2012 XF 5.0 NA came with H rated tires

 

Not pretty sure, completely sure. This decision, like several others made by Jaguar USA (not the factory), was made by Marketing and not Engineering.

 

Yeah, but how do you know the decision was not made to lower top end in order to furnish cheaper tires and not the other way around?

 

Second verification on the top end for the N.A. Now, I am motivated and determined to get that Tune done so that can be removed. I am also contemplating wetting this Jag as well. Maybe a 50 shot.

 

If you want more power in an XF, ditch the base model before you spend too much on it and get an XF Supercharged or XFR. I wouldn't waste the money and risk the reliability issues of nitrous for what comes very reliably from the factory. With that switch you also get adjustable suspension and bigger brakes, etc.

Otherwise, just modify it aesthetically and enjoy!

 

My 2010 XF SC, which came with the ZR20 97Y rated tires (186 mph), seems to be limited to neither 121, 123, 155 nor 162 mph. Someone who isn't me had it up to 165 and it was still accelerating hard when that person had to lift off because he or she was catching up with traffic.

Maybe a previous owner had the limiter removed, I do not know.

 

First, cool collection of cars in your sig!

Second, I would agree with Kyanite that adding spray on to this car is probably more trouble than it's worth. The R or RS would probably still destroy a 50-shot on a natural motor. But I could be wrong. Let us know if you get a wet system working if you decide to go that route.

 

will do.. I am pretty sure that I will never need the top end of the S/C or R models and the torque curves in the meat of the RPM range seems to be very similar on the N.A. versus the S/C and R versions, so I think a shot in that RPM range would give me the boost comparable to what you guys have. I don't think wetting the car is going to cause any trouble. all im doing is the same thing a S/C is doing...providing cooler air, in this case via vaporized gas, into the intake. anyways, that's a discussion for another thread.

 

i have the same car, a 2012 NA 5.0. i've had it up to 130 more than once and it was solid as a rock. it felt like there was a lot more left to go, though obviously a limiter could kick in at any time.

my most frustrating experience in a car a couple of years ago was renting a mustang for a cross country trip. i didn't find out it had a limiter AT 80 FRICKING MPH until we got out on the freeway.

 

Just read an article about using nitrous on a 600cc sportbike to get to literbike power. They did it, but burnt a spark plug up and scarred a piston. My question about nitrous is how will you change the ignition timing when the nitrous is activated?

 

wouldn't the tune do this? I am assuming that one would also have the option to install an MSD module to pull back timing 1.5 degrees for the shot. the ECu would not have time to correct for that. Also, running 93 octane, which I do exclusively anyways counteracts the need to pull back to some extent. Running colder plugs too. i don't build them..i just drive them. I leave the building to the builders and the tuning to the tuners.

 

Understood. I've never messed with nitrous and don't know the in's and out's. The change of timing was truly a question. Was just pointing out that even when professionals are involved, strange things can happen when running it. It's always scared me too much to run.

Have you thought about water/meth instead? I researched it for my car and the benefit would have been there, but the extra plumbing would make any extended warranty claims related to the drivetrain nearly impossible. And I don't use more than about 3/4 of the pedal 90% of the time, so I realized I should stop the modifications.

 

The tune would do it, but I think you are dreaming about any MSD module to do that!

 

lol..yeah..i think i'll just stop at the tune and high flow mufflers. Forget about the sport cats and the NOS kit. I just looked at the specs for the 2016 mustang gt's and the 2016 Camaro SS..both of those cars could take an XFR and wipe their asses with it in the 0-60. I live in Texas, where those cars are about as common as a hooker with an std. I'm not going to mess with nitrous and still get smoked out of the hole by a kid in a 35K coupe that has 455hp out of the box and has a 4.0 time in the 0-60. It's hard to believe they got those kind of numbers. Wonder what they can get with a tune ...lol... the camaro at least has a 6.2L block to work with, but mustang gets 435 HP in a 5.0L. It's probably engineering that was taken from Jaguar at the time Ford owned it. I notice alot of Jaguar design principles in the ford product out on the road. Now, I know those are not apple to apples comparisons. I am just comparing raw numbers and ROI. I would still take my XF over all of those for the exclusivity factor alone Hell I would still choose a pre 2016 model XF over the new one ...so I stop at a tune and rear box replacement and be happy. Thank you Kyanite for talking me down from the ledge.

 

I wouldn't worry too much about 0-60 times and getting whooped by a 2016 Mustang or Camaro by a few fractions of a second. The XF 5.0 is still plenty fast, both the supercharged one and the naturally aspirated one.

And at the end of the day, even if they beat you by a car length at the lights, you're still in an effing Jaguar and they're driving a dime a dozen Ford or Chevy that'll be worth less than 15 grand just a few years from now.

I'm not hating on Fords or Chevys, I just wanna point that out! I still own the 2013 Mustang in my sig and I enjoyed driving it for two years, but at the end of the day it's a dime a dozen car and it lacks the refinement of a Jaguar, a BMW or any of the other premium brands. It just never made me feel special, even though it's fast off the line (especially the V8 versions).

 

The 2016's are faster for the pony cars, but for reference, when I went to Fontana the Camaros and Mustangs that weren't modified too much (I know they did the exhaust because I could hear it and some were wearing drag radials) were running about .5 seconds and about 5mph slower than I was. So felt pretty good about myself and my peers (two other XFR's went as well). We shocked a lot of people that day.

I have a very good friend with an 08 GT500. He's done a tune, exhaust and intake. Makes very similar horsepower and more torque, but he never has beat me in a speed contest unless I messed up. And the interior quality is so sub-par. So XFR with quality mods will do quite well against the domestics.

And I'm glad you recognized the proper purpose of the car. It's a gentlemen's express. It's heavy and not really built to take the punishment. I sheared an axle at the dragstrip. Broke cleanly halfway up the shaft. First time I've mentioned it here on the forum even though it happened last October. Still have extended warranty so I've been a bit paranoid about to publicize it because it would be really easy for an adjuster/inspector to find my mods and figure out what's really happening with it if I have future problems.

But I really needed to share it to warn others. Should start a new thread but don't want to draw that much attention.

 

Anyone know what the 2009 XF SC is, I presume 12x but just academically interested, I've never even hit 100, honestly officer.....

 

I do 110 all the time entering the freeway. Like a personal 1/4 mile track if I get lucky.

 

Isn't that normal traffic speed? Oh wait, LA. 55 max? That place is crazy
85-90 is fairly normal flow during non-rush hour on the tollways here. 110 will get you a red card tho.

 

I usually go between 78 and 85 on the freeway, when you can actually go that fast (traffic). You can go up to 80 in most circumstances without getting a second look.

Texas is crazy if it's 110 before you have issues. I'm fine with the speed if it were all well maintained cars with good drivers. I made a lane change from the #3 lane to the #2 at 80 and was almost run over by a crappy econobox doing at least 95. And he didnt change over to the unoccupied #1 lane. That scared me because I didn't know if he could stop that fast and I didn't want to go to the #1 and have him swerve right as I did as well.

I must look weird to those already on the freeway that I come on with such speed then brake to merge and am still going 80.