[kennygunit]

I was wondering how fast i would be able to go with a 1969 ford mustang, 302. Just a coupe. I was taking it about 90 on the freeway, and it felt like i could go a little more, but the RPM's sounded a little high.

Its a stock engine with no modifications.

[Print Dad]

Hello Kenny,
Boy am I gonna take heat for this one but as a dad I gptta post.

What's the rush? - 80 is plenty fast. Remember you are driving a car that is 30 years old. That means worn suspension, brakes, tires could be an issue etc etc.. It only takes a second to cause permanent damage to your motor or yourself.

The car probably would go faster but why bother. If my son was going over 90 I'd take his car.

Now done with the lecture....The size of the rear-end gears will allow different top end speeds.
But your car should not be pushed unless it is modified in many ways to do so.
The motor is telling you something...I am old and don't want to go too much faster;

I really hate sounding real old.....but perhaps other will think about what I have said as well.

Trust me ..... been there....done that......Be Carefull...... Print Dad

[kennygunit]

yea, i was late for work. It was a newly paved freeway, and a big straight away, so the conditions were pretty safe. Its the only time i had gone that fast. I was just curious.

Thank for the concern though Print Dad!

[blea9082]

Hi! PrintDad has a good point. About 40,000 of our fellow Americans die on the highway EVERY YEAR! Don't be one. Take you car to a track if you want to experiment with speed.

I'm assuming your coupe has an auto trans. If so, it is very unlikely that you can really hurt the engine by driving it fast. It won't over-rev itself. But like PrintDad says, the rear-end gear will govern the top end. You probably have something around a 3.25:1. With a 302 tuned up well, the coupe could see 100 - 105. Going downhill with a tailwind, maybe 110.

[Sick467]

Here's a neat link to theoretically determine the speeds of your car at different RPM, Gear Ratios, & Tire Sizes. You'll have to do some home work. Things to find out...

Your rear diff ratio.
Rear tire size.
Your tranny gear ratios.
And your Redline RPM.

Enjoy - I've had alot of fun with it trying to determine my new diff ratio and tire sizes.

Speed/RPM Calculator

[67ragtopStang]

I agree with somewhere in 100 -110 range, but why push a 40 year old car that hard. You are apt to damage/kill the engine, if you push it too hard. The higher the RPM's, the more heat generated and the more wear on the engine. Ever wonder why racers rebuild/replace their engines so often?

I used to drive very fast when I was 19, but it was in relatively new Corvettes (both my brothers had Vettes) and my Mom's Ex Police Car. These cars had better suspensions & brakes than other cars in that era.

If you want your Mustang to be fast and perform more like a newer car, you'll need to do a lot upgrades to the engine, transmission, brakes, steering, rearend and suspension. Lots of $$$$!!