Well, before I flsh the car I figured I could get a baseline of the car to know where it is at to see the gains. I told Stuart I would do this before applying his tune so the XE guys can really see the truth in the gains to be had as Jaguar has detuned this motor for this application.

Overall it did okay but it wasn't was yas the car kept freaking out o the linked dyno but we managed to get a free clean runs before limp mode engaged.

All runs were made in 4th gear and it got a best of 290.4/259. The car was hot from the drive there but the weather was pretty cold at 44 degree.
I have the 20" wheels but don't think that matters as the rolling height is the same as those with the 19 or 18 wheels.

 

The HP seems on point, maybe even over the factory spec @ 20% drivetrain adjustment. But why is torque number so low? 259 @ 20% loss = 259x1.2=310lb/ft.

Do you think 20' rims have to do anything with it?

 

Limp mode was activated? Is your car OK? I know for the most part Dynos are safe if it's a good dyno and done correctly, but it still makes me nervous to watch It will be great to see the comparison after your tune. I thought Stuart's shop was in Canada? He must have affiliates in different states? Anyway looking forward to the results!
CRS

 

I think the TQ is low as we can't go WOT in 4th gear without it kicking down to 3rd gear so we have to wait until it gets over the kick down point to go WOT. Same thing happens with my XFR. The huge wheels may or may not play a part as I don't know the weight of mine vs the 18's or 19's.

Since this is a Linked dyno I don't know what causes the car to freak out but it locked up just like my XFR did. You get one good run and then the car kicks out of dynamic mode and paddles are disabled along with tons of other warning lights.

This is how I set the car up for Dyno runs, please correct me if I missed something: Enable Dynamic mode and turn autostart on/off to off. Then hold the Tract button until DSC is all the way off. Bring car up to 4th gear and about 3k rpms and then trigger the logger for the dyno and proceed to make a pull to redline or until it bumps the limiter. I go WOT one I get above the 3-4k rpm range to avoid it from kicking down to 3rd gear even though I am in manual mode along with S sport mode o the shifter.

Since no one has done the XE Dyno before and after for VAP I opted to do it for him and post the results so people know it is solid and real compared to many of the fakes out there. I won't go by a butt dyno ever after owning some of the high hp other cars I had in my stable. I need to see verification.

 

Not, too bad.

By comparison my S-Type 4.2 NA V8 pulled 250.06 whp / 259.67 torque.
================================================== =
You dreamed of a big star -
He played a mean guitar -
He loved to drive his Jaguar...

So welcome to the machine

 

Thanks BigCat09. Good results. How many miles did you have on the odometer when you made these runs?
(I'm waiting until my premature oil change at 3K, then I'll take my RWD 3.5 in for a run and post my results.)

Happy New year!

 

2,150 miles.

 

HI BigCat
When are you ECU tuning the car? Looking forward to your Dyno comparison:-)
CRS

 

I am away for work so I hope to do it soon as I return in few weeks. I need to flash the car and drive it a bit before strapping it back down to the rollers. I should have it done in 30 days or less if all goes well.

 

Please post revised dyno charts when you have the chance with the proper SAE correction factor applied so that results are compensated to a common standardized air temperature and barometric pressure.

Uncorrected numbers are not useful for comparison purposes. Hopefully your dyno shop saved all of the raw data from your runs and they can then apply the appropriate correction factors to put everything on a level playing field.

Are there exhaust fans at the rear of the car to make sure all exhaust fumes are pulled out of the building? Or just the single pusher fan at the front of the car and an open garage door at the rear?

 

I think he said my original plots so we can see the gains.
Just the front fan was used and the garage door was open, no other circulation is present.

I will look into the correction number but I plan to test in the same air/temps as prior.

 

It is almost impossible to replicate the conditions you tested in from one test to another. It is even possible that they change during a single dyno test, which is why most (good) dynos have built in "weather stations" that record the conditions for each individual dyno run automatically.

I'm an automotive engineer, we do a lot of dyno testing, there is a reason that auto manufacturers rely on engine dyno figures versus wheel dyno figures. You have far too many variables to account for, and keep consistent, in chassis dyno testing. Things like the hold down strap tension, tire pressure in the tires (effects the rolling radius of the wheel, as well as the contact patch of the rubber against the roller), even the bearing temperature at the axle of the dyno's rollers should be monitored and the dyno run only allowed to proceed when the bearing temp is within a specific operating window to insure that the friction losses at the roller's bearings are the same from test to test.

Too many shops splurge on a chassis dyno and drop in the ground and call it a day... without adequate understanding of the science of the tests they're trying to perform. And an even greater reality is that even if most of them wanted to test better, that they spent so much on their dyno, they can't afford the proper facilities and facility upgrades to use their dyno in the bare minimum of proper test conditions.

At the very least, make sure they apply SAE J607 correction to your previous and future dyno runs. Some people use SAE J1349, but for most of North America everyone uses J607 (because J607 has been in use longer and gives ever so slightly higher figures than J1349). Doing a before and after test on different days in different conditions (even if you try to make sure the temps are the same), will be meaningless without the correction factors applied. It is really unlikely you'll get the same air temp, with the same humidity and barometric pressure the next time you go.

 

Well, here is the update and the non-biased proof:

The gains are super impressive from just a re-flash. The car drives great also and I can't find any bugs with it at all. I want to put the crank pulley on next and see the numbers and the better low end grunt.

We faced the same issues as the first time but got it sorted out much faster this time. IT still seems to hold true that we only get 1 true good run before the car gets flaky and tosses faults.
I am calculating a 20% driveline loss and came up with about 450hp crank but I could be off by a tad.

 

You got some very serious gains there.

440hp and 420lb/ft @ 20% drivetrain loss.

~30% gain from the stock numbers. Amazing!

 

Hi Guys,

Great results and thank you for going out and doing this on your own, to verify the gains for other people.

A couple of notes - the drivetrain loss isn't 20%. You can show a rough estimation of the drivetrain loss by dividing your 'before' measurement against the manufacturer's stated output. Yes, totally possible that the stated output isn't correct etc. etc. but we're talking about some reasonably accurate figures here so assume it is making 340PS (335BHP.)

335.35/290.54 = 1.1542. So assuming the output originally is as Jaguar stated, you need to multiply your WHP result by that number to get the crank output.

1.1542 x 367.89 would put you right around 424BHP, for a gain of 89BHP. I would say that's a little higher than I might expect to see but it certainly shows our conservative estimate/quote of 416BHP based on the XF-S we developed on is achievable.

Either way, 77WHP and 103WTQ at $995 for our regular price is probably the least expensive HP you will find anywhere. At our current launch special pricing of $697 - on offer until January 31st... well....

 

The is very serious offer at $697 for that much power upgrade; very tempting.

 

And just think, I got mine on your BF special which was a smoking deal.
And even if I paid the full $995 for it I still think it is a super great deal for the power gains seen.

 

BigCat,

I am close to ordering my ECU upgrade from Stuart. Can you describe the difference in the car power, shifting etc after the tune.

Thx

 

Joe: Just like my XFR was this tune behaves the same way. The power comes on very linear and not violent like most other FI cars. When driving normal or with my old lady riding shot gun I do not notice any differences at all. But when I am in Dynamic mode and go over a specific throttle % you can really feel the car pull hard and is a huge improvement. I honestly feel this is how the car should have been marketed by JLR as it now feels very much alive. Knowing that JLR now has a 400hp F-Type V6 I think this tune is the same as that but with a sprinkle more power on top. I now have about 100 miles on it and I can't keep my foot of the gas. I bet adding the lower pulley would make this car perfect!

I know that the XE-R Sport is R inspired and not a true R but I do think JLR should have marketed this V6 35 T car as follows:

Base 35T = 340hp
R-Sport 35T= 380hp
S 35T = 400hp
VAP Tune = 424hp
VAP tune w/ crank pulley = 460

BTW, all pulls were made in 4th gear due to the stock tune being limited at 120MPH

 

Thanks for posting the results BigCat09.

Definitely some serious gains especially for just an ECU tune!

Any chance you have a dyno sheet showing engine RPM instead of wheel speed on the X-axis? It's much more intuitive (to me, and perhaps others) to make comparisons in this way. As we know the torque/hp curves will intersect at ~5300 RPM the torque gains will be more easily compared (and we can see where the peak torque comes on in the rev range, etc.)

Thanks again, and in either case, it's really nice that you've done this dyno and shared it with us.