Logo

Yam 90 on tunnel 18ft only gets 3800 rpm wot

realbricky

New member
I've got an 18ft G3 Tunnel

I've got an 18ft G3 Tunnel with a 90 2 stroke Yamaha. Dealership installed 4 blade SS prop with a (17 pitch I think). I only got 30 mph at 3800 rpm max. I borrowed a friends prop off his 60 hp yamaha and now I get 34 mph at 5200 rpm. Is this where I should be or can I get more speed. My friend says he can go 34 with his 60 on an 18ft ( not a tunnel).
 
Your boat should go alot quick

Your boat should go alot quicker it sounds like the outboard is mounted too low check where the cav plate is at full speed and post back
 
"Thank you I will try raising

"Thank you I will try raising a little. G3 also got back with me and recommended a prop that appears much smaller and with less pitch. I will definitely use your suggestion, been wanting a hijacker anyway."
 
Back
Top