gear changes

[simon down]

Hi

I sprint my 1st series fulvia coupe and have encountered a problem changing into 3rd from 2nd exiting faster corners under heavy lateral loads. This has meant me holding revs for longer or changing earlier to avoid the problem. Given the short period of time I spend on the track this is irritating rather than a real problem, but it obviously has an effect on the times I am able to get. The gearbox was refurbished 4 years ago (new bushes etc.) and thats how old the engine/gearbox mountings are. I am guessing that its a problem with flex in the mountings which means they need replacing. If this is the problem, can they be replaced without removing the engine/gearbox?

Any suggestions would be welcome

Simon

[1,6 HF]

If the engine and gearbox mounts were indeed replaced when the box was rebuilt, I'd be very surprised if they're your problem. Even with the occasional track day, they should last far longer than 4 years. When the box was rebuilt, were all the shift forks straightened? If not, they could be contributing to the problem.

But if it's really a flexing problem, I'd suspect the subframe mounts before I'd suspect the engine/gearbox mounts.

Johnny Keppelman may have some useful thoughts on this.

[simon down]

Hi

Thanks for this. Either way it seem like quite a big job to investigate (gearbox off or sub frame off), given the problem is not stopping enjoyment of the car for 99% of its usage. Probably something I will leave until something more major fails. I am intending to build up a spare sub frame/running gear anyway in the next year or so.

The gear stick doesn't seem to wave around excessively (not that I'm looking you'll understand!) so maybe the gearbox is at fault: this was only rebushed rather than thoroughly overhauled. Subframe mounts have polyurathane bushes in them, so this seems unlikely.

All the best

Simon

[ncundy]

If it is subframe mounts it is likely to be the metalwork in the rear mounts (under you feet) rather than the actual bush itself - even so I find it difficult to believe that it would cause problems with gear change, as that would suggest either flexing of the 'box casing or of one of the selector shafts and/or fork or the main lay shaft, neither of which I have heard of or felt in 20 odd years of Fulvia ownership.

A strange one ?

[1,6 HF]

I/m not at all convinced that it's flexing. If it is, then the subframe would be more likely than the engine/gearbox mounts (as the latter are not very old). But if the subframe has poly bushings, it's not likely the subframe. So I keep coming back to an internal gearbox issue.

[KeppelmanJ]

the flexing seems unlikely to me in any of the mountings, at least, and I don't see why it would effect shifting anyway. You may be wracking the subframe with cornering stresses but that shouldn't effect the tranny internals and the shifter, of course, goes directly into the box. The front end of those cars does flex for sure. I think it's internal too. I think I'd try to find another tranny or go back into that one. I raced a Fulvia Zagato with 1.6 drive line and had three transmissions I went through. Mine would all eventually pop out of third gear.

[simon down]

so a gearbox rebuild. I really appreciate the help from all

I'll likely be leaving it for the time being, especially as I'm going to be doing more road rallying than sprints for the foreseeing and its too much of a job for me than the problem justifies: At least it forces me to experiment with different gear shifts whilst racing!

I am looking for a 1st series spares car or running gear in order to rebuild a complete engine/subframe/gearbox set up anyway and will ensure that the gearbox gets sorted once I get this sorted. If anyone know of a car or running gear in the UK, let me know

many thanks again

Simon