One of my local tracks is 19 x 12m (about 62'x40') so pretty similar size. With a Novak 13.5SS, timing advanced to maximum, LRP Sphere on punch setting 8, I usually gear somewhere around 5.5-5.6.
With an 88 spur that means around a 31 pinion which I'm pretty sure won't fit in the motor mount. I tend to use 78 and 81 spurs, which means pinions in the 27-30 range which fit fine. (I think last week I used 81/29 to give 5.6.... but not 100% on that!)
Hope that helps
Oli Meggitt | London, UK
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