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Thinking of shortening the final drive ratio by switching crown and pinion gear maybe for one from the 1,0lt Polo. Does anybody know (or could they find out) the difference between the two gears??

brave.......! the answer should be out there somewhere

if it's any reference, the old 1.0 and 1.3 ratios in the mk3 were 4.2667 and 4.0625 respectively. im no great judge but i'd bet a valver 1.4 probably would share similar to the 1.3 already, if not the 1.0 even!

a small but potentially worthwhile gain that.

i think the tooth numbers were something like 64/15 and 65/16.. very nearly the smallest differences possible at that size (4.000 and 4.333 possible if you play around, and i've seen 4.125 listed somewhere - 66/16?)

then again it might be lower than 4, like 3.875

yeah, that's too small a gain. what i'm guessing is cos the valver is like all about fuel economy, they'll most likely have a much bigger difference. i'll have to look into it but i was just hoping to find a definitive answer maybe here. crown and pinion for me is a great and cheap tuning choice (if you don't use freeways much).

It'd probably be easier to change the whole gearbox for one with lower ratios - unless you're familiar with opening up gearboxes and are able to get the parts very cheaply.

actually it wouldn't be easier......and it wouldn't be cheaper either :-)


besides, the gear ratios are pretty much ok (besides 4th-5th....mayyyybe 3rd could be a little closer too but overall they're ok) so it's just a matter of the final drive ratio being a little shorter.

I don't know, I thought the valvers were more the performance end (and so closer, slightly lower geared), and the 1.4 8v would probably have wider, slightly higher gearing?

Same as the Genesis vs GT mk3s - both five gear, 1.3 litre setups, but one is single-point injection (for the sake of argument, though it's not entirely accurate, let's call that the 8v analogue) with an emphasis on economy, and the other is multipoint (16v analogue) with similar torque but much improved power and an emphasis on sportiness. To take better advantage of each engine's strengths and weaknesses and to tune them for the intended market, the Genesis has wider ("standard") gaps between the gears and an overall tendancy towards higher gearing, whereas the GT has closer gears and tends towards lower gearing (the GT shipped with either the same diff - and 1st gear - as the Genesis, or a slightly lower geared / higher ratio one with a 1-litre diff... the spec changed partway through the run).

I havent any concrete proof but i think this pattern played out in the later gearbox lines as well from some details i saw. The overall mph-per-rpm pattern was similar too, only creeping slightly higher as average engine outputs increased.

If you want a really tight, low box however, see if you can bolt on an early (?) mk3 1.0 five speed. The overall ratio spread is identical to the 4 speed (1st = 1st, 5th = 4th..... literally), with 2nd thru 4th squashed up to fit, and it also has the same final drive, the 4.267... You'll only get about 17mph/1000 in top on standard profile 13s (vs maybe 18 or 19 for the GT, and 22 for the Genesis), but it'll be Tite (1st being about 4.5mph).

(and keep away from me ashtray - it goes from 5/1000 upto 25/1000... complete antithesis of a sports gearbox )


Disclaimer - that's probably all b*llocks and i'm really just putting it in so Gareth will jump in to drop the true knowledge on you I always seem to get it wrong (never write it down, ysee, just try to hold it all in my head like that Aspergers kid that won Jr Mastermind tonight. PS watch it tomorrow - specialists subjects being Schumacher, and the (awesome) films of Hayao Miyazaki? It's going to be culture clash mayhem!)

probably all wrong cos i'm talking about a 6n2 (mk 5) you reckong the gearbox will fit?