What did you guys use for pistons? I just used new stock replacement OMC ones in the 207 rebuild. I now notice the shirt on the pistons of my 1985 60 hp small 100 block motor had MUCH larger cut outs in the skirt compared to the 207 and big 100 pistons. I think? this would improve performance. Do the aftermarket pistons have the larger cut outs? They would be worth trying.
I believe the piston on the right is a wisco. One on left is OMC.
http://www.boatracingfacts.com/forums/a ... 1381818957The cranks look I bit different as well, but I have not studied them yet.
My Big 100 motor has had a good life to date and shows little wear and no sleeve or crank damage. I will rebuild it next. I will use the larger cut out skirt pistons.
With my left over parts I going to build a motor OMC never build in Canada. A twin cylinder 60 hp, short shaft, tiller, electric start [only] with a nitro case and factory power trim. I think it would be a cool motor on a small 12 to 14 foot AUSSI style aluminum. I tried to buy that Aussi style aluminum boat I posted a while back, but lost out.