Citroen XM Forum

Eddie nuff wrote:Or just slap a HDi box in it and drive lazy.

Problem there Neil is bell house to block match, im trying to find out if the 2.5 box's and PRV blocks use the same patten...

The thing with the HDi 110 5th gar is its tooo long for the PRV 24v HIGH end power... the box is tuned for low down torque

Yeah . . . and it's l-o-v-e-l-y

Easy enough to sort if not totally rotten...

Just wondering whether a cable change arrangement could be retrofitted to PRV gearbox with a bit of thought? Wouldn't that make things a lot smoother? I remember the first 2.5 I bought after having a 2.1, first time I drove it I was astounded by the smoothness of gearstick.

You'll need a whole 2.5 to get the cables off and if you do it would be worth cleaning them out and grading them up as best you can

marc61 wrote:Just wondering whether a cable change arrangement could be retrofitted to PRV gearbox with a bit of thought? Wouldn't that make things a lot smoother? I remember the first 2.5 I bought after having a 2.1, first time I drove it I was astounded by the smoothness of gearstick.

Its like going from a 1.9 td xantia to a hdi 110 with cables..

but the boxs are very different and mounting brackets needed for the cables which clamp them at the same time and where the gear change levers are on the back of the 2.1 gearbox the 2.5s change spigots are on the upper side of the box and in quite different places.. I good idea in theroy but not in practice by a long way.

HDi boxes are 18 spline centres against 21 spline for the MG5.

John

Ooo that reminds me too the input shaft overall on a hdi box is larger in diameter then the 2.1 cable change box.

For interest Paul, I learned something recently on my CX regarding the feel of clutch/gearchange action. The CX gearchange isn't good by design and the clutch/cable arrangement isn't particularly smooth either. I got a heavy duty clutch from Helix based on a Cosworth clutch with a Citroen spline and it's so light and smooth it's almost unbelievable, as good as a 2.5 hydraulic clutch. Its quite remarkable for a cable driven clutch and its transmitting a serious amount of torque, grips like mad. So the clutch cover springs and the release bearing action has been optimised so the action felt on the pedal is really smooth. I thought that was only achievable with a hydraulic clutch previously.

The CX gearchange remains the same, a bit too mechanical as no smooth cable action, but the driving experience is much nicer. I don't know if they do a clutch for a PRV engine but if I still owned one and it needed a clutch change I'd seriously look at getting a Helix clutch.

Cheers

Marc

Just out of interest, Marc, have you ever tried running a CX (or other clunky) gearbox on one of the more recent 'box lubricants - eg Castrol Syntrax, Syntrans, or one of the other Manual Transmission Fluids ? These were developed to get over the problems of ZF and other boxes being notchy, or difficult to engage or shift, particularly in cold weather, and are a manual-shift version of ATF. I've used them many times.