well....

i have been looking through c&l site and saw thier dyno sheets and it turned out that the stock mustang actually have 257 hp at the rear wheels and all this time i was thinking my mustang is burning some true 300 hp power.....

so is it true that my mustang is 257 hp on the rear wheels ?




my brother told me getting an aluminum drive shaft will reduce the miss timing between the motor and the rear wheel is it true ? if it is true is it a great advance for my mustangs power ?

thanks...

i ask alot so that i can know alot hehe

 

The 300 hp figure is crank hp, not rwhp - all manufacturers report crank hp because it sells cars - rwhp should be like 12-15% lower.

No two dyno's are exactly the same, which is why you can't look at absolute numbers like that. A car that sees 257 on one dyno may show 275 on another. Running your car on a dyno before and then after making modifications should give you an idea of how much hp the modifications added.

 

If I am not mistaken, you need to divide the HP numbers by 0.85. The factory numbers of 300HP are at the crank. The dyno is at the rear wheels. To equalize the loss of power through the drivetrain you need to perform the division. With a 257 rear wheel HP divided by 0.85, HP at the crank is 302. Hope this helps.

 

daaamnnn thats really a huge loss oh hp ....... and what about that aluminum drive shaft i asked about ? will it help prevent the loss of hp ?

 

automatic transmissions "absorb" more power than manual trans equipped cars, so they will dyno a little bit lower than the stick cars.

I would say that on the dyno sheet you posted that those would be very good numbers because the temp and humidity are low which yeilds the best numbers....it's also probably a stick car.

 

Best rule of thumb for figuring your drivetrain loss... (for fords anyways) 16% for Manual Transmission, 22% for Automatic Transmission.... and an aluminum driveshaft will only lighten your car (stock ones are H*E*A*V*Y)

 

aluminum driveshafts do free up power. especially in the new mustangs since the stock shaft is 40lbs+. anytime you can lose 30lbs of rotating weigh you are going to notice a power increase to the wheels. FYI non believers: track tested on my car .2 second faster with an aluminum driveshaft. the more power an engine makes the less difference it will make on the track since the engine has enough to compensate for the additional weight. it is a good mod to do as one of your first especially if you plan on staying n/a.