Set-up a 13r

[JETMORE]

Am restoring my 13r and have heard various opinions on the 75 looper nitro lower unit. I have a non-nitro motor. I would love some more opinions on whether or not a nitro lower will really help my topend much. The consensus i get is that a stock lower with a hydromotive nose cone will get me within 2 mph of a nitro gear case. I am not actually racing this boat, so if it is only 2 mph difference, i can't justify spending a lot of money on a nitro, for 2 mph, but some guys say it is 5 mph difference. By the way, supposedly this boat was an noa champ in the early 1970's. It is very light and two people can carry it.

What are your thoughts?

Thanks so much.

Ronny
410 394 9000

 

[Lotus 50]

The standard gear case is 2.42 (29:12)
Nitro case is 1.87 (28:15)
23 is the most pitch you'll easily find. OMC made 23 cleavers and the 23 SRX.
6000 rpm would give you maybe 50 mph with the standard case, over 60 with the Nitro.

I think the biggest problem with the standard case would be props.