So finaly decided to get the beast properly dyno tuned in a few weeks.

have the first rolling road power run coming up in a few weeks and then will decide how to go on. Probably along the lines of H pipe center to go with the quicksilver rear boxes and a pulley upgrade.

The tuning company i've chosen is Viezu, they are about 10 miles away from me and have over the last six months been tuning loads of Jags and all customets appear very happy........target is to try and get to the magic 600hp..........have the luxury in the UK of 98/99 RON fuels being everywhere!!

One thing that is bugging me is that the dyno seems to be reading really low...........stock XK and XF Rs are shooting between 340 and 360 RWHP...........maybe i shouldn't worry about the readout and just focus on the gains!!!!

 

Are those for 400HP cars? That's not 400 at rear wheels...

 

Thats for the 5.0 XK and XF Rs......so the 500hp @crank cars........

 

Are you sure the Viezu dyno is reporting hp or kilowatts (kW)?
I dynoed my stock XFR a month ago and it showed 344.7 kW at the rear wheels, which converts to 462 hp:





I know, different dyno, but that difference seems too much.

 

From what I've been told Viezu is the company that's developed most of the "canned" tunes here in the US. Not sure if it's accurate, but that's the word.

 

They do a bit of both in the UK stock canned tunes and custom tuning on the rolling road.......dyno is a Mustang Dynometer.......reading up on them apparantly they all read low.......

Defo said the power was in rwhp........

 

Mustangs always show lower power. Just do a before and after making sure they use the same correction factors and 4th gear for the pull. You're really only checking for the difference in power. You should ask if they have a correction factor to compare with Dynojet. Many do.

 

Cool, thanks buddy......

Do you know anyway to stop the kickdown during 4th gear pull???? Even in manual mode the car wants to kick down........

 

Yep, having done four dyno runs in the last month, the trick is to ease the throttle down to WOT and not to mash it. Even then it will sometimes kick back to third.
Obviously, and I guess you already know this, you must completely turn off DSC (hold the DSC button down for around 12 seconds), put the car in Dynamic and "S" mode, and use the right paddle to bring up 4th gear.

 

Thanks for the tip......will keep you guys posted!!

 

So what happened? I'm considering the same setup...

 

So, had a great run on the Mustang dyno with a peak pull of 421whp @5751rpm and peak torque of 402ftIb .......the guys were saying they usually see around 370-380whp from XK and XFR.....its a Le Mans spec so no one really knows what Stratstone done to them....mine has also had alot of work done to the intake........has not had a smaller pulley so this is the next stage for me along with some further exhaust work..........i'll post up the dyno graph tomorrow and the video of the run.......

must admit i always thought it was quicker than my previous XKR!!!! i'm well chuffed!!!

 

Congrats! A good day at the dyno is a good day indeed. Looking forward to seeing the dyno chart.

 

Nice numbers! I've never heard of a Lemans Edition XFR

 

Graph below......

 

So this is purely the baseline dyno?

Pulley, exhaust and tune coming up?

 

Yes mate this is the base line run. Alrhough more output than expected......allready have Quicksilver rear boxes but going to do a H pipe and swap out the center section.....then a +1.5psi pulley and re-map.......hoping to see over 600 horses with that set up.

 

Did they not also measure AFR?

 

When are you booked in...


I had thought they'd do the baseline, fit the bits and then Dyno tune all in a day! Guess the exhaust work is the delay - I used MIJ performance in Walsall for my Mid and Rear section exhaust fabrication - can't fault their work.

 

This was a FREE power run to check all is in order before u need to comit to anything........how many places do that!! All was good so next step would be a proper pre run, pulley and tune, followed by another power run so u have before and after.......no AFR measurement on this FREE run but part of a tune package yes where they will make adjustments

i'm doing the center section myself and initially going to junk the second resonator for straight pipes......then another pwr run......i love to do things in stages so we can all see what differences it makes

Will definately be getting the pulley and re-map soon though......