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Just wondering with people out there who have had to replace their old tailshaft. What did you replace it with?

Did you go 2 piece or 1 piece?

Custom or nissan?

Looks like I may need to replace my 5-6 month old 1 piece tailshaft. And I wanted to see what other people have done and who they went with.

Good or bad experiences.

Also What type of power are people putting out? Especially with the two piece stock tailshaft.

thanks

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Ring any tailshaft maker in your area and they should tell you that a tube shaft of the length required in a skyline (I think it's around 50inches) will go critical at 6000-6500rpm. The harmonic inbalance is usually so harsh that they bend or buckle as a result.

Of course it depends on the material they are made from, how thick and the diameter of the tube but 2 piece shafts are stronger, much stronger. We put 600+hp through them all the time without hassles

When I put the 25 box in my 32 I got a local place (Final Drive) to build me a new tailshaft, for $700 I got a 2.75" 2 piece to the length I needed, with a brand new slip yoke to suit the 25 box, heavy duty rebuildable Spicer uni's and a new centre bearing.

+11ty on the comments about 1-pieces in our cars, they might be fine in a Torana but not Skylines :P

Edited by bubba

i really want to understand why 2 piece is better than 1 piece - is it?

Its a harmonics thing. The one piece gets a death vibe at certain rpm whereas the 2 piece halves the likelihood of it happenning.

  • Nope 1

i really want to understand why 2 piece is better than 1 piece - is it?

Ring any tailshaft maker in your area and they should tell you that a tube shaft of the length required in a skyline (I think it's around 50inches) will go critical at 6000-6500rpm. The harmonic inbalance is usually so harsh that they bend or buckle as a result.

Of course it depends on the material they are made from, how thick and the diameter of the tube but 2 piece shafts are stronger, much stronger. We put 600+hp through them all the time without hassles

Just wondering with people out there who have had to replace their old tailshaft. What did you replace it with?

Did you go 2 piece or 1 piece?

Custom or nissan?

Looks like I may need to replace my 5-6 month old 1 piece tailshaft. And I wanted to see what other people have done and who they went with.

Good or bad experiences.

Also What type of power are people putting out? Especially with the two piece stock tailshaft.

thanks

you probably need a new cv joint at the rear.. alot of people dont realise that the 1 piece offerd by everyone re uses the 20 yr old cv.... albeit re packed, unless you get uni joints on the back... and a new cv is like 700 bucks or something.

i replaced my one with a ba-bf v8 falcon center cv joint. same inner spline and same bolt pcd. only thing is the body needs to be machined to suit the rear dif flange as it fits into it. rather than bolts to it only.

2 piece shafts are nicer to the car maker. drive line angles etc etc. also as said previously, the critical rpm at wich harmonics take over. 2 short shafts will not hum like a long single one.

im no engineer but i dont think the length of a gtr shaft will be an issue. the longest 1 piece in use is the oe ford falcon station wagon at 1.7m.. pre ba series. and its alloy.

The imbalance wouldnt have something to do with the independent diff centre being solid mounted, as opposed to older style vehicles where the centre can move up and down with the suspension thus helping to releive some of the imbalance would it?

traybak utes i have noticed also have 2 piece shafts, I started wondering why and my logic was that when you fully load them up there is not alot of rear suspension travel (they are basically designed so they can run on the bumpstops). If your engine/box is vibrating away but the diff is solid I figure this is where the harmonic imbalance could stem from..

Just another one of my homebaked theories.. :D

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