Have a look in the Motorsports section here on the forum L80OUS, there is a list of all the 1/4 miles from forum members, as well as one from Santa Pod in the UK, your mph is about right, but ET a little slow compared to other X308 XJR's.

 

It was my first go on the drag strip so I was struggling to get the car moving off the mark. Could the extra weight of petrol and my fat *** lead to the car being 0.2/3 seconds slower?
My technique was foot on brake with about 2000rpm.

Tyres are good, Potenzas with about 4mm left, temp was around 15c.

 

Yes, extra petrol and your fat *** will affect your time.

lower petrol and better reaction time will get you in the 13's where you should be. Did you try traction control on or off?

 

Better reaction time has nothing to do with better ET. Main point is good 60ft time. If you drive with almost empty tank you may lose traction more than you get benefit from lower weight. If you move yourself ( 127kg ) to the trunk - that's the best way for good times

 

Cheers for the advice, should be going back for another go soon so me and the car will go on a diet and I'll let you know how I get on.

 

There is a delicate balance on the rear weight with acceleration... too much fuel, not enough rear weight, etc etc... depends on various things... tire/wheel weight, removal of your spare tire... whether you lightened your hood, custom exhaust.. etc etc... stock vehicle, i was getting my best 1/4 mile time with a 1/4 full tank of fuel.

Hell...i bought 255/35/18 wheels that weighed 21/22lbs vs the 29/30lbs it usually has with 255/40/18... what a difference on acceleration that was, felt like a go kart lol.

I'd REALLY like a carbon fiber or aluminum driveshaft with lighter wheels/tires to see what kind of difference that would make.

 

Fellas, guess what?

 

What? 11.80??

 

Yeah, close enough: 11.924 @ 118.82 mph.

Car 42






Track: Empire Dragway/NYIRP
Elevation: 910'
Temperature: 64 F
Humidity: 40%
Baro: 30.11
Density altitude 1340


Changes from previous runs:

OS Giken lsd

265/40/18 Michelin PS2 on 18x9 BBS Milans (wider but heavier) vs old bald Pirelli PZeros 255/40/18 on 18x8 Pentas.

Maxbored throttle body.

Oh and nearly forgot, AMG blue top valve solenoids.

I'll try to get some videos up if they're any good on Monday.

 

That is simply awesome!

118.8 is a strong finish.

I believe that puts you at the top of the list as well as makes you the fastest X308 XJR in history to date.

 

Yup, top of our 1/4 mile list and fastest XJR that I've seen. Feels good to beat the new 5.0 XFR's and XKR's with a lowly 1999 4.0

According to Dragtimes, there are only two Jaguars with Jag engines that are faster and one of them is the XJ220 supercar.

You twin screwed XKR's need to step up to the plate

 

Not lowly as the X308s still look WAY better

I see Matt Moran ran a 1.775 60 foot time to your 1.89, so there is still room for improvement, maybe you can get to 11.8x

At any rate, you have a proven 11 second comfortable beautiful Jaguar.

Well done,...well done.

 

Congrats Steve! Awesome result!

 

Don't forget that Bigcat9 5.0SC car was tuned, and had even more power than XKR-S

Great result!

 

Congrats! Great result.

Waterdragon: Moran used ProTorque high stall speed TC. This is a big advantage if good tires and fast track. He had this differential:
Jaguar XJS XJRS Kit Car 2.87 Power Lock Limited Slip Differential | eBay

 

Mat mentioned he got about 0.1 sec from the 60ft by changing to the high stall converter, but I guess the drawback is the normal street driving will be affected.

 

I thought Mat said he got only .1 second from the LSD, but it took care of his wheel spin issue.

For my purposes, I would not consider a stall converter, since I like how my XJR is so comfortable and docile like my XJ8 until I stick my foot in it.

 

Damn, as a drag racer of over 8 years, get that to a 1.8 60ft and you got mid 11s

 

That's fast, nice one!

 

Thanks guys. And a big thanks to Avos for making this possible.

Mat Moran had an earlier powerlock diff with 3.5x gears I believe, torque converter, and drag radials; all which improve acceleration.