Picked up my R coupe in August and after some break in it was time to get her to the track.

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The track was PBIR. Great weather and some cool cars came out. There were your typical Porsches and Corvettes out, mine being the only F type. The car was a hit just standing still. It drew thumbs up from multiple people.

Ready to go…


PBIR

I dropped the tire pressures to 31 psi all around. Made sure oil level was fine. Good brake fluid is a MUST. I use Motul 600.

I ran multiple 25 min sessions. First session I left DSC on and warmed up. Then later sessions I switched to TracDSC and later in day when track was less crowded off.

Overall I was happy with performance but I noticed a few things.

1. The car feels like it wants to drift even with the nannies on it tries to go sideways. Too much power to rear wheels. I think the car would be faster with wider rear tires, maybe not as lively. Sliding may look cool but it isn't the fastest way around a corner.

2. I felt I was getting an exercise in car control in this beast. Throttle modulation was very important. I felt I had to short shift out of corners just to be able to get power down. It will be interesting to see how AWD performs on this car.

3. Brakes are fantastic. I have the ceramics and there wasn't a hit of fade. I did get a brake temp warning at the end of the day but still no fade.

4. Seats are nicely bolstered

5. The lap timer and g-meter are nice little gimmicks. You have to remember to hit the screen at start/finish to get split times (without taking eyes of the track). Thankfully the stop/start bottom is large enough.

6. Still love watching spoiler deploy and retract

7. Checking tire pressures is a PITA ans well as checking oil level. I wish Jag would put some real time tire pressure monitoring as well as some more gauges in the dash such as oil pressure etc.

8. Coolant temp didn't budge throughout the day. Although this was in January. We will see what happens in FL at Sebring in August.

9. Drove home 120 miles, in luxury.

In short it isn't really an ideal track car. I will probably track it 2 times a year max. Most of my time is spent SCCA racing my spec miata. If you want to be the fastest guy on track day then you'll be looking at a Z06, 911 GT3 etc. I had a Z06 and it was a beast on the track. However, I was willing to give up a few seconds on the track for something thats look great, sounds great, is a little unique and I can have fun with once in a while.

Don't be afraid to get your f type on the track. You won't regret it!


MC

2015 Jaguar F-type coupe
1996 Acura NSX
1995 Mazda Miata

 

When I was racing in Showroom Stock and Improved Touring (albeit a quarter century ago) we would raise the pressure on DOT tires to the 40-42 psi range to: 1) reduce side wall chatter 2) improve traction, and 3) reduce the risk of rollling the tire off the rim at full Gs. Understeer - more pressure to the front. Oversteer - more pressure to the rear. Has tire technology changed to a point where reducing pressure increases traction? I've only done that for mud and snow when 4 wheeling in the FJ40 or K1500.

 

It's not the first time I've read the suggestion on this forum of dropping tire pressure for the track and I have been puzzled. In 30 years of tracking cars that is the first time I've heard that idea. Everybody I go out with does what you do, llhoboy, and INCREASES pressure, not decreases it (as do I), and we do it for exactly the same reasons.

 

It depends on the tire. Increasing tire pressure does have the general benefits of increasing sidewall stiffness which helps keeps the softer street tires from rolling, it also helps with tire responsiveness. However, higher pressures can increase heat in the tire as well which can decrease grip. Drivers who like to slide the car around will like higher pressures. Drivers who typically like more tidy driving will favor lower pressures. Lower pressures (to a point and depending on the tire) can increase overall grip but it will be at the cost of responsiveness.

 

Jaguar recommends cold pre track pressures of 31 psi for the p-zeros. By the end of a 25 minute session my pressures were in the mid 40's. I felt the car get real twitchy at those pressures. I was willing to sacrifice a little responsiveness for more contact patch early on.


MC

2015 Jaguar F-Type R Coupe
1996 Acura NSX
1995 Mazda Miata

 

I ran low 30s cold and it made a world of difference. As Stig mentioned 31 cold is the recommendation for the P Zero. Got a little annoying because tire indicator went off

 

Not to mention the fact that Jaguar even publishes recommendations for track use is a step in the right direction in attracting new buyers.


MC

2015 Jaguar F-Type R coupe
1996 Acura NSX

 

For people that worry about too low tire pressures; my cold, starting "slick" racing tire pressures on my SCCA GT-2/3 race car were 14 psi. What you ultimately wanted was a pressure that allowed the tire surface to be flat when hot, or when measuring tire thread temperatures across the thread, provided nice and even track temperatures. If the temps on the street tire went from the starting 31 to 40+, perhaps lowering the starting pressure could be in order. But, the best way to judge would be to use a tire pyrometer to check temps across the thread immediately after coming off the track.

Increasing cold tire pressures used to be the thing to do with old, tall sidewalled street tires to prevent too much sidewall distortion. Modern, low profile sidewalls tend NOT to distort anywhere close to what the old ones did.

 

I was wondering if that was the difference.

 

Still depends on the tire. The higher performance tires are closer to older racing tires these days (stiffer sidewalls with better heat management). However, non-performance tires still act as much like jelly today as they did 20 years ago.

 

I found this series of posts interesting as 'tracking' is something I have not done much of... wonder if 'nitrogen' fill instead of regular air would reduce the amount of pressure change.
Lawrence.

 

Nope. PV=nRT regardless of the gas (though not precisely since there is no such thing as an ideal gas).

 

Agreed. Nitrogen fills are mostly (but not complete) marketing bunk.

Exxon did an interesting study comparing nitrogen to air fills on tires across a range of performance metrics with pretty much identical results:

http://www.arb.ca.gov/cc/tire-pressu...lipr051308.pdf

 

I worked with one of Australia's leading tire retailers for 17 years. They sold nitrogen fills, and it didn't matter who I asked in the company, no one could tell me what the advantage was to a nitrogen fill, other than to add to the overall profitability of the sale.

 

[QUOTE=TheStig;1136556]Picked up my R coupe in August and after some break in it was time to get her to the track.

[image
image

The track was PBIR. Great weather and some cool cars came out. There were your typical Porsches and Corvettes out, mine being the only F type. The car was a hit just standing still. It drew thumbs up from multiple people.

Ready to go…


Just a question about the car itself (wich has perfect specs in my eyes <3)
Is the color Salsa Red?

Thanks!

 

Yes. That would be salsa red.


MC

2015 Jaguar F-Type R coupe
1996 Acura NSX
1995 Mazda Miata

 

The manual says 32 front/36 rear hot. So I am wondering why you chose the same pressure all around instead of staggered by 4 lb psi?

 

Really? First time I've read that. Will need to double check.

 

Nice write up.

Are you really the Stig? Given your in Tampa I might think you are the Stig's American cousin



Although with that sexy Red F-type, perhaps you are Italian Stig?

 

He can't be the Stig. I have a t-shirt that says I'm the Stig. Pretty sure it is the only one in existence.