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My car is bone stock drivetrain wise, other than the Adamesh mid-pipes that have the X-pipe. It put down 434/454 yesterday on a Dynojet, at Pro Dyno in Fort Mill, SC. The HP # is spot on to the factory claimed 510 flywheel if you do a 12-14% driveline loss, but the torque # is way higher than the factory claimed 460 flywheel. if you do a 12% driveline loss on the 454 torque to the wheels, that would put me at around 510 flywheel torque. That just doesn't sound right. 50 up on the factory torque claim? The mid pipes with the X may be worth 0-5 horsepower on a good day, so that's not it. If Jag was going to underrate the power, wouldn't they underrate the HP and not the torque #, as that is all insurance co's understand. I'm pretty confused. I assume that it's not the dyno's calibration, as then the HP # would probably then be much higher than it is too, and it is spot on to the factory claims. This guy at Pro Dyno is very well-known and his equipment is top-notch and calibrated, and he felt that my car is making an honest 510 flywheel torque, based on the numbers in the attached graph. What have you guys seen on a basically stock motor for torque? Here is the video of the pull/pulls. Thanks.
Also, was the dyno operator sure about that 12% drive line loss? Generally we always used a higher percentage with automatics VS Manual and this number is closer to Manual drive line loss. Of course the hundreds of dyno runs I have made were not with a modern XK and were with much older transmissions, so maybe he has a better grasp on the newer XK trans drive line loss.
car has only 18,000 miles and is liquid silver too
12% would be minimum. it rages from 12-18, but if it was 18, i'd have even more flywheel torque (and HP), which would make even less sense!
whether it's 12 or 18%, the numbers for the torque are sky high.
i'm having a tune uploaded (stock upper pulley) and 200 cell down pipes both done soon, so it will be really interesting to see what numbers is then makes.
I have had mine dynoed recently and got similar results to you but as the torque figure was close to factory spec assumed that no conversion was necessary for that.
Stock mine was:
346kW = 463 bhp
614 N-m = 452 ft lb
After I flashed it with the XKR-S tune I got:
375kW = 502 bhp
674 N-m = 497 ft lb
Keen to see how your tune numbers compare. I still have to put on my smaller supercharger pulley but will do another dyno run after that.
I have had mine dynoed recently and got similar results to you but as the torque figure was close to factory spec assumed that no conversion was necessary for that.
You will hopefully be impressed although some say that you need the x-pipe to get the best out of the tune so it will be interesting to see what your numbers are compared to mine afterwards.
Or try one of the car tuners such as Velocity AP or others advertising on this site.
Everyone knows you can tune a piano, but you can't Tuna fish!
I've got nothing to add to the dyno conversation other than the car sounds terrific. Your old XKR back box is still terrorizing neighborhoods here in the Midwest, FWIW. Gracias!
You will hopefully be impressed although some say that you need the x-pipe to get the best out of the tune so it will be interesting to see what your numbers are compared to mine afterwards.
I have an X in the Adamesh mid-pipes, so i'm hoping for great results.
I will be flashing the actual XKRS tune, not a "version of". i'll fill you in on it soon. stay tuned....
That is exactly what I was hoping would be discussed, thank you!
If I eventually flash my ECU with a new tune, I would prefer it to be one that was developed by JLR engineers so I'm very interested to see how you go about doing this and the results that you achieve.
..... and the snarky comments spew forth.
Not a good way to make friends with the New Guy.
who made a snarky comment? definitely not me. i was letting him know it was the ACTUAL RS tune, and not a version of it from some tuner. i then told him to stay tuned (no pun intended) for more info. i did not see anyone make a snarky comment. just the opposite.
Surprising Dyno #'s for Almost Stock 2010 XKR
