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#1 ·
I know the driveshaft is a two piece or three piece...whatever! My friend changed his in his GTO and what a difference to power to the wheels it made! Can we do this mod and what are the negatives to doing it? I am surprised to have not heard this question yet on here but maybe I missed it. Looking forward to the replies and answers! Thanks in advance!
 
#2 ·
You can have a custom driveshaft made. I don't know of any companys right now selling anything driveshaft related for the Vs. BMR used to have a one peice carbon fiber, but I beleive they said that they didn't sell any. So they discontinued it.
 
#3 ·
I am wondering why no one has done it and will it interfere with the independant suspension? I can't explain how much my friend said it did for more power!
 
#4 ·
Well one reason is that it's not cheap, and theres really not much power gain from it. It would help with driveline clunk, but that would also make the rearend see that much more abuse. Plus BMR stated that their shaft was to big to be used with the factory resonator, and while that doesn't bother everyone, it will hurt some of the sales. Add that to the already low number of Vs, and you don't have a very good business case.
 
#7 ·
I think I started a thread about this a month ago but do not recall the answers and reasons why a one piece driveshaft will not add power to the wheels? I would like to hear all the opinions on this please! I believe one guy commented about it not delivering much more, if any more power, to the ground! How can this be true as we are losing power to the ground from somewhere? My buddy put a one piece DS in his GTO and the Corvette Doctors, in N.Y., L.I. couldn't believe the numbers his car put to the ground and said it was because of his driveshaft! They did not do the work, he did it himself and just tuned the car there! Without getting to the numbers of his car and what he has done I would like all opinions on the driveshaft bit for the V! Thanks in advance!
 
#8 ·
I tell you i look at the driveshaft on the V and i could it believe all the stuff they connected to it. from the motor to the tran to the driveshaft their this rubber balancer it looks to me, they got three u-joints and thats just awaste of hp there. i think 3 u-joints.
 
#9 ·
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#10 ·
Uh, why not search for it. Especially since you started it. Should be easy to find.

On a side note, did your buddy dyno before and after the DS swap?

http://www.cadillacforums.com/forum...-forum/83481-driveshaft-change-anyone-do.html
UH, because there was not much reaction and my question was not really answered so, why look for it? But thank you for doin it! The reaction I did get was from one or two people and they claimed that it would not get a lot more power to the ground! I believe you stated that it was just too expensive and other than that, there was not a lot of reaction or answers so, I am trying it again! My friends car was not dynoed before and after as the DS was the first thing he changed and said he noticed a lot. The vette doctors dynoed it after quite a few mods and again, couldn't believe the numbers! They said that with his mods they expected 25-30hp less! His GTO has bolt-ons, which include headers, NO exhaust stock cats, and a cam and it dynoed at 422hp and 398 torque. The car runs well, trust me!
At any rate, I may be the guinea (sp.?) pig as I may get a great deal by a driveshaft shop to try it. I am debating on whether to do it or not with the feedback from you guys. I guess nobody has done it yet and that is surprising, I guess! I do not know what the great deal is yet as I will speak with him tomorrow, it was my friend who asked me if I wanted to do something like this and really didn't want to after the responses I got from the last thread! Then, I looked into more and I am deciding on trying it. I was more or less wondering:

Why we have this 3 piece driveshaft and what are the negatives to going to a one piece?
 
#11 ·
I beieve you will find as driveshaft length increases terminal speed decreases. Some of the "hotrod" trucks running around see issues now and then. It has to be one hell of a tough shaft to be long.
 
#12 ·
If you can get a deal try it. Maybe, you will start something. Like CHarris said, since it will be longer without support then it will need to be bigger in diameter, but I'm sure they will know that. Keep up informed.
 
#23 ·
After riding around with a Z06 clutch/flywheel combo for a while now, I'm pretty convinced that the parade clunk is in the stock flywheel. It's almost completely gone after the flywheel swap, and what little there is left is no worse than other manual transmission cars I've owned.
 
#14 · (Edited)
You might to redesign the exhaust system, it's up in there pretty tight and there's not much room, a one piece shaft will probably require more undercar clearance and the exhaust is dead in the way.
I would suspect that a one piece shaft would be slightly more efficient do to a difference in frictional losses of multiple joints and the play of a carrier bearing mount but it's going to be a trade off for ground clearance and other factors on a V.
 
#16 ·
You'll have to redesign the exhaust system, it's up in there pretty tight and there's not much room, a one piece shaft will require much more undercar clearance and the exhaust is dead in the way.
I would suspect that a one piece shaft would be slightly more efficient do to a difference in frictional losses of multiple joints and the play of a carrier bearing mount but it's going to be a trade off for ground clearance and other factors on a V.
Now, this is why I asked this question again because now I have many more answers! The driveshaft must be bigger you're sayin and it will need more clearance, the exhaust will have to move too, maybe! Sounds like a nightmare but I will call this guy and get more info. and get back to you guys ASAP! Thanks for the info. it's a lot of help!
 
#15 ·
The only way I can see it putting more power to the ground is by being lighter. Less mass to rotate...just like lighter wheels. Isn't there already a carbon fiber alternative out there?
 
#18 ·
All of this was stated in the other thread.
 
#22 ·
You must be awfully bored to be so into writing nothing everytime! It seems 1/2 the people believe it will be a difference and 1/2 think it is worthless! So, I want to know if I should do it given the fact that I need to send my shaft to the place for this to happen. I believe it has to make more HP to the wheels but what will be the negatives! So, the more feedback, the better and this is getting done for all us V owners as these guys say they would sell it for around $700, not the $1200 that someone stated! SO JON, DO YOU HAVE ANY OTHER RIDICULOUS POSTS TO SEND?
 
#21 ·
Ooops, LOL.
I forgot about the fact that the diff doesn't move.
I'll go back and change what I wrote to make sense.

Not sure why they don't use a one piece propshaft unless they use this one because of the CV joints on each end.
 
#24 ·
James also said his was much better after the flywheel change.
I haven't driven his lately.
He needs to take me to lunch for me to verify that it's better!
LOL
 
#27 ·
I might reiterate, this sounds like a lot of work for a negligable gain.
I'd almost be surprised if a dyno could even detect the difference.

My opinion would be that your friend in the GTO "feels the difference" to justify what he "feels in his wallet".
A lot of heavy duty applications that I have worked on have 2 piece shafts.
From an engineering standpoint, I am not sure what the benefits or drawbacks might be.

It seems to me that this forum would dry up if people weren't allowed to talk about things that have been brought up before.
I know I see the same topic pop up sometimes in 3 places at once.
 
#29 ·
I might reiterate, this sounds like a lot of work for a negligable gain.
I'd almost be surprised if a dyno could even detect the difference.

My opinion would be that your friend in the GTO "feels the difference" to justify what he "feels in his wallet".
A lot of heavy duty applications that I have worked on have 2 piece shafts.
From an engineering standpoint, I am not sure what the benefits or drawbacks might be.

It seems to me that this forum would dry up if people weren't allowed to talk about things that have been brought up before.
I know I see the same topic pop up sometimes in 3 places at once.
I had already described the negatives, that I know of, in an earlier post and that is the only thing holding me up from doing it!
With that said...you are a Cad Technician? Isn't it quite obvious that a one piece shaft will put more power to the ground and get rid of that slight hesitation that all two piece shafts have? I can also see that you read one part of a post and use that statement without reading the rest with your 'feels it in his wallet' RIDICULOUS statement! HE COULD HAVE RETURNED IT FOR A FULL REFUND! The vette doctors dynoed the car and have dynoed 6 other GTO's with much less gains and similar mods and their tune! You must also take us for idiots or a younger version of guys who have not had fast cars before, so you think we can't feel a difference? Between us, we have had 15-20 sport cars, fast cars, whatever and have worked on almost every one and street raced every one of them! So, please...SAVE IT FOR THE NEXT THREAD! There's internet racers and then there are INTERNET DRIVERS, I am sure you fit the latter! Have a great day...Willard!

P.S. I guess to get answers or opinions you must deal with some flack and it is understandable! I thank you all for your input and even these replies make me learn something! I'll keep you all posted on the driveshaft thing!
 
#28 ·
That's every internet forum.

I personally like an old subject being resurrected with a new thread occasionally. It gets all of the ideas on the first couple pages (instead of being mixed in with a bunch of chaff), as well as giving members who weren't around for the first thread a chance to pitch in their two cents.
 
#30 ·
I see that I need to take a moment to reply to clear up a few misunderstandings.

Yes I am a Cadillac Technician, some say I am pretty good but I try not to blow my own horn. That being said, bear in mind my training is to maintain GM cars and light trucks to factory specifications. I work in a dealership, not a speed shop where people modify factory systems for whatever reason. I never professed to know everything about this topic, nor any other in recent memory. I offer information that I know to help people, I sometimes speculate a little bit based on what I have seen and what my training and experience have taught me. Sometimes I make mistakes, sometimes I don't.

Regardless of how "rediculous" my statements are I really don't think it justifies, what I consider, the personal attack you launched on me in your last post. Perhaps my statement wasn't well thought out, but I don't recall saying anything about you, your friends, your car, your friends car that would indicate I thought anyone was an "idiot" or has never owned or worked on a performance vehicle.
I have yet to see you post anything difinitive to indicate that he actually gained rear wheel torque or horsepower by changing to a single piece shaft, maybe you did and I missed it. I don't doubt that it makes the car drive differently but to really understand the validity of his statements I'd like to see a before and after dyno test that shows a change to a single piece shaft made such a world of difference. I can't say much about a GTO because I have never been within 50 feet of one, but I am quite intimate with the workings of the CTS-V as many members of this board can attest to. I have worked on many of their vehicles with a seemingly high degree of satisfaction.

As you know a driveshaft is a metal tube with joints on each end (and sometimes in the middle) to transfer power from the transmissionto the differential. I can see where elminiating the center joint and carrier support might reduce frictional losses by a small amount but, having lived in the "show-me" state for 13 years I would just like to have someone explain to me why this would make such a "big" difference. I am completely open to an intelligent discussion on the topic, but I will be the first to profess that my expertise is more oriented to electrical and drivability issues than basic mechanical things.

To sum it up, my skills are honed to find out what is wrong with something and fix it, not speculate as to what changes might affect more rear wheel horsepower.
If you still REALLY believe that I was trying to insult you, your friend, or anyone on this forum, then I offer my apologies, it wasn't intended. Years of doing this sort of thing on the web has made me realize that it is very easy to read intent into printed words that just isn't there. It's happened to me before too.
I hope this clears up any misunderstandings about my intent or what I have said in this, or any other topic.

If anyone else has a problem with me or my statments please feel free to contact me privately so we can address those issues like men. I know how to use the "edit" button on my previous posts and don't have an issue doing it to clear up any such problems.

Otherwise, if it's okay with everyone, I'll continue to do what every member of this forum does.... express my opinion and make an occaisional mistake or two.
No hard feelings.
(BTW, you forgot to say something about my mom) :histeric:
 
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#34 · (Edited)
I see that I need to take a moment to reply to clear up a few misunderstandings.


If anyone else has a problem with me or my statments please feel free to contact me privately so we can address those issues like men. I know how to use the "edit" button on my previous posts and don't have an issue doing it to clear up any such problems.

Otherwise, if it's okay with everyone, I'll continue to do what every member of this forum does.... express my opinion and make an occaisional mistake or two.
No hard feelings.
(BTW, you forgot to say something about my mom) :histeric:
EWILL3RD: Nothing bad intended and I aplogize for flying off the handle a bit! Opinions are what this forum is for and sometimes words written can be taken wrong which has happened from time to time. It is not like actually chatting for most of us. I had a bad day yesterday and probably was an 'idiot'! Sorry for the confusion and Rick prolly just talked me out of even trying the shaft but I'll ponder over it the next couple days! Thanks for your input EWILL and it is always welcome!
P.S. Great last sentence!
 
#31 ·
I think one thing is true of any car company- they are in business to make a profit. If for some reason an item is not necessary for the car to function they would not put it on if it costs more money IE the two piece drive shaft is probably more expensive than a one piece. Perhaps though, a one piece by virtue of the increased length would be more expensive than a two peice due to better materials/precision balance requirements. Unless we could talk to the engineer that worked on this part of the drive train every thing is just a guess. It would rock if some of these engineers would post here, they could clear up a lot of issues (yeh, we did this this way because of this). A switch to a one piece drive shaft could be the greatest thing or a complete waste. When someone does it and tells us about it then we will know. That is the greatest thing about these forums, every one can learn from a few people who have taken the, if you will, first step!
 
#33 ·
Why not a one-piece shaft? Some things to ponder:

1. Tunnel/component clearance - As mentioned previously, there's only so much room to work with on the V.

2. A long one-piece shaft will be more susceptible to whip, vibrations and shear.

3. Crash energy management - Telescoping multi-piece shafts absorb energy from backward engine movements in a frontal crash or forward engine movement in a rear crash.

4. I'm sure there's other stuff; I didn't stay at a Holiday Inn express last night.

With a one piece shaft, it would be prudent to add an adequate driveshaft hoop for safety. A broken one-piece shaft can be deadly whipping around under (through!) the car.

Shaft length, diameter, material, type/design of joints on either end, etc. of a one-piece shaft are critical. Get any of the design elements wrong through shadetree engineering and the downside may not be pretty. Sure it can be overbuilt but that's just bad engineering when it doesn't need to be.

If you want to know the details on the how's and why's, order this --> Universal Joint and Driveshaft Design Manual

Spending money on a driveshaft would be low on my list unless it were a serious weak link in the driveline compared to the torque capacity of the other components. There is always one part of a driveline that is the weakest link. Would one rather replace an expensive component such as a transmission or a relatively more cost effective propshaft?

Our GM friends do visit. Show these sometimes "strangers" on the forums a little respect and we may get more inside information. The wolf pack is strong here when wound up on the "truth" as they see it.

If one is looking for more power, do the things that get more fuel and air into the engine such as heads, camshafts, superchargers, turbos, etc.

And in closing, the things engineers wrestle with everyday - There is no free lunch, everything has trade-offs. It's the rule of the universe as we know it.
 
#35 ·
I'd say that the negatives far outweigh any potential gains. The only real gain I can even imagine from swapping to a solid driveshaft would be reducing torque reversal in the driveline (eliminating clunk), which could only be considered a "cosmetic" mod since you aren't getting more power to the ground. Your friend's power most likely came from the tuning they did at the 'Vette shop.

My $.02 ? Look elsewhere for power improvements. If you want less clunk, get a Z06 flywheel.
 
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