For rpm in top gear see this thread:
http://www.lotuseuropa.org/LotusForum/index.php?topic=1422.msg12697#msg12697Specifically:
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For the sake of comparison, if you were cruising along at 4000 rpm in 4th with a 336 or 352, then the equivalent road-speed with the various 5-speeds would require these rpms:
Rpm .... overall ratio
4000 @ 3.663:1 = 336 & 352 in 4th
3771 @ 3.454:1 = 395-00 in 5th (it's a close ratio 5-speed, not a over-drive 'cruiser')
3591 @ 3.289:1 = 365-07 (stock Europa Twin Cam Special)
3552 @ 3.253:1 = 395-11, -04 thru -09, -12, -21, and NG3-025
3233 @ 2.961:1 = NG3-064 (but it has a very low 1st gear and poor intermediate spacing).
Note that in 5th, there's negligible difference between the Europa's 365 5-speed, and the 395-11 or -21.
Regards,
Tim Engel
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The problem with almost all of the NG series of transaxles is that they have a very low first gear. Remember that the 336/352 have a 3.56 diff while the rest have a 3.78. The NG series combine a lower first with a lower final drive. 1st ends up topping out well under 50 kph! In addition, 5th gear drops 500 rpm at the most off that of a 336/352. The one 5th gear that really does the trick, the 0.78, is not easily found and is still paired with a too low first.
I'm not saying that changing to a 5 speed is a bad idea, just that, as with any modification, there are pluses and minuses.
