cool mine should be alright then

Guys, I spent 7 years doing driveshaft builds and mods, so here are the answers to some urban myths. Now I dont have a lot of model-specific data, just the basic facts.
Driveshafts are meant to be the weak link, it is the cheapest and easiest part to replace.
Horsepower/torque will not break a tailshaft in the middle, that is caused by critical speed failures. This is why V8 Supercars run a two piece tail-shaft, not because of horsepower. Some still use stock Commodore centre bearing/CV joint assemblies.
The alloy shafts in Falcons are lined with cardboard to stop the echo/noise inside them. This causes them to be heavy, and have a similar critical speed to steel.
The double-wall tailshafts are actually two separate pieces, one front piece welded to the front yoke only, and a rear piece slightly smaller diameter, welded to the rear yoke. These are then bonded together with rubber. It is to stop a harmonic noise in the drivetrain. They will fail after time, when the rubber perishes, and high torque/horsepower can tear the rubber apart.
The harmonic balancer-looking thingy on some gearbox slip yokes is just that, a harmonic bancer. When it fails, it can be removed, the tailshaft balanced properly, and all is good.
A good 3.5" diameter, 0.083" wall thickness driveshaft is good for HUGE horsepower, and will withstand about 7000rpm TAILSHAFT speed.
The cheapest/easiest way to fit a two-piece shaft is to get the centre out of a V8 commode shaft, and use that. A decent driveshaft shop can build the rest of the shaft for not a lot of $$$.
Hope this helps.

Sooty you are kinda close on the alloy driveshaft's but the 3.25" driveshafts normally have a cardboard deadner to stop ringing and a tuned steel deadner to absorb diff noise (the steel deadner makes up the weight along with slip yoke dampner if fitted). Now the 3.75" have foam deadners but these are normally used in the utes from BA onwards. The alloy driveshafts from the B series wagons wont fit into an E series sedan as they are simply too long. The alloy driveshafts handle high speeds better than the steel as they are lighter and have less flexing causing imbalance and petential failure. Ford also uses a 2 piece driveshaft with a centre CVJ in the XR6T and XR8 utes along with the FPV utes. The very early 2 piece ute driveshafts (BA series 1) had a CVJ on the rear along with an adaptor to fit the 4 bolt diff flange that is used on most E series. So if one of these drivehafts can be found its just a matter of shortening the rear and fabricating a mount for the centre bearing to suit an E series sedan. But there are different models that have slip flanges to fit either the 4sp BTR or T5 transmissions. The later ones only had the slip flanges for the T5 or a flex coupling that bolts to the 4 or 6 speed auto.

I have built and fitted two piece tailshafts to a wide range of cars to combat driveline vibrations at speed as well as these being essential for lowered cars. Most two piece tailshafts will cost $990 and they come complete ready to fit and include a centre bearing mount

 

 

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^^^Nice, location and web address please
Brett

My web site is www.malwoodauto.com.au and my email address is malwood@bigpond.net.au
The photo I showed was of a two piece tailshaft in an ED with an AU 6 cylinder and our T56 close ratio 6 speed fitted, this car also uses our under dash hydraulic setup.
Regards, Mal Wood

My email address is www.malwoodauto.com.au my email address is malwood@bigpond.net.au
The photo shows our two piece tailshaft fitted to an ED with our T56 6 speed fitted.
Regards, Mal Wood

We have the Ford one piece tailshaft guys wanting two piece (like me) and the the Holden two piece guys wanting a one piece.

So Mal what centre bearing did you use in that ED setup.
I was reading up on the AU Arrow Ford and the article indicated they used a two piece with a F350 cente bearing.

I am looking for a 500rwkw setup for a ED Ford with Borg Warner diff and a tremec up front.

I would think a F350 centre bearing setup to be pretty stout.



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This applies to Commodores

The factory 50mm diameter two-piece tailshaft – the design relying on rubber mounts instead of u-joints which go a long way to contributing to axle tramp, are notorious for failure when placed under duress.

BMR heavy duty alloy driveshaft’s are one-piece, are equipped with forged 1350 series uni-joints, cryogenically frozen front yokes and custom machined 300M billet pinion yoke adaptors. The factory Commodore driveshaft is the weakest part of the entire driveline.

Capable of handling 750 kilowatts.

NOTE: Due to the physical size of this driveshaft, the factory exhaust may require some modification. Most aftermarket exhausts tested do not have clearance issues. Driveshaft needs additional spacer if using Harrop Differential cover.