5 blades for a Black Thunder
#1
I'm using 26 pitch 4 blade Bravo 1's now on my 43 Black Thunder with twin 650+hp through 1.5 Bravo 1 drives with extension boxes and -2 Imco shorties. The boat hooks up well at top speed going 76-78 at 5200 rpm but the mid range is poor, too much slip. Prop is about 4 inches below the boat and I don't think the drive coolers help either. I was thinking about going to 25 pitch Hydro P5x's. Are they small enough? I don't want to slow the engines down any more and preferably I'd like to gain a couple of hundred rpm. How would these work on my boat?
#2
Ian,5 blades help to kill bravos's,keep that in mind. My slip has always been around 18-25% on my boat running a ton of torque (900 plus ft lbs) with bravo 4 blades. Last year I tried a 5 blade maximus and sheared off a billet prop shaft in only 10 passes,the slip was around 8 %,yeah,the cruise speed would have been phenomenal but I now know that that extra slip is what helps keep my drive from breaking,Smitty





