So it seems I was too quick to reccomend PST tailshafts as mine has unforunately failed. The carbon and ally tubes have separated, giving all the symptoms of a failed clutch. There is no visible breakage but there is a very loud screech/vibration that resonates through the bellhousing when the clutch is engaged under load. I can only conclude that sustained heat has caused the resins used in the bonding process to melt. There does seem to be some residue on the shaft. The slippage described is actually visible, I will try and get a video up in the next couple of days. Unfortunately for me this leaves the car decomissioned on a trip to QLD while I wait for a new one piece to get made up. I have emailed PST to see what they have to say. So yeah, as far as I'm concerned PST can no longer be considered the "good" c/f option. I would only consider chrome molly or steel for a replacement.
carbon and aly have different expansion rates so its only a matter of time before they fail. my ol girls rx8 failed after 2.5 years. i would go for a molly replacement. i think they are smaller diameter to so lesser rotating mass
Hey Rob when you get your new steel or C/R shaft made up, maybe you can ask UAS if they want to make some sort catch loop for these one piece tailshafts as a safety measure? I'll be in for a group buy.
There is alreadya bent sheet steel cross bar under the drive shaft from Stock. Dont know if its big enough but it is there.
Definately heat related and failure occured at the gearbox end of the shaft. That said if it was fit for purpose you would think it should hande the heat. My dumps are HPC coated and the factory heat shield is in place. Maybe heat wrap would have helped but it's a bit of a bandaid fix. I emailed PST on Monday night our time but no response yet.
Hey Rob your exhaust runs closer to the tailshaft than mine You have the custom exhaust that runs in the tunnel close to the box and shaft? Could this be the problem?
Yeah maybe but the dumps/cats are well forward of the tailshaft. The x pipe sits under the rear of the gearbox so it's not like the shaft is exposed to all of the seriously hot stuff... I think it is the ten hour drive (Syd to Brisbane) that did it, but not like it was under sustained boosting or anything. It would get hotter with a few hard laps I am sure. Got a steel one piece in there now and no issues for the drive home. I had a quick chat to my neighbour tonight who is an aircraft engineer and he was very surprised that they would bond c/f to alloy without using pins or something solid to secure it. I'm not sure what the PST process is, still have the shaft so I will have a better look in the morning. But yeah he did mention that without a fastening system it wouldn't last... I'm hoping PST get back to me, I sent a pretty straightforward email explaining what had happened and will they fix or repair it if I return it to them.
it looks like the xpipe is right under shaft where its bonded to the ally ? heat rises so will probably get hotter than you think..
i would be asking for a full refund. no way i would run another CF shaft after seeing what has happened. im more than happy with my 1piece steel unit
Your centre muffler is very close to the front, maybe move it back to get a little more airflow over it. Would be alot of heat build up at the muffler there.
Understand what you are saying re heat and also comments from black beast. Really though I shouldn't have to compromise my exhaust setup if the tailshaft was up to the job....
I guess it might be a draw back of a carbon shaft. Be interesting to hear what PST have to say about it.
