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I'm about to make a one piece tailshaft for a 32 gtst with a gtr box (converted to rwd) and std 32 gtst diff that's making 500rwhp.

The GTR flange uses 75mm OD pipe( where its welded), while the 32 diff flange uses 65mm OD pipe (where it's welded).

What diameter pipe is best suited? any bigger than 3" pipe would have clearance issues.

How thick does the pipe have to be for this kind of power?

And whats the best method of stepping down the diameter of the pipe to suit the smaller R32 gtst diff flange?

A pic explains it clearer, currently using a shortened RB20 tailshaft.

th_tailshaft-shorten2.jpg

th_tailshaft-shorten1.jpg

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^^ 2 pieces are generally smoother driving.

don't try and make a tailshaft yourself. people who do will charge like a wounded bull but if the balance isn't perfect then you're in for trouble. tailshaft turns at 4 x wheel speed (roughly).

Have a custom 3" Gibson single piece with extra heavy duty uni's in my 31. Standard 4.11 Auto diff, RB20DET with a 25 box. Havnt looked back, after killing 2 sets of uni's and centre bearing.

Get one made up for you. Cant remember how much it was, but its definately worth it.

Also had clearance issues once we dumped it. Had the chassis rails 80mm off the ground, & the driveshaft was eating the handbrake cable bracket. Had to raise the car up about 40-50mm. Still chews into the bracket occasionally with extra passanger weight..

Easy, slide the 65mm shaft into the 75mm shaft, simply find what gauge sheet steel you need to wrap around the 65mm so its a snug fit. Make sure the unis line up as factory (if it has unis) bead of weld and you are done. Make sure the 75mm shaft is cut to the right length so the weld is at the flange. then get it balanced by a shop.

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