 

The rear portion of the cats were removed...and the exhaust is 2.5" SS, smooth bends with X pipe that I custom built. Then I modified the stock rear box to bigger (2.5") inlets and outlets and deleted the valves. I'm pretty sure there are pics somewhere on this forum

 

LOL, yeah he had a little bit of work done....and it sounded awesome!

 

Thanks! I think it does pretty good, it's got 65,000 miles on it now and alot of guys on the forums act like that is high miles....I drive mine everywhere!

 

You have lost power on the lowend. One of Jaguars claims to fame with the 5.0sc is it develops 85% of torque by 3000 RPM. Larger pipes will do that! And the removal of resonators on the intake.

 

What happened to all the low end torque? His graph shows it peaking at 4500 but falls off sharp below that. Mine shows it coming in full at 2500 and staying flat all the way up. I heard that the more you open up the exhaust the more power you make but at the expense of the low end. If you had a boost gauge you would see the boost pressure drop from the freer flowing exhaust. You would need to put an even smaller pulley on to build the boost back up again.

 

They werent even getting into the throttle until way past 3k to keep the car from downshifting a gear

 

did you have any warning lights come on?

 

Pulled fuse 20 beforehand, so had all sorts of warnings. Abs, dsc, e-diff, no dynamic mode

 

I had the same warning lights after my dyno but I didnt pull any fuses. The lights cleared themselves after driving around for awhile.

 

Yeah I'd like to do it again only trying it with the dsc off leaving the fuse in. After I put the fuse back in it still had the faults, after one more restart they all cleared.

 

What does fuse 20 do? How did they do the dyno with dsc on? My guy tried it and immediately said the dsc had to be completely off do to the pull. Holding down the button for 15 seconds does that

 

Nice!

 

Fuse 20 disables abs, dcs, and dynamic mode evidently. The dyno was not done with dsc on, because fuse 20 was pulled.

 

How's reliability been with the mods? My next car will probably be a XFR with the same 5.0 SC'd engine and knowing myself I'll most likely want more power.

65k is nothing for these engines, I've seen a XFR with over 145k driving without any issues. We buy them to enjoy them so why not!