Just wondering what the top speed is for a 14 GT with the 3.73 rear end.....

 

Go find out!

 

Depending on how efficiently you are getting torque to the tires, it should end up somewhere around 170mph without a speed limiter.

That would put you at around 5200 rpm on stock tires in 6th, if my math is right.

 

it is more than 145Mph ... and I have an auto (3.15)

 

Unless you have some serious HP, there is no way that you will ever get one of these cars to 170MPH. Not going to happen even if the speed governor was removed. The stock 420HP just isn't enough to overcome the aero drag.

 

I think you have a good point about drag, particularly since the aerodynamic profile of our cars is similar to the empire state building.

With that said I'd expect the car to be able to do 165mph or so ungoverned. Does anyone know what the 11-14s are governed at? Is it 155?

 

I was using assumed numbers for drag coefficient, area, and torque. I don't have access to any of that information.

With that in mind, the 2005-2010 GT could reach about 150mph (300hp) or so, and the 2013 GT500 could hit 200mph (650hp). So even elementary interpolation puts 420hp a bit more than 165mph.

 

Maybe going downhill. LOL. Albeit true the GT500 can hit 200 MPH, that car also has some real serious power. I also believe the 682 HP it's rated at is conservative. Who the hell knows. Maybe you're right. Maybe it can hit 165 MPH with a stock powertrain.

I just think stock cars and they have like 800 HP, slippery bodies and they can barely hit over 200 MPH at Daytona. And that track is 2.5 miles around with banking. So I struggle thinking 420 is going to get me to 165 in a car no where near as slippery as a stock car.

 

Some one on this site has had to have run one of these cars all out with out a speed limiter!
My guess would be between 160 - 165mph!

 

160 should be doable with enough track. Folks doing mile runs in stock and mostly stock (tune + exhaust, usually) Mustang GTs are hitting 15x MPH fairly consistently.

I wouldn't necessarily say that something like a NASCAR stock car is "slippery"...probably more so then most factory vehicles, but they do generate considerable downforce, which will hinder top speed. They are purpose built for the tracks they see - none of which are just a huge straight line with pure top speed in mind.

 

Yup. Jus go fayest and tarn layeft.

 

True. Which brings about another issue. Do our cars produce enough downforce for those speeds?

 

On the front end? Probably enough to hit 160...stock shelby's get to 200 ish, and I don't think their front end is THAT much different.

 

I am not going over 168. That is what my tires are rated at.

 

The '11-'14 GTs are governed from the factory to 147 MPH. The tune in my car eliminated that and it has gone to 150+ before I backed off. It was pulling strong so I have no doubt if could have easily gone beyond the 160 max of the speedometer. This is with an auto and 3.15's.

 

I 'think' the OP might be thinking his GT with 3.73 gears will top out 'less' than a GT with 3.15 gears. I think the top speed will be the same, drag limited

 

150 I believe. But the speedometer is going to be off a little bit. Have to use GPS to get a truer speed. Mine read 150 and still had plenty of room.... on the track of course.

3.73's are going to have a little less top-end than someone with 3.15's, and it wasn't floating around. The car felt planted. A car with poor aero is going to "float" over every little bump.

I kind of doubt Ford's claims of 200mph with the GT500 though. 190's maybe, so they probably figured "close enough".

Realize a Veyron Super Sport with 1150bhp, shaped like a bullet, has a top end of 255mph, and that's with the rear wing down and it takes a good long while to hit that speed. With the wing up, it won't hit those speeds at all. The Veyron they ran on Top Gear had 1k BHP and hit 250mph over a 5? mile stretch of track.

Before Nascar enacted restrictor plates back in the late 80's or 90's, they would and could sometimes hit over 200mph, but they were having too many incidents, and those cars look like go-karts in person. On tv, they look a lot bigger than they actually are. I'm surprised Tony Stewart can even fit through the window. lol.

As others have said I would say top end for a mostly stock auto with 3.15's is 165-168 max.

 

Not true. My car is stock and I have hit 156 in 5th on the autobahn. Not enough grunt to do it in 6th. There's a noticable difference when you shift to 6th at 155.

 

The speedo and even GPS is going to be off a little bit at those speeds and it can vary depending on the car and how well the speedometer is calibrated. GPS will be off less, but can still be off.

 

That was GPS on my phone and Tom Tom.