Smike

Big thanks to Force-Fed Performance out of Fayetteville, NC. Guys over there and at Epic Motorsports are top notch. My work keeps me traveling. I had found out I was needed on another assignment right when the drive shaft and safety loop came in. Guys said, "No problem. Parts are here. Come on in." Hard to beat the customer service. They fit me in. And helped with the testing. If you are in the Fayetteville, NC area - it is worth it to give the Force-Fed Performance guys a call!



The biggest gripe I had with the v6 Mustang was Fords decision to use a lower quality drive shaft and limit the car to 115 mph. Rather than using the GT drive shaft. Which from a manufacturing standpoint is a bit strange. The v6/GT/Cobra all share transmissions and rear-ends. Why not share the part in-between?



Old v. New:


The Shaftmasters Aluminum v6 drive shaft is a high quality piece. And 10lbs lighter than the OE unit. Thats 10lbs less rotational mass. Can't complain about that.



For the testing we used 3rd gear. Car has no limiters now. I was not comfortable using 4th for the drive shaft testing given it takes the car to 130mph. And after seeing a few failures already. For before and after tests 3rd was used.

Peak whp/wtq was unchanged, however, a gain of 8 whp/wtq was achieved across the power-curve. I was honestly surprised. Not expecting to gain that much power from the new drive shaft. This modification was for my own safety and track days.



Final pulls after we did the before and after testing, using 4th gear, showed the car makes 273 whp and 252 wtq on this Mustang Dyno. Force-Fed has tested a car on their dyno then drove over and tested the car again on another area shops DynoJet and found a 12% correction factor (Mustang reads lower). 273x1.12= 305.76 whp and 252x1.12= 282.24wtq in DynoJet terms.



Basing off Motor Trends dyno testing at K&Ns DynoJet (found here).

Taking the 4th gear numbers from my pulls and factoring in the 15% powertrain loss that Motor Trend used - 352 bhp and 325 btq. Gains over stock of around 44 horsepower and 38 torques. Impressive for minimal modifications.

Video:
http://www.youtube.com/watch?v=wvXYzUh8UYA

Very impressed with the v6 motor.

Cheers,
MG

beaustang

That is unbelievable! And on a Mustang Dyno to boot! Slap a Procharger on it and make 400+ HP and really surprise some S197 GT guys!

Smike

Oh, already in talks with Procharger to do the SC on this motor

Alec

Very cool. I also never understood the idea behind the sub-par driveshafts these cars come with. You would think a 305hp Mustang would come with a driveshaft capable of more than 115mph

smokinAMD

The driveshaft isn't the reason the car is limited to 115. That would be tires.

Alec

A weak DS that's known to grenade around ~118 doesn't help either

DarkhelmetRT

That doesn't make alot of sense to me. It seems the driveshaft would see it's greatest load at the moment of take off when your trying to overcome inertia. I would think that he load difference between 80mph and 120mph would be minimal at best. If I'm wrong, please explain why.

Smike

Base tires:
Goodyear Wrangler SR-A S Rated: 112
Pirelli PZero Nero All Season W Rated: 168

67B:
Pirelli PZero Z/Y Rated: 186

Only the base-base model comes with the S rated tires. Not the top selling package. I have never seen a 2011 on the Goodyear base tires.

Its been a problem with Ford for a long time. The police Crown Vic had the same issue with the drive shaft (and it came with police issued hi-performance tires). Fords fix - impose a limit on the car. ECU programming is cheaper than drive shaft quality control.

This is also a fleet car (rental). There are likely multiple reasons why it has the limiter.

We know this, there have been failures. The drive shafts cannot handle high speeds. My contacts within Ford have been tight lipped about it. I knew about the DS before buying the car.

This mod was well on my list before buying the car.

I saw no weights for balancing on the OE unit. The issue is not launching, its speed the unit can rotate at. All failures have been at speed. From the photos I have seen, its been the area where the ribs are; ironically, for strength, that have twisted apart. There might be subtle weight variations within those ribs. Just enough to cause a frequency within the drive shaft at high rotational speeds for it to come apart.

Not a fan of that design. Too many ways for there to be variations in the drive shaft. Its a super easy install. Not a lot of money. Any future issue fixed.

hogasswild

Which DS did you get? I see two listed, one for up to 500hp (4") and one for up to 750hp (3.5").

2005Redfire6

That one looks like a 3.5 to me! I wanna say if I remember correctly my 4" driveshaft was bigger then my stock one... Those look about the same size in diameter.