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Hello- Here are my thoughts on what's been raised regarding the 1679cc and R&P choice: - Loss of torque in first gear: Don't worry about it. It isn't enough to make much of a difference and, IMHO, actually makes the drive easier. Remember - you have the same 1st gear ratio that a 1200cc engine had. Surely you have some room to spare :-). - Changing the first gear ratio: Don't worry about it. It's an expensive procedure. The 1st and 2nd gear ratios are determined by the mainshaft choice which, for all stock mainshafts that'll fit in a tunnel-case tranny, is essentially the same (okay, there were 3.78 and 3.80 varieties, but the end ratios are negligibly different). Aftermarket mainshafts are available, but cost >$500. - Changing the third and fourth gear ratio: Easy and cheap. If you want to, you can. - Loss of cooling due to taller cruising gear: Yes, your fan will spin slower if you cruise at a lower rpm. But, that's leaving out many other parts to consider. You also are generating much less oil temperature because you are spinning a lower rpm. And, the valvetrain and bearings will likely last a bit longer. But, your head temp will likely go up. So, it's a give and take. - 88mm machine-in cylinders make it cool better: False. They make it cool _worse_. Because of the large amount of material in them, they won't warp as easily as a 87mm or 88mm slip-in. But, also because of the large amount of material in them, they will help to impede the actual cooling. Is it enough to stay awake late at night over? No, although saying they "increase cooling" also isn't very good. And, is the gain in stability over 90.5mm cylinders enough to stay awake late at night over? For your mild application, no again. I'd just jump to 90.5mm. Me personally, I'd most _definately_ use the taller 3.875 R&P. Then, I'd play with my 3rd and 4th gear setups. If you want, you could shorten them, giving you the same cruising rpm as when you started, but ending up with a closer shift pattern. Or, you could leave them the same and help out the cruising rpm. Or, you could even make the 4th taller (use a 0.82 4th gear). Given the build of your engine (i.e. basically stock 1600 head cooling ability), however, I wouldn't go for the latter route. But as for which of the first two choices, it's up to you. Hasta, Shad Laws LN Engineering http://www.lnengineering.com ------------------------------------------------------------------- List info at http://www.vwtype3.org/list | mailto:gregm@vwtype3.org