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Top Speed/Rev Limiter

Ford states the top speed of the Boss 302 is 155 MPH but we all know how those numbers don't always add up. The power rating is suppose to be at 444 Horse but we know that too is not true.

Yes, the car was built for a roadcourse but it doesn't mean it can't do well in a straight line too.

I'm not advocating or suggesting people go out see what "land speed" record they can obtain with thier car but maybe just post what you've done or have seen first hand.

Also, the Rev limiter is set but at what top speed? Most if not all limiters can be bypassed or disabled so how can this be done on the Boss?

I'm just trying to get another thread of discussion going.......since its the ONLY thing I can do until I get my Boss sometime before the years end!! :)
 
My understanding it the top speed is limited at 155 MPH and the revs are limited to 7,500. The Boss should go to around 170+ mph and the revs can go past 8,000. There is some speculation the speed is limited due to the two piece drive shaft and the revs were limited to meet Ford's long term durability goals.
 
http://shaftmasters.com/3mualdr1.html

You can get around the rev limiter and top speed with a special tune but where are you going to go above 155, I suppose I could get up that high on Sebring or Daytona but doubt I would want to push it much more. If you are into hardcore racing that is different but then I would want to be in a "S".
 
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So the Boss has a Mustang GT 2 piece driveshaft then? Hmmmm...I never really thought about the driveshaft. Anyone thinking about going to a 1 piece aluminum?
 
I can live with the Boss limiters, no problem. I'm just going to be driving my new Boss on nice curvy routes around New England so that won't affect any 155 mph limiters in the least.I'm just looking forward to hearing that sweet 444 hpw engine growl out of that quad exhaust to make me smile.
 
302BOB said:
I'm just looking forward to hearing that sweet 444 hpw engine growl out of that quad exhaust to make me smile.

Do you think ANYONE is going to leave the exhaust street stock?

My New Car Job List
1. Remove exhaust plates
 
jimprw said:
So the Boss has a Mustang GT 2 piece driveshaft then? Hmmmm...I never really thought about the driveshaft. Anyone thinking about going to a 1 piece aluminum?

I don't plan to and unless you are tracking the car 100% don't really see the need but guys like Gary could answer that better. Did you look at the link above?
 
I might play around with the side discs. I work in a machine shop, so making new ones with bigger openings could be an option. I've always loved the sound of a GT exhaust, so I'm really looking forward to what the BOSS has to offer.
 
2012Boss said:
jimprw said:
So the Boss has a Mustang GT 2 piece driveshaft then? Hmmmm...I never really thought about the driveshaft. Anyone thinking about going to a 1 piece aluminum?

I don't plan to and unless you are tracking the car 100% don't really see the need but guys like Gary could answer that better. Did you look at the link above?
I've had a one-piece in an S197 already. It's pretty hard to get the DS vibration out of them, especially without an adjustable UCA. I'm really not planning to mess with the Boss suspension so that's probably not going to happen. That said there are some lighter weight and stronger 2-piece DSs on the market. I have an aluminum/chromoly on my GT500 which did eliminate most but I don't think all of the vibration. With all the torque on that car, I needed something that would handle the power over the stocker. The only reason I'd consider a new DS for the Boss would be if it reduced weight enough to matter. The aluminum/chromoly I have weighs 27 lbs and I think the stocker is around 42? Not enough to matter IMO. Some of the one-piece CF ones I've seen weigh under 15lbs. They might be a consideration and supposedly no vibration, but I don't know anyone that has put one in their S197.

http://www.vmptuning.com/store/index.php?p=product&id=392&parent=121
 
Wow, from the looks of the stock drive shaft I would have never thought it weighted in at that much. I don't know the actual weight of a 70 Boss drive shaft but I am guessing that is less.
 
jimprw said:
So the Boss has a Mustang GT 2 piece driveshaft then? Hmmmm...I never really thought about the driveshaft. Anyone thinking about going to a 1 piece aluminum?

The 1-piece Shaftmaster's unit is rated for 7500RPM (shaft speed). That works out to 155mph with the 3.73:1 diff. If you want to go faster, you'll have to go 3.55:1 like the BOSS 302R's.
 
DigiCowboy said:
Do you think ANYONE is going to leave the exhaust street stock?

My New Car Job List
1. Remove exhaust plates

Some may leave it stock with the plates in. Others may make the opening a little bigger to allow a tad more sound out. Personally I will take mine out before I ever drive it with them in. I'm also throwing on a new axle back because I'm only young once :) That's part of the beauty of this car though. There are so many options to make it sound exactly how you want it to.
 
PTRocks said:
jimprw said:
So the Boss has a Mustang GT 2 piece driveshaft then? Hmmmm...I never really thought about the driveshaft. Anyone thinking about going to a 1 piece aluminum?

The 1-piece Shaftmaster's unit is rated for 7500RPM (shaft speed). That works out to 155mph with the 3.73:1 diff. If you want to go faster, you'll have to go 3.55:1 like the BOSS 302R's.
With the stock tire size (27.1") and 7500 RPM in 5th gear (1:1) you would be going 162 mph (without electronic limitation). 3.55s would get you to 170 but I'd be worried about the stock DS at that speed.
 
DigiCowboy said:
302BOB said:
I'm just looking forward to hearing that sweet 444 hpw engine growl out of that quad exhaust to make me smile.

Do you think ANYONE is going to leave the exhaust street stock?

My New Car Job List
1. Remove exhaust plates
I doubt I'll run mine wide open but I'm planning on opening up the hole. I will try it without the discs when I first get my Boss.
 
cloud9 said:
PTRocks said:
jimprw said:
So the Boss has a Mustang GT 2 piece driveshaft then? Hmmmm...I never really thought about the driveshaft. Anyone thinking about going to a 1 piece aluminum?

The 1-piece Shaftmaster's unit is rated for 7500RPM (shaft speed). That works out to 155mph with the 3.73:1 diff. If you want to go faster, you'll have to go 3.55:1 like the BOSS 302R's.
With the stock tire size (27.1") and 7500 RPM in 5th gear (1:1) you would be going 162 mph (without electronic limitation). 3.55s would get you to 170 but I'd be worried about the stock DS at that speed.

???Wouldn't the driveshaft be going the same speed no matter if you had 3.73 or 3.55?
 
Dean#4AI said:
cloud9 said:
PTRocks said:
jimprw said:
So the Boss has a Mustang GT 2 piece driveshaft then? Hmmmm...I never really thought about the driveshaft. Anyone thinking about going to a 1 piece aluminum?

The 1-piece Shaftmaster's unit is rated for 7500RPM (shaft speed). That works out to 155mph with the 3.73:1 diff. If you want to go faster, you'll have to go 3.55:1 like the BOSS 302R's.
With the stock tire size (27.1") and 7500 RPM in 5th gear (1:1) you would be going 162 mph (without electronic limitation). 3.55s would get you to 170 but I'd be worried about the stock DS at that speed.

???Wouldn't the driveshaft be going the same speed no matter if you had 3.73 or 3.55?

I used the calculator linked above to find road speed using rear end ratio and assuming 7500 RPM with a 1:1 transmission ratio. That way the calculator gives you road speed as a function of shaft RPM. The wheels spin at driveshaft speed divided by the rear end ratio. Here every is assuming that the driveshaft's max rated RPM is the part limiting the top speed of the vehicle.
 

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