Yeah, I will be switching to a full synthetic once I change the oil, I doubt the dealer uses anything but cheap dino oil.

My 60 ft is really what I want to improve on, it ranges from 2.163-2.170
My 1/8th mile ranged from 9.007-9.027

 

Yea...our cars definitely have traction issues. I am going to the track on October 31st...hopefully I can run right around a 13.5 trapping around 105.

I am honestly surprised that your car only turned a 13.8...more surprising is the trap speed. I know our cars should be able to trap around 105 right out of the box. Weird.

 

Your numbers do seem to be low. It's like your mods are robbing you of power instead of adding it. The trap speed is a better measure of power than the ET. Your dyno numbers were also a little low, if I recall correctly.

I also went to the drag strip yesterday, Oct. 18. My best time was 12.996 and the fastest trap speed was 107.65 mph on another run. I'm very pleased that I broke into the 12's, moreso because during that run I beat a C5 Z06 by .012 second.

Car is a 99 XJR with only exhaust and my own intake I made for mods. Total weight was 4000 lbs.

 

SteveM, your call is fast ! Details please like what tires on the rear, what track and the elevation if you know.

 

I don't know what's going on...it's frustrating, because I too believe it should be quicker. My runs are always very consistent, but, it seems it should be faster

 

throw a new fuel filter on it and change the oil to mobil 1 5w30 with a k&n oil filter and I BET YOU A DIME TO A DOLLAR YOUR TRAP SPEED GOES UP !

 

Steve, your numbers are incredible for a 4.0 XJR. If I may also ask, how were your 60ft and 1/8 mile times? I am thinking that very sticky tires may have helped you achieve a 12.9? Also, how was the ambient temperature on your runs?

Budsang, I know the Mina intake significantly increases your intake temperature while you are idling. Your times and trap speeds are almost identical to the times I put down when the ambient temperature was 110F on a 1200ft elevation track. I was using a stock airbox and the Mina exhaust.

I will be going back on the 31st to see if I can break a 13.5...the 12.997 time that Steve managed to put down has made me hopeful...

 

Patrickw813, i agree steve's car is very fast. Im guessing a street slicks also, but its only a guess.

 

Nope, no sticky tires. They are old, worn out Pirelli P zeros. One is 6 yrs old and the other is 11 yrs old! Certainly no grip. I did deflate the rear tires to around 20 psi. and inflated the fronts to 42 psi. However, looking at the numbers from when I didn't change the tire pressures, there's seems to be no difference.

My best ever 60' was 2.043. Usually it's around 2.1 and lot's of times its higher.
Track was New York International Raceway Park (NYIRP). I've seen varying numbers for the elevation but the most common is low 900's feet. Temperature was 50 deg. F. humidity was 44% and barometric press. at 30.24. The cold temp. is good for power but terrible for grip.

I also did not do a burn out this time because I put shiny new mufflers on and didn't want to get rubber on them. But according to my numbers, there is no difference whether I do a burn out or not.

Here's the time slip, car #110.





I'll see if I can post some videos.

 

nice time, but did you fall asleep at the light, lol

anyways...I am thinking it comes down to weight...maybe it is me that needs to loose some weight I also wonder how much my jag truly weighs, like how much does the rear multimedia stuff add...I do plan on getting a lighter battery...I thought about putting the battery from my nissan in it for track days, not sure if it would be sufficient though, it only weighs about 12lbs

I do not do burnouts either...I feel like it is pretty pointless to do a burnout on a car with no lsd...it is crazy that it does not come with it. I see they made a lsd for the 06 xkr...wonder if there is anyway to make it work in the xjr

 

I know the topic of an LSD in the X350 XJR's have come up quite a few times. Unfortunately, each time it is brought up, the subject of reprogramming the TCU and stability control/ABS systems comes up. The reason for this is the car will not recognize what the LSD is doing and will try and correct the outside wheel that is spinning a little faster. This will make the system go haywire...

I am pretty sure the new body 4.2L XKR's come with some sort of LSD from the factory which makes it a lot easier to adapt a new unit into the factory pumpkin without having to reprogram anything.