Does anyone have a really good explanation as to why my ´92 cally T has a transfer box with the small exit shaft - which is normally only found on cars with the C20NE 8 valver according to the EPC?
Well one obvious explanation could of course be that some previous owner had a TXB fault and changed it to the wrong type. Question is, if the TXB is in fact an 8v one or just a Turbo one with the smaller shaft?
Your assumption is probably correct, it is most likely an 8v TXB. Supported by 'why would someone fit an 8v prop shaft front to a turbo box' and 'the coupling is part of the viscous coupling, which means it would have to have been split to get it fitted' - possible, but unlikely.
This can be further confirmed by the serial number stamped on the TXB. If it is a turbo it starts with a 'Y'.
Now the not so good news, if it is an 8v TXB then the viscous coupling will deliver less than the max 90 NM to the prop shaft. This means less drive to the rear wheels. It also means that if you drive it hard enough you will be experiencing more front wheel spin than normal, which equals more than usual heat in the viscous coupling, which is most undesireable.
To top it off, of course, the 16v & turbo variants had the larger prop coupling for the very reason that more power is delivered, so in your case the safety margin has been reduced.
Well it´s probably a good thing that I have a spare TXB then.... with the big propshaft and all!
Is the TXB serial number visible with the TXB installed on the car?
I know for certain that it´s the small propshaft, because when we changed the clutch I had bought the dust cap for the propshaft - and it was too big. However, the new dustcap did fit on my spare TXB. Pity then that we decided to now swap TXB´s at that time, eh?
Well for starters I´ll hook up a temp sensor and a SPA gauge to monitor the TXB temperature. That was kindof the plan anyways. That way I´ll get an alarm if the temperature gets too high.
As for not driving it hard - well, thus far I haven´t had any problems and not even a hint of wheelspin. Of course the definition of "driving hard" varies from person to person, but I suppose I´d better monitor my gauge on track days, that´s for sure.