I've looked through the forum and can't find an appropriate thread. Just curious: I have an '07 S-Type with a naturally aspirated 4.2. Can anyone tell me what the top speed might be? While it would no doubt be fun to find out myself--I don't have access to the facilities, nor the cajones to try it myself! Thanks

 

Probably speed-limited to some value decided for your laws.

Here I think it's 155mph but the car likely cannot achieve that (guessing on the latter). Yours may be limited to 121mph as the 3.0 seems to be https://www.jaguarforums.com/forum/s...e2/#post293512.

Make sure your tires (and rest of car) are appropriate before trying it

 

I'm pretty sure JagV8 is correct. The N/A cars are limited to 121 mph while the STRs are limited to 155 mph. If they weren't limited, most likely the N/A cars would do between 140 mph and 145 mph while the STRs would be in the 165 mph to 170 mph range.

 

I know that 115 feels a lot like 65 in mine, I backed off as I didn't want to spend my vacation in a North Carolina jail.

 

I can say I have hit 145mph in my STR

 

Ahhh...yes Mike...The Texas Mile. The STR is definitely a fast machine. If untethered from the limiter, can achieve 170 + mph. My STR is capable of burying the needle in a noticeably shorter time than when it was stock. Not that I ever did bury it, since modding her the potential is definitely evident...she pulls out of the hole with much fiercer verocity and maintains much of this into the triple digits. The fastest I attempted was 135 mph. NY lacks the straights of many states, and the ticket would be tantamount to a botched "Happy Ending"... And as us guys are well aware...this sucks the big one.

 

Good move!

 

Ya I wish it was a two mile course or at least getting a running start. I want to go back out there after a few more mods.

 

Very good point Kitty - these cars mask speed amazingly well, gotta be careful. I was cruising last weekend, just kinda dawdling along and glanced at the speedo...95mph...whoa! Felt like 70 maybe.

I've done 140 mph, closed course.

On an empty highway...well too fast and I'll leave it at that.

 

Mike and all, Please don't take this as a brag-n-nag...the 3 lb. pulley will send you off the line and on your way noticeably quicker, conserving precious seconds and feet. The cooler temps. allow for extended "Fun Runs". A chiller is def. nice to for all seasons heat soak prevention.

 

I've hit 157 in my STR. The clutch engages at that speed. Look at the tires on the car too and see what they are rated for. Usually, the tires on the vehicle will better than cover the top speed the vehicle is "electronically" limited to. I.E.


L 75 mph 120 km/h
M 81 mph 130 km/h
N 87 mph 140km/h
P 93 mph 150 km/h
Q 99 mph 160 km/h
R 106 mph 170 km/h
S 112 mph 180 km/h
T 118 mph 190 km/h
U 124 mph 200 km/h
H 130 mph 210 km/h
V 149 mph 240 km/h
W 168 mph 270 km/h
Y 186 mph 300 km/h
225/50ZR16 in excess of 149 mph, 240 km/h
205/45ZR17 88W 168 mph, 270 km/h
285/35ZR19 99Y 186 mph, 300 km/h
285/35ZR19 99Y 186 mph, 300 km/h
285/35ZR19 (99Y) in excess of 186 mph, 300 km/h

This is a semi chart as there are other variables but, it's a good based from which to get an idea without getting a ticket..... or worse *LOL*

 

I've had my STR up to somewhere between 155 and 160. Not going to say where though. LOL. I HAD to try it. I saw the needle go past 155 before I started letting it slow down. I think I read somewhere that if you put the shifter in 5 rather than drive, the car will hit 170 to 175 range. Not sure about that though. Never tried it......yet.

 

I've goten the STR up to 150 on the Long Island Expressway trying to catch an E39 M5. This was well before mods, and he maintained his gap and was pulling slowly. After we let off he identified himself as a Suffolk County police officer by holding up a SCPD t-shirt (off duty). Was a good laugh.

 

I wish I could find a way of removing the speed limiter on my 3.0. 121 mph is ridiculously slow. A 1960 Jaguar Mark 2 3.8 could do 125.

 

Jaguar claims the 121 MPH limit is because of the factory tires. They did not put high speed tires on.
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(If you put safe tires on) I believe the limit can be removed but I'm not sure how many (or, few!) tuners/etc can do this. Maybe just ones over here?

 

I will confirm that the 3.0 granny's are limited to 121 MPH.

It was back in Feb. of 2009, on my way home from picking the vehicle up from the Tampa area (ebay, fly in, drive home type of deal). In Georgia, there was no one on a long flat, straight stretch of highway....so hammer down, yep ding ding 121 and the vehicle "sputtered down". I did average somewhere in the 80 MPH range for the entire trip home, just some nice sipirited driving.

Oh I did pass a new Camero at one time (a white with orange striped one), he decided to "play", so I took the ol' granny back up to 121, where he pulled along side, smiled and dusted me........... severely.

 

The 3.0 and 4.2 are limited to 121 mph, I am on my 4th S-Type, 3 V8's and one V6. The super charged are set at 155. Not sure how often you will need to go more than 100 in the states anyway, the penalties are way too costly now

 

You aren't kidding when you say other variables. Like load factor.

For heavens sake don't make any safety decisions based upon a simplistic chart such as this.

I've done a bit of open road races involving flat out top speeds for periods of well over 1/2 hour.

Consult with the tire manufacturer on the phone about what you're going to be doing.

Those speed limiters are on the cars to there for a couple of reasons but the biggest is to ensure that with the OEM approved tires at the specified air pressures you won't exceed the load rating of the tires and get yourself killed.

The load rating falls off rather quickly on these tires once you get into the triple digits. You could easily exceed the limit and lose a tire if you're not careful. I've seen it happen.

 

A Suffolk county cop driving an M5? No wonder property taxes are what they are there.