Triple engine fountain guys
 

Has anyone or does anyone run a one size pitch larger prop on the center drive? Reason I ask is that my center motor spins about 200-300 rpms more than the outers. My center prop doesn't have a diffuser ring on it but I doubt that is giving me that much more rpm. I have heard that this little trick can gain you a little bit and I'd like some opinions before I go chasing down a 25 or 26 four blade. I run 24 Bravos on it now, one RH and two LH. All three drives run -2 IMCO shorties.

That seems to run counter to the issues I've had with my triples. My center tends to run lower by 100-200 RPM because the drive is deeper than the outers (ie: I have to give the center a little more throttle to make the RPM's even). I think you might have something there with the diffuser. Have you tried to swap one of the outer props with the center to see if it is the diffuser?

No but I will. Trying to think back to last year when I ran my 5 blades and whether or not the rpm's were even across the board.