splashandburn
New member
What are you guys running for drive height on your BT's? Anyone know the approximate depth they are below the running surface directly in front of the drives? Any help would be greatly appreciated.
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Ratickle
Founding Member / Super Moderator
splashandburn
New member
Yes. I never got the boat dialed in last year - ended up blowing a motor @ less than 30 hours. Both motors reworked (again) and pushing even more lower now. I'm getting extremely high slip numbers running a 32P Bravo I prop. Just received new drive couplings to put the drives back to stock depth which looks to be close to 4" below the running surface.
splashandburn
New member
Yup that's it with the spacers installed. Removed now and IMCO SCX uppers installed.
splashandburn
New member
I haven't. I do think the boat needs bow lift though I can almost feel it plowing at speed. I'm wondering if the spacers were pushing the bow down?
endeavor1
New member
My 02 46 with KE675s or as dyno proven 699s ran BMAX drives with standard XR lowers with Hydro P5X props. Boat handled good, carried the nose and was enjoyable with minimal tab. Same boat with 4 blades became an absolute turkey. Try no spacers and P5X props.
Btw, my first 43 had -2 lowers and when I put standards on it it slowed and completely changed for the worse its handling. John P with No-Comp (trip 850) 46 saw gains after we discussed -2 vs std lowers.
Short drives/more prop... Have fun
Btw, my first 43 had -2 lowers and when I put standards on it it slowed and completely changed for the worse its handling. John P with No-Comp (trip 850) 46 saw gains after we discussed -2 vs std lowers.
Short drives/more prop... Have fun
splashandburn
New member
Hmmm....not sure what I've got going on then. I was thinking that having the drives that deep was increasing my slip numbers. I'm running close to 30% slip @ WOT.
splashandburn
New member
New motors dynoed at 890 hp. Boat seems to hit a wall @ 74 mph. How is it getting on plane with -2? I seems to really blow out the 32P props WITH the spacers installed - can't imagine what it'd be like with 4" less in the water
endeavor1
New member
4 blades on my 46 blew out, my current 43 did too until b blades worked them. 5 blades on my 46 hooked up and rolled on plane no issues.
If I had 890hp and hit 74 I'd be crying. I hit that Friday night late under the community bridge @ Loto with my catastrophe of power I call engines...fWIW, when my engines were procharged they were odd to understand the power and along with finicky. 775hp per dyno.
Call me if I can be of any help to discuss my setups.
If I had 890hp and hit 74 I'd be crying. I hit that Friday night late under the community bridge @ Loto with my catastrophe of power I call engines...fWIW, when my engines were procharged they were odd to understand the power and along with finicky. 775hp per dyno.
Call me if I can be of any help to discuss my setups.
Ratickle
Founding Member / Super Moderator
Also, with your spacers installed, I have to believe the cavitation plate was running in the water even at WOT. They were just too low.
Typically the water starts to rise to its normal level as soon as it leaves the transom. Your cavitation plates appear to be lower than the bottom of the boat in the photo. I think they were displacing water and aerating the water to the prop also.
Typically the water starts to rise to its normal level as soon as it leaves the transom. Your cavitation plates appear to be lower than the bottom of the boat in the photo. I think they were displacing water and aerating the water to the prop also.
splashandburn
New member
I have a set of stock Bravo I 28P props that I know are untouched and a set of Bravo I 32's that were Mercy labbed.
splashandburn
New member
Yes both are close to 1/2" down and at the same level. Must just be the pictures angle. .
splashandburn
New member
The 32's seem to be the right size as I spun them to 5100 rpm but it seemed to be dragging. I could actually feel (and see) the speed increase if I turned the boat slightly. The water was dead flat though.
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