danzcool

Thanks, I knew something was missing something because the numbers weren't high enough.
So double the power will get you to double the speed on a dyno, but it's going to take 4 times more power than that to do it in the actual world.

So reversing the 650 for 180 MPH it takes about 81HP to go 90 MPH in an average car.

Norm Peterson

I'd ignore any mph claims based on any of the common dyno runs. They are only measuring torque and rpm. To dyno-test for top speed you'd have to program the resistance to increase as (roughly) a function of wheel rpm squared and specifically fit the resistance curve to each car tested.

At best, the dyno testing I've seen only accounts for rolling drag of the drive axle tires (as a deduction from RWT that you don't even see), and rolling drag increases only a little as speed rises.


Norm

CaptainRon

The 2011+ V6 is capable of hitting mid 140's, if you really want your car to safely run at those speeds then I suggest leaving your 2:73 rear alone. You want your sustained rpm to be between 3500-4500rpm. You replace that 2:73 with anything higher and your RPM will go up dramatically and gas mileage and high speed mph will suffer big time. My buddies '09 Roush 427 has 4:11 gears and maxes out at 147mph at nearly redlining the engine...
What I would change are the rear lower control arms, I would suggest the GT500's LCA's. They are stamped steel, will last longer than machined aluminum. upgrade your rims & tires, just get a set of 18" or 19" GT wheels/tires from craigs list.

replace your front springs with BR3Z-5310-M from Ford racing and get GT front struts & rear shocks. leave the rear springs alone. What the tires/front springs/dampeners are going to do is to prevent any kind of wander you are going to encounter at speeds higher than 100mph especially with the tall stock economy tires. If you have a rear spoiler, then your fine, even the little deck lid spoiler works great.
Dont worry about the driveshaft too much, all it takes is one or two people on these forusm to post something and it gets blown waaay out of proportion but if your really worried and cant afford a new shaft then at least install a driveshaft loop.


now realistically what i would do is replace your 2:73 with a 3:31 and just do some parking lot autocrossing and have fun...

venzbasco@gmail.com

My top speed is 145mph 3.55 gear with Bama performance tune and aluminum drive shaft from AM..this v6 mustang 3.7 is accelerate harder with tune and gear 3.55 ratio..it blasssst to drive completely different from stock..i raced with 2015 g37 infiniti v6 at the freeway i smoked the infiniti..So i recomend to all v6 3.7 mustang owners to replace your drive shaft to aluminum to reach your higher top speed 145mhp . Its really woth it..we are driving mustang the real muscle car..wake up your v6 and kick some bmw 3series..believe me this mustang v6 3.7 is fast and real muscle car..