wallace

Just received my new shaft, no adapter flange.

AWSOME new Billet Pinion, direct bolt in.
This thing only weighs 16pds.

Gigantor

What did the oem weigh?

wallace

OEM 2 piece shaft weight is a whooping 38pds.

Thats's where rotational mass kills torque, HP. the car really gets moving now.
The clunkyness is all but gone from the drivetrain.
This is easily one of my best seat-o-pants mods for sure.

rriddle3

You're wanting to save weight, right? Then you should remove the rear seat, passenger seat, spare tire, stereo, get smaller diameter forged wheels...do you see where I'm going? If you like and want the aluminum shaft that's fine and dandy, but any significant weight savings that will translate into actual performance increases (not just butt dyno estimations) is going to require lots of removals and/or substitutions.

wallace

Riddle, you're free to remove anything you want from your ride.
I like mine the way I want it. I paid for it!
I'm not asking for suggestions, simply posting about the driveshaft.
If you don't like the thread, don't post in it bro.

05gtowner

THIS IS NOT DONE TO REDUCE WEIGHT. IT IS DONE TO REDUCE DRAG ON THE DRIVETRAIN. This mod reduced drive train drag and free up hp that is lost through parasitic loss. The reduction of 20 pounds of more from the 2 piece driveshaft and replacing it with one that is less that half the weight of the original increases acceleration and reduces the rotational mass you get as well as the clunk associated with the 2 piece driveshaft. The same can be done for the accessory drive on the engine itself. Steeda for example make great under drive pulleys to reduce the parasitic loss of over spinning the accessories on the 3V engine. Same effect. REDUCING PARASITIC LOSS. You arent gaining hp just freeing it up.

rriddle3

Well, somebody is touchy, aren't they? Sorry if I invaded your private thread...oh,wait...it was posted in a forum, so it's open to discussion. That's the way internet forums work.

Womprat

Girls, girls, you're both pretty..

SoFlaBoss

Riddle, Based on your first response, you miss the whole point of this thread, nor do you understand the benefits of a light one-piece drive shaft.

Getportfolio

I'm thinking about picking one up. How will it affect a tuned car?

cdynaco

There is no clunk with the factory 2 piece driveshaft. Quit spreading false information.

From a Ford engineer on the Bullitt program that used to post here about this same worn out false rumor:

s_____:
Clunk is driven by total driveline lash, dominated by the gear sets and clutch tuning/capability. The 3.73 amplifies this a bit compared to the 3.31 and 3.55 axles. The 2-piece driveshaft is not the cause of the clunk noise. The Bullitt will have higher levels of clunk compared to the base GT. The base GT throttle response is a bit softer than the Bullitt's. The increased throttle response makes the clunk a bit easier to get. It is a trade-off - improved performance feel vs clunk.

s_____:
The post mentions high speed and 160mph - The Mustang (as it leaves AAI) is speed limited well below that for a reason. Like I said before, I do not know specifics about the dynotech piece, what it does or does not do. I do know about the 2-piece in the factory car. It is a fairly robust piece. Vibration is not an issue unless the centerbearing shims are not installed properly, the shaft has a balance issue or the pinion angle is off. These would be quality issues (that I'm not aware of having in production), not design. The 2-pc has no roll in whether or not you have a random vibration. U-joint angles, run-out (flange or shaft), balance and system modal (resonance) response govern vibration.
****************************

s_____:
The 2-piece driveshaft is required to meet internal engineering requirements for safe operation at max vehicle speed. Basically, it is designed to provide a driveline system resonance well above what the speed limiter will allow you to operate at. If you put your driveline into resonance, bad things may happen! I've seen what it does to a car and it isn't pretty.

The driveshaft CV joints are required components on this type of driveshaft when combined with a live axle. If the rear suspension were IRS, simple flex couplings would be used (look at the new Camaro, Challenger, etc...) and would make for a lighter driveshaft.

The driveshaft also has an internal torsional damper (ITD) which is solely there to attenuate axle whine. If package allowed, the ITD would be mounted on the exterior of the driveshaft as a much lighter ring design. Since the equivalent inertia is required out of the smaller diameter part when installed inside the driveshaft, the mass has to increase. So, you get a heavier ITD vs a lightweight ETD.

A single piece steel or aluminum 1-piece would have to be larger in diameter than the current package allows. Basically, you would have contact with the fuel tank at full rear suspension jounce. 1-piece carbon fiber was explored at one time...

Hope this helps.

s_____:
I would not assume an aftermarket piece "solves" a problem. Yes, you can stuff a massive driveshaft into the tunnel but it will not meet standard vehicle engineering requirements. Our requirements take many factors into account, with the biggest one being your personal safety under a wide variety of operating conditions. Our parts are engineered to work in one big system. Aftermarket parts are generally not engineered. By this, I mean that they are designed to fit properly (usually) and improve one or two attributes specific to your application.

For example, if you want a lighter weight driveshaft that gives you less rotating inertia, you can buy this aluminum 1-pc driveshaft. But, that's all you get - lighter weight. Not proven durability, safety (how does the driveshaft react in a rear impact?, clearance to other parts like the fuel tank?), NVH, ride (driveshaft plunge force actually affects your ride quality), etc...

But that's the great part about it being your car. You get to decide what you want your Mustang to be. Just be cautious and think about how these parts may affect the rest of your driving experience, safety and wallet if it breaks or breaks something else in the car.

I've been in your shoes (which is why I became an engineer and worked my way onto the Mustang team!) and know exactly where you are coming from, though. I don't know specifics about the d/s you are referring to but I'm just giving you some things to think about and consider.

Thanks for buying a Bullitt!

2011GB/CS

I put one on my car last year and it is a very nice piece.

wallace

indeed!
My ride definitely feels smoother.

Hey 2011GB/CS, I see in your sig you own a Mini Cooper S.
Nice ride, I just recently sold my 04 liquid yellow.

05gtowner

First off I am not spreading anything. I am simply relaying my experiences so unless you drove my vehicle before and after you don't know what you are talking about. What you requoted as gear lash most of the rest of the mustang owners will call a 'clunk' and it was much reduced or GONE after I installed the lighter one piece driveshaft. Plus something that weighs that much less then the factory 38 pound piece is going to have that much less of an effect on the 'gear lash' because there is less spinning inertia present to cause a 'clunk' or whatever in the trans or rear diff. The "clunk' may not come directly from the 2 piece shaft but it certainly is accentuated or exacerbated by it. I have done this mod with my car with ABSOLUTELY NO OTHER DRIVE TRAIN MODIFICATIONS AND THE AUDIBLE CLUNK WAS GONE. In many other cases of owners there's was also reduced or gone as well. There was no vibration at highway to 120+ mph either. I am sure there is a reason ford used (safety reasons) it but I am sure optimized all out high performance wasn't the reason. Bottom line is if you want faster acceleration, less noise in the drivetrain and lighter weight then this is a good way of doing it. Not to mention any quality driveshaft manufacturer is testing and rating their products at or above what you are likely to run it at. As far as durability goes most of the driveshaft companies have been making these shafts since late 05' early 06' so i don't think durability is an issue. Heck mine has been on for longer then the factory unit it replaced was on that took a dump at the bearing and the stealership wanted $1200 to replace.

cdynaco

Believe me, I'll trust a Ford engineer over you all day long. Any 'clunk' is NOT from the factory piece. It is a well engineered component designed to fit in a complete system.

Yours is not engineered to fit in a complete system. Its just an after market alum drive shaft. A guy on another thread is already reporting that his alum 1 piece is hitting his fuel tank.

You make it sound like Ford never had it on a rack, or a track, just slapped some shoddy piece in that is barely thrown together, and approved it for 151 mph.

.

05gtowner

You can trust whomever you like but I won't drink your kool-aid and never asked you to drink mine. I trust my experience in the real world with real products. Not theory or something tested for a relatively brief period before its release. This thing has several YEARS of real world testing on my vehicle and has proven itself as being a quality piece. It isn't just a "after market alum driveshaft" it is an improvement. I don't know what you have against the after market but if your all mighty Ford trust the after market vendors such as Steeda and hurst just to name a few then I think we can trust them too. In fact I think ford actively participates in the technology sharing program with steeda. And stop trying to put words in my mouth. I never said the Factory unit was a "shoddy piece barely thrown together" I said "I am sure there is a reason ford used (safety reasons) it but I am sure optimized all out high performance wasn't the reason" Which i believe is true. You are free to believe whatever you would like. It is still for the time being a free country. But let me ask you this, are you going off of what some engineer said or are you basing your knowledge on experience. HAVE YOU EVER EVEN INSTALLED OR USED A QUALITY ONE PIECE DRIVE SHAFT IN YOUR CAR? If not then you are just typing because you like the reading what your write. You don't have a leg to stand on. I am telling you from using both the OE unit and a "after market" unit which one was better for ME and MY car. I could care less if you believe me or not. I will sleep like a prince either way.

Oh and BTW I checked out your pictures of your bullitt. Beautiful car. However, now I know why you are so dead set on quoting and believing one of MANY engineers who worked for ford/bullitt project says. Other then the fact that (if he is who he claims to be) he has knowledge but I think a bigger reason is you have a invested your ego into it. Because if he is wrong you are somehow wrong. Believe me I get it. But considering that the same engineers who built your bullitt also installed essentially a block off plate http://www.imboc.com/forums/showthre...exhaust+secret and here http://www.imboc.com/forums/showthread.php?t=168430 in the H-pipe to give your bullitt its movie sound proves that they had other motives other then all out performance. My point is car manufactures make sacrifices that are sometimes not in the best interest of a gear head and someone wanting to wring out all the performance out of a particular system. They do it because they have to abide by such strict fuel, safety, cost and manufacturing protocol. They don't want to come out and say what you bought isn't the best. It is just advertising. Brilliant picture btw. I am sure that was a real hoot taking it at 150mph while driving one handed.

Getportfolio

Not to jump in this but I've only heard of V6 DS fail at high speeds and V8 DS fail with blatant misuse.

People always tell me the GT DS is fine... It's the V6 one that is crap. I wish some V6 members could share their experience.

SoFlaBoss

The OE two-piece driveshaft absolutely clunks. However, from my experience you usually can't detect it until after replacing the OE UCA and LCAs with aftermarket pieces. If you ever have the opportunity to inspect an OE two-piece driveshaft, preferably a new one or one with low mileage, you'll hear it clunk just by just twisting it by hand. I don't care what the engineers say.

wallace

Trust!?
It has little to do with trust!
Of course Ford's engineer are going to say that!
I wouldn't expect anything less from ford or any other car company.

If they (car company) came on an open forum posting about its inadequacies it would
Create quite a stir. maybe even a recall, lemon law.

But I don't care about any of that.
My clunk is considerably deminished and that was a bonus.

cdynaco

Quote:

Originally Posted by 05gtowner

Wow. That's just too whacked. Why are you so wound up?
There is no take up in the joint of the 2 piece. I have well over 500,000 miles in Ford SRA's with 3.73's. The sound is from the diff - not the shaft. What little clunk I hear in Bullitt occasionally on my dirt road from the ranch to the highway, is the same sound I've been hearing for 30+ years in Ford SRA's. It is somewhat magnified because Bullitt got the GT500KR diff. Hell, it's prob stronger than my F150 4x diff.
That engineer, and another one, conversed for quite awhile here on numerous threads. The threads were lost in the crash. I only saved a small portion to file. Dis them if you want, but you weren't here. From the convo's you could tell they weren't pushing some company line. They were genuinely answering a wide number of questions as engineers that actually designed and worked on the S197 team - not defending an agenda, but explaining why they chose to do certain things. It was very interesting. They handled many questions about specific mods - and they were modders themselves.
They often stressed that the components are designed as part of a system where safety and function - across the entire range of performance and in a number of different circumstances - were key. You haven't done any of that. Your 1 piece is not part of that system. You just went to the store, bought something, and bolted it in. And now are going crazy because engineer's countered your false story about the 2 piece being faulty. Pray you don't get rear ended. Don't go fast on rough roads so you don't hit full jounce.
I didn't take the pic.

Lemon law?