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J

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I read the thread from Feb. about the broken drive shaft on the Dyno, and I know he had a Manual Tranny. But, since we have a similar crappy, and heavy steel 2 part drive shaft on our Autos I'm thinkin' this may be my next mod to get a lightweight 1 piece aluminum shaft. The Shaftmasters page says their '11 GT is a true direct bolt in, it doesn't say that for the V6 drive shaft. So... the only driveshaft I change was on my '03 Honda Pilot OEM to OEM. What am I looking at besides purchase price for the driveshaft to get that thing installed? Then the safety loop in the middle also? OR, is there a better deal out there than Shaftmasters? They are always out of stock... so I'm thinking they are selling quite a few maybe. The links on the old thread no longer worked, so any experience and knowledge out there would be appreciated!!!
 

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Shaftmasters is $525 right now, very good deal.

You shouldn't need anything else to install it.

If you get a loop it doesn't go in the middle, goes right up front.
 
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Shaftmasters is $525 right now, very good deal.

You shouldn't need anything else to install it.

If you get a loop it doesn't go in the middle, goes right up front.
The loop on my Pilot is towards the middle, but it's a 2 piece shaft. See, that's why I ask these questions. And I saw the 524.99 price, but the not a "Direct Bolt In" thing still bugs me. I emailed the company, so they should get back to me during the week, but I was hoping someone on here already accomplished this mod and could fill me in.
 

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Sounds great and all, but would you really believe that the car would have a 9hp and 5tq gain from having 8lbs less weight?? I mean....really? I know it's rotating mass and not dead weight, but that seems more than realistic. Not to mention the dyno graph is well up into the 400's for hp. The safety feature alone makes it worth it, but I couldn't help to wonder.
 

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Sounds great and all, but would you really believe that the car would have a 9hp and 5tq gain from having 8lbs less weight?? I mean....really? I know it's rotating mass and not dead weight, but that seems more than realistic. Not to mention the dyno graph is well up into the 400's for hp. The safety feature alone makes it worth it, but I couldn't help to wonder.
I'm a mechanical engineer, I made a quick MATLAB model to figure out what is going on. The combined effect of reduced dead weight and rotating inertia is equivelent to about 1 HP unless my model is screwed up.
 

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Sounds great and all, but would you really believe that the car would have a 9hp and 5tq gain from having 8lbs less weight?? I mean....really? I know it's rotating mass and not dead weight, but that seems more than realistic. Not to mention the dyno graph is well up into the 400's for hp. The safety feature alone makes it worth it, but I couldn't help to wonder.
The dyno curve is up in the 400's for a good reason, it is the first ProCharged 2011 Mustang V6. It puts 461 HP down to the ground.

And yes, I do fully believe the HP numbers achieved with the driveshaft swap.

You will see similar effects when swapping to an aluminum flywheel, this is one of the next mods to this car.
 
J

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Yep, I believe it too. Losing that rotating mass is huge! Not to mention the safety benefit! Not an Engineer, but an Aircraft mechanic for the last 24 years.
 

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And yes, I do fully believe the HP numbers achieved with the driveshaft swap.

You will see similar effects when swapping to an aluminum flywheel, this is one of the next mods to this car.
An aluminum flywheel is worth so much more 'apparent horsepower' because the radius of the mass is much larger and because the motor accelerates so much faster than the drive train through the first few gears.

Also, I have drag raced an automatic car up to 22 runs in a night and have made a pile of time slips as thick as a phone book with said car. In the real world, it’s easy for trap speed to vary by 1-2 MPH for 'identical' runs. In the math, 1 MPH is equivalent to about 7 HP. So I'm going to continue to discount this dyno run as within the noise floor of repeatability for the car itself.

Also, I hope everyone can understand that the rotating inertia of the drive shaft accelerates relatively slowly in the real world, going from 0 to 4200 RPM (0-105 MPH for the car) in 13.7 seconds is a snails pace, even accounting for how a car accelerates faster at low speeds due to gearing.
 
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Ditto Joenpb. And kuddos to your 1/4 mile timeslip phonebook. I don't really believe the claim of .21 reduction in 1/4 mile time claimed by the company, specially in a V6 with only 350HP. But those who have done the swap say they do notice a signifigant change, and improvements on their dyno sheets as well. Car and Driver just did a test a couple months ago, using lighter wheels. Going from lightweight 15' wheels, then using the same wheel but increasing diameter and therfore more weight. Everytime they gained even 12 or 14 oz. per wheel they were getting noticably slower times, and braking distances increased. Would like to see a nonbiased test done on driveshafts too.
 

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Doesn't really matter whether the HP increase is 1 HP or 7 HP or what. The real reason for changing is the safety issue, and it never hurts to lose the weight.
 
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shaftmasters response

Jeff,
Our V6 shafts are also "Direct Bolt In". The V6 uses 4 bolt flanges at both ends, unlike the GT's that use a 6 bolt "CV" style head at the rear. Many shaft manufacturers use an "adapter plate" or "replacement pinion flange" at the rear. Our GT "Direct Bolt In" bolts directly to the 6 bolt OEM pinion flange, thus making it the only True Direct Bolt In on the market. All V6 shafts on the market are a Direct Bolt In shaft, including ours.
We do not sell safety loops, many Mustang owners use a safety loop that is made by BMR Fabrication.
Thanks, David

This is very good to know.
 

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I believe the numbers. I did the driveshaft swap before I did my supercharger and it was noticeable.
 

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So does Shaftmasters make one for the Auto's yet?
 

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I have the Shaftmasters driveshaft for the 2011,12 3.7 Auto with about 600 miles on it before I sold my 3.7 and got a 2012 5.0. Ship to your house for $370, If interested e-mail.
 

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I have the Shaftmasters driveshaft for the 2011,12 3.7 Auto with about 600 miles on it before I sold my 3.7 and got a 2012 5.0. Ship to your house for $370, If interested e-mail.
Dang. Someone is getting the hook up on this deal. Jump on this!!!
 

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I know, a dumb question - but what are the safety benefits for going to the aluminum driveshaft?
 
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