Custom carbon fiber driveshaft

[Red65]

Did you know that QA1 gets 10% of their driveshafts returned? TEN percent..... 1/10 have more than .020" run out.. Stock shaft has been mid 8's numerous times. Just need an aluminum version with the strength of OEM, but only about 5-7lbs lighter for under $900, and they would be the most ideal shaft ever made.

I have a hard time believing that at face value. QA1 is one of only 9 driveshaft shops that are SFI 43.1 Certified. Not only that, they allegedly spin up each shaft to ensure harmonic balance out of the box. If 10% of them were bad, I'd have a hard time seeing them pass certification and it would surely be noticeable on their end. They do say that when installing, it's best to test drive with the yokes clocked 180-degrees both ways to see which lower's NVH, which is entirely normal for driveshafts (especially for IRS cars). If customers have an issue with their QA1 vibrating even after clocking the yokes both ways, I would question either the runout of the differential flange, or even if the differential is located properly. We have seen stock bushing cars have the differential shift after hard launches and the mounting points of the diff ending up off center of the bushing. It's entirely possible that alone would cause problems with 1-piece shafts that the factory 2-piece shaft masks.

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[Cory S]

I have a hard time believing that at face value. QA1 is one of only 9 driveshaft shops that are SFI 43.1 Certified. Not only that, they allegedly spin up each shaft to ensure harmonic balance out of the box. If 10% of them were bad, I'd have a hard time seeing them pass certification and it would surely be noticeable on their end. They do say that when installing, it's best to test drive with the yokes clocked 180-degrees both ways to see which lower's NVH, which is entirely normal for driveshafts (especially for IRS cars). If customers have an issue with their QA1 vibrating even after clocking the yokes both ways, I would question either the runout of the differential flange, or even if the differential is located properly. We have seen stock bushing cars have the differential shift after hard launches and the mounting points of the diff ending up off center of the bushing. It's entirely possible that alone would cause problems with 1-piece shafts that the factory 2-piece shaft masks.

All I know is he tried everything he could. Then he measure the run out and found .022" out. He spoke with tech numerous times. He finally asked how many they get back, and they said around 10%. There's a reason why Ford felt like a 2-piece was needed on the S550, and why they haven't produced an aftermarket upgraded piece.

 

[Red65]

All I know is he tried everything he could. Then he measure the run out and found .022" out. He spoke with tech numerous times. He finally asked how many they get back, and they said around 10%. There's a reason why Ford felt like a 2-piece was needed on the S550, and why they haven't produced an aftermarket upgraded piece.

Granted, the 2-piece design is somewhat necessary due to the reasons stated above about how long the DS is on the MT82 since it doesn't have a traditional tail housing. But still, I am inclined to think that a lot of the supposed DS issues we see with our cars is due to problems with runout at the flange. Being a mass production car, there's a LOT of allowed variability in driveline parts. That is also a reason why 2-piece shafts are a benefit for Ford. But being that QA1 is specialized in individual parts rather than the car as a whole, and that they have to abide by specific certifications for competition and safety reasons, they have a lot less leniency on the variance that's allowed in manufacturing their parts. What I wish we had was a direct comparison of your buddy's driveshaft between measuring the runout on the car (how I assume he did it) vs on a certified driveshaft balancer.

 

[LSchicago]

All I know is he tried everything he could. Then he measure the run out and found .022" out. He spoke with tech numerous times. He finally asked how many they get back, and they said around 10%. There's a reason why Ford felt like a 2-piece was needed on the S550, and why they haven't produced an aftermarket upgraded piece.

My stocker was in up to about 850RW, just swapped it out for a DSS aluminum before my last pulley change.

 

[Angrey]

Granted, the 2-piece design is somewhat necessary due to the reasons stated above about how long the DS is on the MT82 since it doesn't have a traditional tail housing. But still, I am inclined to think that a lot of the supposed DS issues we see with our cars is due to problems with runout at the flange. Being a mass production car, there's a LOT of allowed variability in driveline parts. That is also a reason why 2-piece shafts are a benefit for Ford. But being that QA1 is specialized in individual parts rather than the car as a whole, and that they have to abide by specific certifications for competition and safety reasons, they have a lot less leniency on the variance that's allowed in manufacturing their parts. What I wish we had was a direct comparison of your buddy's driveshaft between measuring the runout on the car (how I assume he did it) vs on a certified driveshaft balancer.

A good number of driveshaft vibration issues aren't the shaft. Shafts get sent back and "re balanced" only to find out there's nothing wrong with the shaft.

1/2 critical speed and offsetting angles makeup a good number of "I just installed this driveshaft and now my car shakes at xxx speed."

Our cars aren't the greatest in terms of adjustability in that respect. How many guys simply slap a driveshaft on and never even check the angles?

The problem is made MUCH worse or amplified due to the length of the shaft. A 2 piece shaft has stubby shafts that can take a zillion rpm before they vibrate so the 2 piece masks or soaks up disparity with the offsets, especially with CV intermediate joints and end joint.

 

[Angrey]

The other aspect here is that Ford doesn't care about "us." They're building cars for the average consumer. A 2 piece shaft makes complete sense. It's cheaper, much less exacting and much more forgiving and even though it's heavier, in some cases, they may even take joy in that. The GT350 for example has weighted dampeners on the exhaust and 12 lbs of useless dampening on the 3160 rear to help soak up NVH. The 2 piece heavier steel shaft might actually be a benefit in that regard.

 

[Excelerater]

I added a QA1 CF driveshaft to my 2015 GT a few weeks ago. Its a well made unit and went in easily.

Ill shed some light onto the subject
First off its totally not noticeable driving around town or on the HWY,it does not add any power
or gains for a daily driver so if you are expecting some drama look elsewhere.

Where I did feel a difference is when I wacked the throttle and dropped down a gear and roll raced on the hwy,I def noticed more hit in the seat ,again it was not dramatic but every little bit helps .

If I was drag racing its a better option than the OEM unit (stronger,lighter) but if you are like me
and like to buzz up on the hwy and streets ,eehhh I may spend the cash elsewhere depending on what your car needs,there are a few suspension mods that I would rather suggest that did a lot of bang for the buck for my car than a shaft but my car has everything you can add under it already so I had to spend some coin somewhere this spring..

As for those who mentioned a two piece alum shaft,thats just silly . Bite the bullet and buy a alum one piece

There are a few brands out there I would avoid because they are vibration tubes,QA1 is not one of them,its the best you can buy right now

 

[Flyhalf]

great review. I agree 100%. my usage is for track only.. and im looking for that...extra kick you mentioned...
thanks again

I added a QA1 CF driveshaft to my 2015 GT a few weeks ago. Its a well made unit and went in easily.

Ill shed some light onto the subject
First off its totally not noticeable driving around town or on the HWY,it does not add any power
or gains for a daily driver so if you are expecting some drama look elsewhere.

Where I did feel a difference is when I wacked the throttle and dropped down a gear and roll raced on the hwy,I def noticed more hit in the seat ,again it was not dramatic but every little bit helps .

If I was drag racing its a better option than the OEM unit (stronger,lighter) but if you are like me
and like to buzz up on the hwy and streets ,eehhh I may spend the cash elsewhere depending on what your car needs,there are a few suspension mods that I would rather suggest that did a lot of bang for the buck for my car than a shaft but my car has everything you can add under it already so I had to spend some coin somewhere this spring..

As for those who mentioned a two piece alum shaft,thats just silly . Bite the bullet and buy a alum one piece

There are a few brands out there I would avoid because they are vibration tubes,QA1 is not one of them,its the best you can buy right now

 

[NGOT8R]

 

[NGOT8R]

I like the look and weight savings of a CF driveshaft, but after seeing Stephanie’s (from AM) disintegrate on the drag strip, that made me cringe. That’s the reason I would lean toward aluminum over CF. Fast fwd to 5:30 seconds to see the failure.

 

[Flyhalf]

I like the look and weight savings of a CF driveshaft, but after seeing Stephanie’s (from AM) disintegrate on the drag strip, that made me cringe. That’s the reason I would lean toward aluminum over CF. Fast fwd to 5:30 seconds to see the failure.

As always It depends..
Technically FROM THE BUILDER and how u mount.
A CF is also technically safer cause is disintegrate rather than aluminum that twist and turn destroying transmission and diff...

 

[Angrey]

I like the look and weight savings of a CF driveshaft, but after seeing Stephanie’s (from AM) disintegrate on the drag strip, that made me cringe. That’s the reason I would lean toward aluminum over CF. Fast fwd to 5:30 seconds to see the failure.

Couldn't tell which CF shaft it was. And the difference is that when CF fails, it shreds. When alloy fails, it clubs your car to death before you get it shut down.

There are CF shafts on the market that are stronger than AL shafts.

 

[drive_55_not]

A good number of driveshaft vibration issues aren't the shaft. Shafts get sent back and "re balanced" only to find out there's nothing wrong with the shaft.

1/2 critical speed and offsetting angles makeup a good number of "I just installed this driveshaft and now my car shakes at xxx speed."

Our cars aren't the greatest in terms of adjustability in that respect. How many guys simply slap a driveshaft on and never even check the angles?

The problem is made MUCH worse or amplified due to the length of the shaft. A 2 piece shaft has stubby shafts that can take a zillion rpm before they vibrate so the 2 piece masks or soaks up disparity with the offsets, especially with CV intermediate joints and end joint.

After fighting DS vibrations on my S197 all those years ago, I figured out pinion angle is less important than getting the correct length on the DS so the slip joint or CV aren't being pulled apart or compressed which is what caused a massive vibration on that car when I installed a Shaftmasters DS.

Fought that for a couple months til my BIL and I finally started checking alignment spec's after installing lowering springs and saw the wheel base was 105.9" instead of the factory 107.1.

I installed adjustable control arms to move the axle back to the 107.1" wheelbase and 95% of the vibration I was getting disappeared.

Granted the S550 diff is attached to the frame so the distance between the tranny and carrier should be fixed but there could be some differences in length from manufacturing/assembly of the body and DS.


As for a 2 piece aftermarket DS, I'm sure Mark Williams can make you one, But be prepared for some sticker shock.


And that was a DSS CF that exploded in that video.


.

 

[Red65]

I'm going to wager and say that the girl probably dumped the clutch on a set of radials. Carbon fiber driveshafts have historically been able to hold a lot of torque, but you can break almost anything if you don't launch properly.

 

[NGOT8R]

Does anyone know if the 15-17 GT manual transmission driveshafts will fit the 18+ GT? I realize that the flange on the transmission output shaft would need to be changed to a 15-17, but what about the differential flange? I ask this because this would open the door to more driveshaft options for 18+ cars and not limit them to only a couple of manufacturers.

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