Jump to content
SAU Community

Recommended Posts

Just looking for some general feedback (and hopefully within the next 60 minutes) as to what people would think of the following.

I have a 1992 R32 GTR, and the tailshaft bearing needs replacing. The mechanic has asked me if id be interested in putting in a single piece tailshaft, as then I wouldnt have to worry about cv joints, centre tailshaft bearings etc.

My main concern with this is, talking to a few people, it would punish the rear diff a hell of alot more than it does currently.

What are peoples opinions on doing this?

Thanks

Nik

Link to comment
https://www.sau.com.au/forums/topic/39003-single-piece-tailshaft-on-gtr/
Share on other sites

Well, the original ones last for many years - and Nissan put the one that's in there, with a cv joint, for a reason. I am cannot understand why they would put a CV joint in a tail shaft for the hell of it, it would be cheaper and probably lighter to use one piece.

Can this mechanic guy give you a guarantee that a one piece wont fark anything up - and do it in writing?

I am always sceptical when a someone says they can do things better than the manufacturer, without having the R&D to support it.

I agree with Steve, Nissan put it there for a reason. Last year my mate put a one piece in his warm VL thinking it would eliminate the need for the centre bearing etc. The tailshaft was quite thick in the wall and it was balanced. Lasted around 6 months then let go at 210kmh, made a mess of the floor, stuffed the gearbox output shaft and also the diffs pinion gear. $3,000 later for floor and mechanical repairs. I know its a different car but the same principals apply, i remember touring car commodores raced with the centre bearing still in place.

Hi Nik

The problem you will encounter is this, the GTR does not have a spline shaft coming out the back of the box (ie: ford BW35, C4 & GM T350, T400, powerglide to name a few of the more common RWD) - it has a 4 bolt flange.

The spline actually moves in and out with the rear suspension (as these car are mostly live rear axle - I know this is kindergarten basics, but I have to make sure I'm explaining myself!!), where as the GTR has the diff centre mounted solidly to the rear cradle.

The trouble with putting a solid shaft into the GTR means you will have no movement between the rear of the box and the front of the diff flange. I would love to see how he is going to mount a solid shaft between the diff and box (which are both solid mounted, as on the normal falcs etc, you slide the tailshaft all the way into the back of the box, then bring it back to mate to the rear uni/flange on the diff)

So, unfortunatly in your case, the short answer is no (unless he is going to convert your rear box flange, to enable it to be the spline type - scary!!)

I looked at all of this only last night, as I finished bolting up my tailshaft.

One thing you need to look at is to make sure your current centre bearing has not come adrift of the lugs on the hoop mount. Remember I told you mine was fragged? when I looked at it, it had come out of the lugs - so now that it is back in - it is way tighter, very little movement.

Best of luck - let me know how it goes

Dan

i think you can on a rb25 as they arent solid bolted to the gearbox they slide in on a shaft if they do id say it would be cool... previous the vl is a very isolated incident a one piece shaft especially on lowered commodores is a good idea due to the agles a 2 piece creates from being lowered..

well i have a HR31 passage... Its RWD and has the IRS/LSD rear end. I am not too sure how it is mounted etc hence why i asked the question.

But having a think about it i can see how the 2 piece would work with the diff when it moves up and down.

I am nearing the stage where i'll need to get the yoke and tailshaft mated to each other, so this information is pretty valuable to me :D

the idea behind a 2 piece is to reduce driveline vibration put simply, one pieces also need more frequent maitnance, that is why 2 pieces are a more popular facory fitment.

i think another problem with such a conversion is that most one piece tailshaft setups use a extension housing with a stronger extension housing setup to support output shaft better, the centre cv bearing setup allows only minor horizontal in out movements whereas one piece will transmit more vertical and radial whip like forces to output shaft and housing. constantly chewed out ext housing seals are signs of this excesive radial movement.

Hey guys,

I received this email from a very helpful guy at Hardy Spicer. He raises some good points to consider:

It is not generally a good idea to replace a two piece shaft with a single piece shaft for two main reasons:

 

           1.         The geometry between the gearbox and diff are different for the two different shafts. Changing from one to the other requires changes to gearbox and axle mounts to obtain the correct geometry. A one piece shaft also requires more room than a two piece shaft and often there is insufficient clearance to fit a single piece shaft; even if the transmission tunnel is big enough to fit a one piece shaft there are often complications with seat belt anchors, hand brake brackets, cross-members, suspension mounts, exhaust(s), etc.

 

           2.         The main reason for using a two piece shaft is related to the speed that the shaft spins at. A one piece shaft has a much lower speed rating than a two piece shaft of the same length. Shafts in many applications can be spinning at up to 2000 RPM faster than engine speed due to overdrive ratios in top gear (sometimes the top 2 gears) and a single piece shaft simply can not handle the speeds required.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • The car/ECU will have all the sensor that it needs and expect to have. I think i do not have to explain to you how the Link is way better specialy if you have swapped engine   I just do not want to deal with any "problems" cuz i have only Nistune which i learned is not that great and in my case cant even deal with that speed problem (Link can) And of course it will be way more easier to tune and diagnose and safe. And for the ECU/speed problem...i dont know.
    • Per Mark Roberts of Sonictune: Mark Robert Author At this time, no. No ETA either 2016-17 models. You will be able to purchase and install a 2018.5+ TCU though   TCU purchasing and pricing info! As we near the release of TCU tuning, I am going to answer some questions I get asked often.   What do I need for TCU tuning? At this time, you will need a 2018.5+ TCU to be able to tune. If you have a 2016-to early 2018, you will need to replace your TCU with the newer version. One good way to know if your TCU is good is if you have auto upshift in manual mode in 1st gear around 6500 rpms. If your manual 1st gear goes to 7k rpm and will hit the rev limiter unless you shift, you have the older TCU.   Why do I need to buy another ecu license/phone flash if I already have it on my ECU tune? The TCU is its own computer module. It is completely separate from the ECU. Because of this, you will be required to purchase a TCU license and, if your tuner has it, the phone flash license required to tune it via phone/bluetooth.   Do I need TCU tuning? TCU tuning is NOT required. However, the faster your setup, the more it will assist in track and dragy time consistency.   If I’m ECU tuned by (tuner A) can I get my TCU tuned by (Tuner ? Yes, since it’s a different module and a completely separate flash, you can have two different tuners. However, it is highly recommend that you have both tuned by the same tuner. For me, my TCU tuning will directly complement my ECU tuning style and features and running my ECU and another TCU or vice versa MIGHT cause some issues. At this time and for the foreseeable future, I will only be tuning my current ECU tuned customers TCUs.     I have a SYVECS AWD controller. Do I still need it? Yes! The AWD controllers main job is to control your AWD system. However, with TCU tuning, you will no longer need the auto-shift function as that will be done through the TCU. The AWD controller will still be very beneficial for racers looking to maximize traction on the launch.     Shift schedule changes: holding gears longer at lower pedal input as well as max shift rpm changes. Please note, the new ECU race rom coming out will address 90% of the shitty drivability issues these cars have through custom maps from myself and Racebox—as well as others I am sure.   Increase shift speeds: as seen in the videos I’ve been posting, the TCU shifts much faster once tuned.   Increased shift pressures: as also seen in the videos, much firmer full throttle shifts.      
    • Per Mark Roberts of Sonictune:     Mark Robert Author At this time, no. No ETA either 2016-17 models. You will be able to purchase and install a 2018.5+ TCU though   TCU purchasing and pricing info! As we near the release of TCU tuning, I am going to answer some questions I get asked often.   What do I need for TCU tuning? At this time, you will need a 2018.5+ TCU to be able to tune. If you have a 2016-to early 2018, you will need to replace your TCU with the newer version. One good way to know if your TCU is good is if you have auto upshift in manual mode in 1st gear around 6500 rpms. If your manual 1st gear goes to 7k rpm and will hit the rev limiter unless you shift, you have the older TCU.   Why do I need to buy another ecu license/phone flash if I already have it on my ECU tune? The TCU is its own computer module. It is completely separate from the ECU. Because of this, you will be required to purchase a TCU license and, if your tuner has it, the phone flash license required to tune it via phone/bluetooth.   Do I need TCU tuning? TCU tuning is NOT required. However, the faster your setup, the more it will assist in track and dragy time consistency.   If I’m ECU tuned by (tuner A) can I get my TCU tuned by (Tuner ? Yes, since it’s a different module and a completely separate flash, you can have two different tuners. However, it is highly recommend that you have both tuned by the same tuner. For me, my TCU tuning will directly complement my ECU tuning style and features and running my ECU and another TCU or vice versa MIGHT cause some issues. At this time and for the foreseeable future, I will only be tuning my current ECU tuned customers TCUs.     I have a SYVECS AWD controller. Do I still need it? Yes! The AWD controllers main job is to control your AWD system. However, with TCU tuning, you will no longer need the auto-shift function as that will be done through the TCU. The AWD controller will still be very beneficial for racers looking to maximize traction on the launch.     Shift schedule changes: holding gears longer at lower pedal input as well as max shift rpm changes. Please note, the new ECU race rom coming out will address 90% of the shitty drivability issues these cars have through custom maps from myself and Racebox—as well as others I am sure.   Increase shift speeds: as seen in the videos I’ve been posting, the TCU shifts much faster once tuned.   Increased shift pressures: as also seen in the videos, much firmer full throttle shifts.      
    • The fancy pants red shock tower brace is finally incoming from MX5 Mania, getting it shipped from 'Merica has been a long and problematic process, and GWR, the 'Merican supplier will not ship directly to consumers outside of the US, Mania basically had to order a heap of them, the colour choice was silver, or red, and we all know anything red adds 5 killerwasps of dynotorques..... Whilst it does fit over a 2.5, and I've seen a few photos and videos of it being installed and fitting, google also says it might get real close to the FAB9 intake front runner, people in the US says it does fit with the FAB9 intake, except for one person who said it slightly touched.......so there is that.....LOL..... As it seems that I am the first in AU to have this combination of parts there's no local knowledge about fitment, so I'm just a willing guinea pig in this endeavour, I'll cross my fingers and toes and hope for the best In other news, I ordered stuff from China  on the same day I ordered the 23° silicone bend from Victoria, the stuff from China arrived a day ago, the 23° silicone bend is still travelling around Australia thanks to Australia Post, and "may" be here next week
    • Very good news...I contacted Racebox about it last night. My car is a 2016 so remains to be seen if it is compatible, requires a TCU swap, or is impossible.
×
×
  • Create New...