I have a question about props on a Fountain vs. Cigarette hull. I recently purchased a pair of Cobra 1000's from a guy who had them in a 38 Cig TG with out steps. He was running Speedemaster 3's and 17 x 29 3 blade cleavers. He was running 94 mph at 5800. I bought the motors and trannys and the 17 x 29 props. Maybe I'm way wrong but I figured pretty close to the same performace in my non stepped 40 Fountain with Speedmaster 3's. Well at testing this morning in Havasu with the 17 x 29 props we had a hell of a time getting on plane and were at 54 mph at 6000 with tons off throttle left, we hit the rev limiters with no problem. What's up with this?? Any explanation for this?? Then we went back to our old props 17 1/2 x 31 3 blade cleavers and the boat jumps up on place in seconds but we still have plenty of throttle left at 75 and 5800. Any ideas? Just seems very wierd to me. Do I need even more prop? And why is the Fountain setup so different from the Cig?

Well I can see this will be another cig vs fountain thread but if I had to guess your fountain is probably lighter with a different x dimension. Also are you sure the gear ratios are the same on your drives as the guy with the cig

Thanks shepnic74. All good points that I didn't think of. I am going to call the guy I bought the motors from and see what ratio his drives were. That could deffinatly explain it.

It's more likely to be an x dimension difference than gear ratio. You posted a pic of your drives once before and iirc they are pretty high. Your at 34% prop slip right now. I'm thinking your going to need a 4 blade prop at minimum. The cig was most likely rigged with the propshafts 5" below the bottom.

Interesting! How do you calculate the prop slip? Also finding props for the old SSM 3's is not an easy task. From what I've bee told nobody makes them anymore. Do you know if this is true? Did 4 blades ever exist for SSM 3's?

Brett has a prop slip caculator on his site. Bblades
http://bblades.com/propeller-slip-calculator/

I have 4 blade 19 spline props on my 3's on my hawk. I only have about 600 hp, turning 17.25x25p 4 blades at cruise my slip is only 10%. Prop shafts 3" below the bottom. You can use 26 spline props from 3a's, 5's or 6's using the adapters from arneson.