F-2 Speedy

iTrader: (6)

Previous owner of my boat tried B max's and the boat slowed and handled different, put the XR's back on.

veloc410

From all articles I've read going back to the 1990's . Whatever drive you were running the 1.5 ratio was always faster than the 1.36 . Maybe that's why they ran slower. BMAX was always 1.3 correct. Someone mentioned higher speeds earlier in thread with 1.65 ratio

veloc410

Well Any way interested in what glassdave was up against. Just don't know if case will hold up. Hell you could have strong gears but if the case doesn' hold form the gears will blow up anyway. Damm??

glassdave

iTrader: (1)

I was mostly asking out of curiosity, at a race one time Jim Simmons told me the helical XZ drives were slightly faster in SV but also slightly weaker. personally i wont build anything more then about 550HP on any Bravo derivitive, just not my thing.

as long as we brought up gear ratios what about 1:36 gears over 1:50? i have a friend thats hitting a wall with his current set up where he is seeing high slip numbers at the top end of 30P B1's and he is considering dropping to 1:36 gears and switching to a 28p B1 to pick up a better slip number, this is based on the thought that the 28 is a better prop with inherintly less slip.

endeavour32

iTrader: (4)

I did back to back testing two years ago, with 650 hp x2 in a Formula 292. I gained right around 1 mph with X gears, maybe 1.5 if I was lucky. The XR gears will handle more power but they don't last long. You will see lots of post on hear from Mr Gadgets on the subject. His rule of thumb was, if your not breaking the teeth off x gears, that's what you should run. I sold a drive to a guy this summer with X gears in an IMCO case, and he pushed 900 hp though it for a weekend poker run. I told him I doubted it would survive, but it did, and I can guarantee it wasn't babied. What boat are you thinking about for this? Weight does come into play.

F-2 Speedy

iTrader: (6)

What kind of power is he making, what rpm is he spinning the 30's

glassdave

iTrader: (1)

actualy i am just thinking a few projects ahead. my next boat will be a 43 with speedmasters. i would like to build a thirty something-ish six pack boat someday with no cabin. Like a 33 Powerplay or ???

glassdave

iTrader: (1)

cant recall the exact numbers but its a 30 SleekCraft running just under 90 with about six hundred plus HP a side spinning at a little over 6000 rpm. I think his slip was in the high 20 something percent.

RBeyer

I ran a B-Max 1.3 behind 720 HP and 727 TQ. It ran for 6 years without any issues. I did change the gear lube every 25 hours. As far as I know it is still running strong today.

veloc410

They just bolt up to bravo humble correct? Any mods to get them working