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Track Key Max MPH Limit

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jas427 said:
Has anyone ran with the Track Key to 7500 RPMs in 5th???. And if so what was your speed and did the Rev limiter kick in. Just want to compare with my runs. THANKS
I was told the limiting factor is the driveshaft, but I can't confirm that 100%. That would mean that the speed limiter is going to be the same on TK as it is on the black key. Bottom line there are a number of components the manufacturer has to engineer to meet certain top speeds including, tires, aero, pulleys, belts, hubs, driveshafts and many more.

There have been those that say they've exceeded 155mph on the factory speedometer, but I've yet to see anyone with a GPS confirmed speed above that. The factory speedometers are set up to read slightly higher than actual, and this difference grows dramatically as you exceed 100 mph. e.g. I have a GPS track timer with speedometer. At highway speeds of 75 mph, the factory speedo reads 78-79 mph. On big tracks I've been to 160 mph in my GT500 (corrected for tire size) and the speedometer read 175! In the Boss I've run the factory speedometer past 160 on the track, but the true GPS indicated speed was 150 mph.


BOSS LS #469
Thanks Gary
Do you know if the Rev limiter works at 7500 in all gears??? And if so then at 7500 on the Rev limiter in 5th doing the math thats just over 160 mph. Right So if I hit the limiter in 5th with the Track Key and can't reach it with the black key then the Track must move up the Speed limiter correct??? So the black key speed limits in 5th to 155mph but with the Track Key it lets it stop against the Rev limiter???

What do you think is this right or am I missing something???. I will use my GPS to Confirm Speeds on Next Runs.
The rev limiter works the same no matter what gear you are in, 7500 and that is it.

I have recorded 171.9, 166.5, 166.0 and other speeds in the low 160's. I have no doubt the car went faster then 160 but I do not know about the 171.9. The GPS did record this but it could have been an anomaly. When I spoke with someone at Ford about it they called the engineers on the Trackey program to find out if the speed limiter was changed. They way he explained to me is he asked them several times to try to squeeze out any hidden small increase that was not suppose to made public. The bottom line is no, they said no way, no changes were made.

However they did say the speed limiter will not slow the car. So like in my case if I was passing 155 at a high rate of increase the car will go passed the 155 mark. Problem is at that speed you are not increasing speed a whole lot like down low and getting an extra 17 MPH is hard to believe. 160 is easy to believe and it may have been possible to get the 166 but that is pushing it.


BOSS LS #469
OK made a trip out to my test road which is private, and used for farm vehicles only. Set up the video and gps and made a blast with the track key. It hit the rev limiter in 5th and only measured 154 on the gps. I think the gps upload rate may be to slow. This was about 1 and 1/2 miles start to finish. Made 2 more passes with the Black key and in the same distance couldn't even reach 130mph. The track Key pulls 5th much better then the black. I couldn't get the black key passes to load mph on the video so no real reason to post them. But did get the Track Key pass to load ok. This thing sounds awsome. Hope you guys can tell me how this works, 7500 in 5th but only reachs 154mph on the gps. should be 160 with all stock tires and gear. I guess Ford didn't change the speed limiter????
You're correct that 7500 in 5th with the stock tires should be 160.98 MPH. I'm a bit puzzled by the 130 with black key in a mile and a half though. The car traps the 1/4 at roughly 115 mph, peaks in 4th at 121 mph and pulls pretty hard in 5th. The only times I've had it up to 150 was at BIR at the end of a one mile straightaway, but that's coming out of Turn 10 at around 50 mph.

The one thing that makes me curious is TK's potential impact on track times. While I'd love to think I'm going to run 20-25 mph faster in the straights with TK, I somehow doubt that will happen.
Does anyone know how the speed limiter is implemented? Is it a gas shut-off or similar to the rev limiter?


Because racecar.
Arizona, USA
On the dyno, the TK would pull up to redline in 5th (7500) at an (indicated) 160ish mph.

You going to be doing some top-speed driving somewhere? lol

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