Actually it was about 11.5:1 on the tuned 4.2L, about 10.2:1 on the stock tune. On your dyno sheet in the first post.

The fuelling strategy on the 5.0L is very different to the 4.2L, because the 5.0L is direct injection. The stock 5.0L is very lean at light load & part throttle, and at WOT until the VVT switches, that's just how they do it, which is another reason why the AFR curve on the 5.0L looks a bit strange.

 

Sorry, you are right. I was looking at the original printed graph without the written notes when I made the post.

 

I did another dyno run today. Unfortunately they haven't combined this run with my previous one so I have had a quick play with a graphics package to superimpose them.

There is a decent improvement in power. Torque has gone from 614Nm to 674Nm and power has gone from 463rwhp to 502rwhp. If you assume a 10% drivetrain loss that puts it bang on the power of the XKR-S.

Not bad for just adding an x-pipe and 20 minutes with SDD applying the XKR-S tune!

Next step is a smaller supercharger pulley.

 

Good stuff, it's on the right path.

 

We had the last drag meeting of the year today so I did some runs with my new, improved 2010 XKR. The standing quarter times haven't shown great improvement with the XKR-S tune but that is probably down to my traction issues (12.521 v 12.533).

The terminal speed however has jumped from 115.73 to 118.50.

It has been a bit of a motor racing weekend because the local Jaguar Drivers club hired the race circuit for the afternoon on Saturday so we got to do quite a few high speed laps. I took great delight in pulling away from a 2016 Aston Martin DB9 GT on the start/finish straight.

One of the members brought along his D Type which judging by the date of registration is a genuine original.

Someone else had a racing E Type which was far quicker than mine through the bends but I left him for dead on the straights. He came over to complement me on the power of my car afterwards.

 

The mph is smack on 117-118mph however that 60ft is very nasty

Drop the 60ft and low 12s are achievable out of interest what tyres as you running on the rear

 

The tyres are OEM Dunlop SportsMaxx's. Unfortunately the car came with them and there is loads of tread left so I am loathe to replace them for the sake of it although they are noisy and don't grip very well.

My 4.2 had the same tyres on when I first bought it and I switched to Michelin Pilot Super Sports when I got a terminal puncture in one tyre and the Michelins were so much better.

As soon as I can justify it I will get some of the new Michelin Pilot 4S's

 

The pilot 4's seem to be the stickiest tread getting around I know Cambo has been putting down some decent times and he runs them

Will be interesting to see how much faster your xkr goes once fitted with them

 

A few videos of my day at the drags.

My 2010 XKR v 2009 Mercedes AMG CLS 63. On paper it should be a good match for a standard XKR as it has 507 bhp but with the XKR-S tune I was able to leave him behind quite comfortably:


A Dodge Charger (I think). He had racing slicks so got a much better start. I lost that one by 0.006 seconds so another foot or so and I would have had him.

The white Nissan GTR you see at the beginning of the video is owned by the guy who does my dyno runs and he did a 9.8 second run before getting his wrists slapped for running in less that 11 secs without a roll cage. It is one fast car!


This is just a drivers eye view of the drag circuit. I wasn't racing anyone so turned my camera to look forward:


I was pleased to see in the stats for Sunday's meet that I had the best reaction time in my class of 0.00745 and 4 of my runs made it in to the top 25 (0.00745, 0.06020, 0.08666 and 0.12707) so I have got that side of it sorted. Now I just have to sort out the traction!

The last video is of a drive by of a D Type and racing E Type at the local Jaguar club meet:

 

Your doing us proud don't see enough jags getting down the strip 😀😀

 

That purple car is what NZ calls a Dodge Charger???
Nah:



Great vids though.

 

OK, so I have been trying to identify exactly what car that was, and have not been able to. The Purple suggests Mopar, but I can't place it.

 

I just asked some FB buddies, maybe they will know. Course, NZ means 'maybe not'.

 

Is it an AMC Hornet? Nope my buddy just told me its an Australian Chrysler Charger / Chrysler Valiant Charger https://en.wikipedia.org/wiki/Chrysler_Valiant_Charger

 

I looked at as many American cars in the 65-75 era as I could find, including AMC. Could not find one that looks like it.

 

See my above edit ^^

 

Yep, that looks like it!

 

Is it just me or does the rear window trunk area resemble the XJS?

 

Thanks. I remembered it having Charger on the rear and have only heard of the Dodge Charger so thought it might be that.

Apologies to my Aussie cousins!

 

Regardless of what you almost (and would have) whupped, still great video.