Likely......you never know when one will let loose but I ran about 100 hours on 32P Bravos without issue. Within about 40 hours of installing 5 blades the boat broke both XR's. (keep in mind I was running more TQ than the XR was rated for) Slip is what keeps the drive from grabbing too much water at once......but that also means you will be slower.

Will do

Less slip equals more stress, no way around it. A few years ago I installed a stelling ext box on my boat , while trying different props I tried a 5 blade Maximus and almost immediately ( the same day I was testing the prop) sheared off a billet prop shaft, I had just inspected that shaft a few days before that too, my slip numbers were around 10 % or so with the 5 and 20% or so with the 4 blade labbed. I replaced the shaft and have ran the same amount of hp/tq (1000+ ft lbs) since then without accelerated failure, 5 blades can really torque load a drive with big hp, Smitty

Mine are Hydromotives.

Are Hydro's still available?

What pitch are you running on your 38? Was going to try a Merc Maximus 24 pitch on my 42.

Mercury recommends dropping down 2" if going from Bravo I to the Maximus 5 blade...agree or disagree?

2 inches sounds right IF your using the same diameter (Maximus come 15 5/8 vs Bravos at 15 1/4)

for my application 30P Bravos were the fastest, running 86 at 5,600 rpms and 48 at 3,500. 32P Bravos were 83 at 5,300 rpms and 54 at 3,500. 28P 15 5/8 maximus were 83 at 5,250 rpms and 58 at 3,500 rpms.

Thanks for the test results. What boat, length and motor?

Formula 382 fastech. 630hp/700tq motors (dyno'ed fully dressed with ALL accessories-not dyno headers and water hose in the front)


As I said in an earlier post.....the 5 blades tore up the drives IMO.