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Top Speed too slow

2553 Views 49 Replies 28 Participants Last post by  navypbr
Does anybody know if the 151mph top speed is due to the gearing or is it electronically controlled. It seems to pull all the wat to the red line in 4th gear but when put into 5th it only gains 5mph more and only revs to 4500rpms.
I sure would like to do 180mph...... or more!
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you may be right, but how fast are you really going to drive?

A Speedometer marked to 220mph would be interesting (numbers might get 'crowded' though)
I hope you're trying those speeds on a track somewhere and not on the street.
I have never been 180mph before. I've maxed out my BULLITT on several occasions, and ot leaves me begging for more. I guess my question is do i have to super charge it to go faster (because of the gearing)? Or can I use weight reduction and recalibrate the computer so it will allow a higher top speed to reach 180mph.
DSG 56 said:
I hope you're trying those speeds on a track somewhere and not on the street.


No not on a track. Usually on deserted roads and once in awhile on the interstate if a vette pulls up next to me!
The Bullitt is governed to 151 per several marketing sheets. I think that Ford did this because of Areo. This car is up in the air.
So it is a governing device and can be shut off so the top speed stock should be higher?
The 01s could only manage around 150. I think the engine is pretty much tapped out at 150. Best place to try it is the dyno. I know at least on the 01s, the rear end starts lifting about 130, no down force. So even if you wanted to go 180 I don't think it would be a great idea given the lack of aerodynamics on the car.
09 Black Sunshine said:
So it is a governing device and can be shut off so the top speed stock should be higher?
If believe you can adjust the governor using an after-market tuner like an XCAL III.
droopysbullitt said:
The 01s could only manage around 150. I think the engine is pretty much tapped out at 150. Best place to try it is the dyno. I know at least on the 01s, the rear end starts lifting about 130, no down force. So even if you wanted to go 180 I don't think it would be a great idea given the lack of aerodynamics on the car.


You're probably right. At 130mph I took a small curve and hit a bump in the road. Man I neede to change my pants after that! I didn't get totally sideways but enough to make me lay off the throttle the rest of the day.
The Computer shuts it down at 151 MPH. I have not tried it personally, but feel sure it will shut you down at that speed. You will have to use a "tuner" to change the programming in the computer to get beyond that. Also, be warned, these cars (as well as most any car made today) are equiped with a "back box" that is recording this information. The dealership (for warranty purpose) or law enforcement can dump the contents of this black box to see how you have been driving. If you are involved in an accident, they will know how fast you were going, how hard the accelator was pressed or how much braking was taking place at the time of the accident. I can only guess how long it will be before the insurance companies get wind of this and try to use the black box to deny coverage.
When Car & Driver tested the Bullitt they said the top speed was 151 mph and it was drag-limited. To get more, you'd probably have to improve the aerodynamics or change the gearing so the engine is more into the peak hp/torque curve at those speeds. At roughly 30 mph/1000 rpm in 5th, you should be at roughly 5000 rpm at 150 mph...a bit off the peak power.

I used to have an '86 GT and the gearing was pretty much 180 degrees opposite the Bullitt...5 speed O/D and a 2.73 rear axle. Ya couldn't even get it into 5th below about 65 mph. The net result was the car had a higher top speed in 4th than in 5th...just couldn't climb up on the power curve in 5th.

Have fun, I however have zero intention of going that fast in it. Just one pilot or mechanical screw-up at that speed in a street car and it's "adios folks".

mogul2us
JackDW - 852 said:
The Computer shuts it down at 151 MPH. I have not tried it personally, but feel sure it will shut you down at that speed. You will have to use a "tuner" to change the programming in the computer to get beyond that. Also, be warned, these cars (as well as most any car made today) are equiped with a "back box" that is recording this information. The dealership (for warranty purpose) or law enforcement can dump the contents of this black box to see how you have been driving. If you are involved in an accident, they will know how fast you were going, how hard the accelator was pressed or how much braking was taking place at the time of the accident. I can only guess how long it will be before the insurance companies get wind of this and try to use the black box to deny coverage.

I've never heard of a black box before. How do I disable this evil device? I know there has to be a way.
It is a black Bullitt, therefore you can put a spoiler and ground effects on it. :rolleyes: :wink:
09 Black Sunshine said:
I've never heard of a black box before. How do I disable this evil device? I know there has to be a way.
It's a figure of speech - there's no "real" black box - it's just a "snapshot" of the ECU data stream for the 5-seconds prior to airbag-deployment that's saved in non-volitile memory. Things like RPM, groundspeed, throttle position, braking, etc. Ford also apparently has a few "Warranty Related" items that they save in the same way - but it just records peak-values and timestamps it: top speed, number of times the engine's been on the rev-limiter, whether or not the ECU has been re-flashed (for performance) and so on.

There are also data-recorders you can buy to record selected data points - these just plug-into the diagnostic-connector, then you pull them off and upload the data to a PC. Some Insurance Companies are offering discounts to some drivers to use a slightly more-sophisticated version of these that include G-forces for braking and acceleration.

The data is "yours" - YOU own it - not Ford, not the Insurance Company, Not the Police. YOU must give permission for it to be "harvested" (unless of course, you've got a company vehicle - then it belongs to your Employer).

There hasn't been any Trial involving this data so far as I've heard - but it's certain to happen in the future; and that will further-solidify or completely abolish the 4th and 5th Amendments of the U.S. Constitution.


All that said, now I must request that you really-do TAKE IT TO THE TRACK if you Please. I certainly don't wish to meet you if you're going to act like an Idiot out on the highways. Yeah, I like to drive Fast too - but there's Fast, and there's FAST - and you're creeping up-into the FAST category, and I daresay that as good as you believe you can drive -

It.

Is.

Not.

Good.

Enough.

Period.

I can surmise this, as if you'd had TRUE experience driving FAST on a Track or at a Driving School - you'd know-better, and wouldn't do something so Abysmally Stupid on Public Roads.
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09 Black Sunshine said:
I've never heard of a black box before. How do I disable this evil device? I know there has to be a way.
Unfortunately you most likely can't disable it! From numerous threads on other Mustang forums that "evil device" is pretty well integrated into the car's electronics.
JC2954 said:
It's a figure of speech - there's no "real" black box - it's just a "snapshot" of the ECU data stream for the 5-seconds prior to airbag-deployment that's saved in non-volitile memory. Things like RPM, groundspeed, throttle position, braking, etc. Ford also apparently has a few "Warranty Related" items that they save in the same way - but it just records peak-values and timestamps it: top speed, number of times the engine's been on the rev-limiter, whether or not the ECU has been re-flashed (for performance) and so on.

There are also data-recorders you can buy to record selected data points - these just plug-into the diagnostic-connector, then you pull them off and upload the data to a PC. Some Insurance Companies are offering discounts to some drivers to use a slightly more-sophisticated version of these that include G-forces for braking and acceleration.

The data is "yours" - YOU own it - not Ford, not the Insurance Company, Not the Police. YOU must give permission for it to be "harvested" (unless of course, you've got a company vehicle - then it belongs to your Employer).

There hasn't been any Trial involving this data so far as I've heard - but it's certain to happen in the future; and that will further-solidify or completely abolish the 4th and 5th Amendments of the U.S. Constitution.


All that said, now I must request that you really-do TAKE IT TO THE TRACK if you Please. I certainly don't wish to meet you if you're going to act like an Idiot out on the highways. Yeah, I like to drive Fast too - but there's Fast, and there's FAST - and you're creeping up-into the FAST category, and I daresay that as good as you believe you can drive -

It.

Is.

Not.

Good.

Enough.

Period.

I can surmise this, as if you'd had TRUE experience driving FAST on a Track or at a Driving School - you'd know-better, and wouldn't do something so Abysmally Stupid on Public Roads.



Thanks for the info.
And you are right, I have no TRUE experience driving fast, my last mustang would only do 135mph. But some day I will.
Regardless of the block box this car is areo limmited....180 totally impossible..not anywhere near enough horsepower to overcome the areodrag...There might be more beyond 151 but not a whole lot..high 150s at best.

A stock 05-07 C 6 Corvette with an aero slickness well beyond the 'box' of the Mustang and at 400 hp with better tranny gearing was able to hit 186... An older C5 also with aero numbers well beyond the Mustang and 350 hp only hit 174...
Mustang 3 said:
Regardless of the block box this car is areo limmited....180 totally impossible..not anywhere near enough horsepower to overcome the areodrag...There might be more beyond 151 but not a whole lot..high 150s at best.

A stock 05-07 C 6 Corvette with an aero slickness well beyond the 'box' of the Mustang and at 400 hp with better tranny gearing was able to hit 186... An older C5 also with aero numbers well beyond the Mustang and 350 hp only hit 174...

If we have such bad aero dynamics, less horde power and an inadequate transmission why is it I whip every vette (besides ZO6) I see? heh heh!!!!
mogul2us said:
When Car & Driver tested the Bullitt they said the top speed was 151 mph and it was drag-limited. To get more, you'd probably have to improve the aerodynamics or change the gearing so the engine is more into the peak hp/torque curve at those speeds. At roughly 30 mph/1000 rpm in 5th, you should be at roughly 5000 rpm at 150 mph...a bit off the peak power.

I used to have an '86 GT and the gearing was pretty much 180 degrees opposite the Bullitt...5 speed O/D and a 2.73 rear axle. Ya couldn't even get it into 5th below about 65 mph. The net result was the car had a higher top speed in 4th than in 5th...just couldn't climb up on the power curve in 5th.

mogul2us
Aside from the speed limiter, which can be removed, the car is drag limited as stated above due to the gearing and the HP available in 5th gear. With more HP you can go faster. But ... as said in this thread the car has not be engineered to do so. I went over 165 in a modified Firebird Firehawk (controlled conditions) and the windows started pulling open due to the lower air pressure going past the car! This is an interesting discussion but it really has no practical value except for a track, I wouldn't touch the speed limiter personally.

As for the big brother data logger, you can crawl out of your smoking wreak and reverse the polarity on the control module and put an end to that. The standard GT computer cost about $300. If you are really paranoid, keep one in the car and change them out when you feel someone will find out what you have been doing with your personal property. :smile: Also as mentioned in the thread, there is some debate as to who can access this information. I would not be confident of the security of the data if I were speeding and hit a car and hurt someone.
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