I am trying to find out the top speed of a 68gt 390 with 325hp. If there is a statistic from Ford that would do find. Any of the automobile magizines would work as well.

I don't know of an official top speed, but when I was young and stupid I took my 390 '67 Cougar up past 140. Basically the same car. Not recommended, but possible. :-[

Go to this site and enter your tire size and gear ratio and it will give you a speed per RPM. That is not to say that you have the horsepower to reach a given speed with the weight of the car and the amount of drag you produce, but it will give you an idea.

http://www.mustangworks.com/analyzer.html

There is another tool that you can buy/try that sounds really cool!!!!! and will allow you to enter the vehicle weight, horses, grade, and wind to figure out exactly what your cars top speed is. I did not buy/try it but it is located here.

http://www.rapidline.com/calc/performance/pctopsp.htm

Although I personally wouldn't take a 35+ year old car past 100mph (unless it had all new suspension, brakes, etc...

The prototype "Lil Red" Shelby was lent to a writer for Road and Track for a weekend, and he took it up a hill past Riverside, CA, and was caught, and spent overnight in jail..

Anyway, he topped 140, limited only because the front began to lift up!! This pre-dates jellybean nosed cars. This was a 428CJ car with a Paxton blower, too! The cops had to open the hood to see what it had, too!

Paul.

:o

I am trying to find out the top speed of a 68gt 390 with 325hp. If there is a statistic from Ford that would do find. Any of the automobile magizines would work as well.


I know they will go 130 with a 3:50 differential, but that is past red line. Don't intend to do it again. These cars really hold the road.

It has alot to do with aerodynamics. Sure the engine in the right car will fly (F1 or IRL), but our vintage mustangs aren't the most aerodynamically efficient vehicles. To get a little more top speed requires an exponential amount more HP :o. Even the new 'stangs top out at about 140 unless they've been gone through. and they're much more aerodynamic then ours are. But I think that has more to do with the motors being held back than aerodynamics, thanks to safety engineers at Ford :-\. Our vintage iron is basically as aerodynamically efficient as a brick compared to the new cars :'(. I wonder how the new '05 Stang will do. ??? It looks sleek on the backside, but the front will be an inefficient "wall". Who cares though if they actually decide to put a V10 in the engine bay :o.