Joined: Aug 2017 Posts: 3,329 Threads: 372
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You might be interested to read the comments on the Nippy gearbox for sale [post] on the forum; the Ruby is a fair bit heavier so if you haven't got engine mods, you might find you need the gearing you have at times if hilly...
Joined: Aug 2017 Posts: 3,394 Threads: 106
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Location: Darkest Bedfordshire
It would be something like 12% higher geared in 1st, 2nd and 3rd compared with a standard 4-speed synchro box.
Whether that would be beneficial rather depends on how you plan to use the car, but most A7 drivers concur that standard 1st gear is a bit too low to be useful and the gap from 3rd to top is too great, so it probably wouldn't do any harm. As CR boxes go the Nippy ratios are not extreme.
The price of a new CR gear set is around £200 so as it stands that box is a bargain, assuming it's in good order.
Joined: Aug 2017 Posts: 532 Threads: 46
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Location: Oakley, Hants, UK
Car type: 1929 AD Tourer, 1930 Rosengart LR2, Rosengart LR4 Van 1938 APE Tourer (Opal)
I fitted Nippy ratios to my standard four speed box that is installed in my APE (Opal) and in my opinion it has made a world of difference. I particularly like the third gear.
I am always interested in any information about Rosengart details or current owners.
Joined: Aug 2017 Posts: 2,748 Threads: 31
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Location: Auckland, NZ
The standard step 1.66;1 between 4 and 3 is more akin that 3 to 2 of medium and large 3 speed cars. Some 1950s smaller 4 speed were 1.5:1 but most 1.4 or so. It is useful to divide what you consider prudent top speed in 4th by the ratio step to find equivalent in 3rd. Stock 50 mph gives 30 mph. In the day few would exceed 45 mph corres just 27 mph. Neverthelss not as tedious as the many small 3 speed cars near 2:1 down to 2nd. As above the low 1st gear enables starts on steep gardients loaded even with stock engine (clutch permitting).
Bit of a gamnble but unusual for input or layshaft 3rd gear to fail and most else replaceable.
Joined: Sep 2017 Posts: 100 Threads: 32
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Location: Hampshire
I agree with Derek, I have fitted a Nippy ratio four speed box to my 1938 Pearl and think it makes it a much more driveable car.
I previously tried a box with true close ratios (Super Accessories). This was not good for a relatively heavy car despite the engine being mildly tuned.
