The Mustang Forum for Track Enthusiasts

Track Mustangs Online was built specifically for those who track their Mustangs!

GT350 Carbon Fiber Drive Shaft Options

Tob

TMO Race
206
65
Upstate
You sometimes have to call but I suspect that the difference in price is due to the CJ's listing not having an SFI rating sticker on it. I purchased mine through LMR and paid the additional for the sticker.

The QA1 piece is very well engineered. Be sure to carefully inspect the shaft upon delivery as the packaging QA1 is using isn't the most robust. The first shaft I had delivered was in a box completely torn open and hanging out the end. QA1 took care of me upon notification.

Just a suggestion, measure your driveline angles on the new shaft. I used an online calculator from Spicer and would be happy to compare data.
http://spicerparts.com/calculators/driveline-operating-angle-calculator

x20170916_173105.jpg


x20170917_190003.jpg
 

ShelbyGT350_17

TMO Beginner
You sometimes have to call but I suspect that the difference in price is due to the CJ's listing not having an SFI rating sticker on it. I purchased mine through LMR and paid the additional for the sticker.

The QA1 piece is very well engineered. Be sure to carefully inspect the shaft upon delivery as the packaging QA1 is using isn't the most robust. The first shaft I had delivered was in a box completely torn open and hanging out the end. QA1 took care of me upon notification.

Just a suggestion, measure your driveline angles on the new shaft. I used an online calculator from Spicer and would be happy to compare data.
http://spicerparts.com/calculators/driveline-operating-angle-calculator

x20170916_173105.jpg


x20170917_190003.jpg
Can you tell us the weight of each? to make up the difference in LBS? How do you like it? Do you feel any difference, less vibrations? Was the install easy?
Thanks! great pictures!!
Rogelio
 

Tob

TMO Race
206
65
Upstate
Can you tell us the weight of each? to make up the difference in LBS? How do you like it? Do you feel any difference, less vibrations? Was the install easy?
Thanks! great pictures!!
Rogelio
OEM two-piece steel shaft is ~31lbs and QA1 CF shaft is ~21 lbs. The difference in feel is subtle but definitely noticeable. It is very smooth throughout the range. I do have a very faint harmonic from about 47-52 mph in any gear and at any rpm. It was there before and the shaft didn't eliminate it.

The install isn't complicated at all. You do have to pay attention to the instructions as the front bolts and washers are color coded as the assembly was balanced in a specific orientation. QA1 does this instead of trying to bond or fasten any type of balance weight to the shaft.
 

ShelbyGT350_17

TMO Beginner
OEM two-piece steel shaft is ~31lbs and QA1 CF shaft is ~21 lbs. The difference in feel is subtle but definitely noticeable. It is very smooth throughout the range. I do have a very faint harmonic from about 47-52 mph in any gear and at any rpm. It was there before and the shaft didn't eliminate it.

The install isn't complicated at all. You do have to pay attention to the instructions as the front bolts and washers are color coded as the assembly was balanced in a specific orientation. QA1 does this instead of trying to bond or fasten any type of balance weight to the shaft.

Thanks for the great info!
 
  • Like
Reactions: Tob

blacksheep-1

TMO Addict
2,466
1,969
Do yourself a favor and inspect that shaft often, I personally am not a fan of CF driveshafts because road debris and other garbage can chip away at the outer coating, then water, oil and whatever can get into the the layers, weakening it. They obviously work well, but that is their Achilles heal. The good news is that if you get a ding in it, you can usually find some clear paint and fill it in...sort of the way helos use duct tape on their CF rotor blades..sorta..whatever. But I bet it does make a big difference, I just prefer aluminum.
 

ShelbyGT350_17

TMO Beginner
Do yourself a favor and inspect that shaft often, I personally am not a fan of CF driveshafts because road debris and other garbage can chip away at the outer coating, then water, oil and whatever can get into the the layers, weakening it. They obviously work well, but that is their Achilles heal. The good news is that if you get a ding in it, you can usually find some clear paint and fill it in...sort of the way helos use duct tape on their CF rotor blades..sorta..whatever. But I bet it does make a big difference, I just prefer aluminum.
Very good points, thanks for all the information, will look further into it, do you know of any good sources for Aluminum shafts?
 

GT350 Junky

TMO Intermediate
16
3
California
Hey Guys -

Since I have my driveshaft out of the car at the moment I am going to order a QA1 CF replacement. Is it necessary to pay the extra $100 for the SFI Approved?

Thanks.
 

Tob

TMO Race
206
65
Upstate
I personally am not a fan of CF driveshafts because road debris and other garbage can chip away at the outer coating, then water, oil and whatever can get into the the layers, weakening it. They obviously work well, but that is their Achilles heal.
Everyone pondered the same thing when the 13/14 GT500 was released. Oddly enough, this has not proven to be the case. Far from it. And with respect to the QA1 shaft in a GT350, it is better protected than S197 factory iterations due to the positioning of the exhaust system. In other words, I wouldn't worry about but it never hurts to be on the lookout.

Hey Guys -

Since I have my driveshaft out of the car at the moment I am going to order a QA1 CF replacement. Is it necessary to pay the extra $100 for the SFI Approved?

Thanks.
No. The shafts are 100% the same in terms of construction with or without the certification sticker.
 

GT350 Junky

TMO Intermediate
16
3
California
Everyone pondered the same thing when the 13/14 GT500 was released. Oddly enough, this has not proven to be the case. Far from it. And with respect to the QA1 shaft in a GT350, it is better protected than S197 factory iterations due to the positioning of the exhaust system. In other words, I wouldn't worry about but it never hurts to be on the lookout.



No. The shafts are 100% the same in terms of construction with or without the certification sticker.
That is what I figured but wanted to check. Thanks for the reply!
 
  • Like
Reactions: Tob

GT350 Junky

TMO Intermediate
16
3
California
Anyone using a driveshaft loop with their CF driveshaft? If so, Which one?

I got mine installed today but before I put it back together I wanted to see if you guys are using loops.

Thanks!
 

Gary Smith

TMO Intermediate
21
35
Berkeley, CA
My goal with a DS upgrade is to have my car come off of corners a bit quicker. If a lighter DS will help me exit corners a bit quicker I'll be happy.
I'm wondering what the argument is that a lighter driveshaft can noticeably improve acceleration? Without attempting any real analysis, my thought is that the rotational inertia of the driveshaft is insignificant compared to that of the wheels.
 

TMSBOSS

Epic Contributor
5,268
2,215
Illinois
HPDE
5-10 Years
I'm wondering what the argument is that a lighter driveshaft can noticeably improve acceleration? Without attempting any real analysis, my thought is that the rotational inertia of the driveshaft is insignificant compared to that of the wheels.
Agree for the 550 platform. On the 197s we gained significantly. The stock shaft was two piece with a Bearing and joint near the center. We dropped near 20 LBS. total. The lighter shaft combined with the loss of slop associated with the additional joint and bearing made a noticeable difference.
 

VoodooBoss

Rick
Moderator
I'm wondering what the argument is that a lighter driveshaft can noticeably improve acceleration? Without attempting any real analysis, my thought is that the rotational inertia of the driveshaft is insignificant compared to that of the wheels.
Note I said "if". The wheels are what they are so they don't change. I'm running a wheel/tire package that is 10 lbs per wheel lighter than stock so that gain is already locked in. If the DS is lighter than stock it should respond similarly to a lightened flywheel. Regardless it's been determined the CF DS is only about 10 lbs lighter than stock. I'd still buy a CF DS but I doubt there would be any noticeable performance gains.
 

TMO Supporting Vendors

Top