Gavin mentioned the 369 gearbox, too.
That's right. I found that the 369 gearbox from Renault 20 or Renault 30 was available with the 4.125 (33:8 ) final drive ratio. If I could find one of those, that would be great. But as the Renault 20 and 30 were not very succesful models, the gearboxes seem to be very rare. I have also found out that there is a 385 gearbox with an even shorter final drive (4.25, 34:8 ), but that was used in the R16, thus 5 reverse gears in this case. Of course, the 37:9 ratio (4.11) as mentioned by Gavin would also be great.
The 5th gear from the 365 gearbox (29:31; 0,935), would be nice to have, but is not so absolutely necessary. The step from 4th to 5th would not be great. 3rd and 4th are a little bit too long to fit perfectly to this 5th gear. Thus, a 33:8 or 37:9 diff would be the best for me, when having also cost-effectiveness in mind. If I find one and it fits into my 395 gearbox, I'll make a party. Together with the Quaife ATB, that would gain me a lot of lap time on slower circuits like Zolder.
Thus, the most important thing for me is now, to get to know, if the shaft of the 369 bevel gear has the same spline as the 395. Is there anyone here, who can confirm or deny that?@jbcollier: You use the Quaife diff for the 336 gearbox in your 395? I found on the internet also a Quaife diff for 5 speed Europas. But it has another dimension (crown wheel spigot dia 110 instead of 104 mm). Thus, will this only fit the newer gearbox generations like NG3? Please refer to attached sketches.
