does anybody know what speed the stock governor is set at?

 

I believe mine is set at 105 mph. 2001 f150 xlt v8 5.4

 

UM my fathers F250 5.4l is about 110mph. Be for it shut down he has a manual tranny and this is whats on the ticket so who knows.

 

My '99 4.6 5-sp( pure stock) shuts off at 97mph!!

 

Before the chip, I swear I saw 95mph when it shut down. I've heard it said that it is between 98mph and 108mph. I've also heard it said that the rpm limiter is set at 5400 in the v8's.
The chip allows me to exceede 95. In fact I think it would keep going untill the rpm limiter shut it down. The tires I have (T rated) are only rated for 108 so I don't think I will push my luck!

 

So, even if you have a chip to take off the limiter, there still is an RPM limiter? Plus how can you tell what your tire rating is for speed, and what will happen if you start to exeed that tire speed?

 

The speed rating can be found as a letter on the sidewall.

Q Up to 100mph
S Up to 112mph
T Up to 118mph
U Up to 124mph
H Up to 130mph
V Up to 149mph
W Up to 168mph
Y Up to 186mph
Z 149mph and over

These are the most common ones, actually tires can be rated for as low as 3 mph max speed. My Super Swampers are only rated for 80 mph.

If you exceed the speed rating there is always the possibility that the tire could blow out, and losing a tire at 150MPH doesn't sound much like fun.

-Jon

 

I've kissed 100 before, so I think mine's set for 103 mph... see truck below if it helps at all.

-Flea

 

W Up to 168mph
Y Up to 186mph
Z 149mph and over

So, which one is best for speed? Can Z rated tires handle speeds in excess of 186 mph?

 

1. Don't worry about hitting the rev limiter in while in top gear in your truck. You will never do it unless maybe you have 5.11 gears and very small diameter tires. Your accelleration will be stopped by aero drag way before you reach 5400 RPM in top gear. A simple way to see what your theorical 'top speed' could be (if aero and mechanical drag was not an issue) is to check your speed in top gear at 1000 RPM and multiply by 5.4. For example my '99 Expy with 3.73 gears rolls about 31 mph @ 100 rpm >edit 1000 RPM< in top gear x 5.4 = 167.4 MPH. That speed would never be obtained without a serious injection of HP to overcome drag.

2. see above post regarding tire speed rating and remember that these ratings are based on new, properly inflated tires running at considerably less then max load, in labratory environments (no potholes) and no ones life is at risk for the 30 minutes a tire must be able to survive at the rated speed.

If you exceed your tires rated speed you will at the very least be putting your drivers lic at risk. At worst, uh can you say Firestone? Yes many of those Explorers were overloaded and running underinflated tires in hot weather but still, tread sepatation at speed is not fun.

 

I believe originally Z rated tires were the fastest rated for 149mph and over. As cars have gotten faster and faster over the last ten years (topping out well over 150) they have since then come up with the W and Y rating which are designed for a faster speed rating than the Z rated tires... I doubt anyone in a F-150 is gonna have to worry about it very much though as not to many of us have seen 150!

 

STX/98 - Yeah I have to agree with you on that. Even though my L has the ability to go 150 it will never do it with me in it. I was just curious because the list posted by Ford4ever says the W goes up to 168mph and the Y goes up to 186mph. Now they say the Z can handle 149mph and over. Maybe the Z is only rated to 149 and that's it. Anyway, thanks for the reply.

 

I had my truck up to 100MPH once I heard the factroy sets the limiter anywhere from 98 to 108 depending on how it is equiped such as tires payload and so on.

 

befor i got my truck my father got pulled doing 120 in it but in a 95 you can just pull fuse number 8 and it will shut down the speed limiter. he was at about 4000-4500 rpm

 

well i know it's over 105 cause thwe speedo stops at 100 and goes about 5 mph till it pegs out and it used to take a while to get to the limiter but now it gets there pretty quick.