I RAISED THE MOTOR RESULTS

[DSwatloski]

Raised it to hole four and made my test run today. I can go one more higher and think I should. Here’s why. I took a gopro camera and shot some video. I cannot see the anti-ventilation plate. I can see the little structure above the AV plate. The AV plate It is about another 2 inches under water. See the photo, I can see the little fin above the numbers 13x31, but not the AV plate. I could trim it pretty good before I got venting. However, the venting was at roughly the same trim point as when the motor was as low as it could go. When I trimmed for speed I would vent a little in a hard turn. If I just bumped the trim down in a turn, it hooked up with no more venting.

Runs were at 5000 rpm with 25.4 MPH running reciprocal courses on GPS. My finger in the photo is the reciprocal run.

I was heavy, three ice chest full of water, me about 220 and all my gear, bimini up as close as you get to having a full blown boating day.

So bottom line, I’m going back to the shop and have them raise it to the highest position and will make another run.

Also my prop is a little dinged, photos of one of the blades. I think I might want to factor that when making the prop decision.

[DSwatloski]

It went slower raising it the last hole. Going to run it again to double check. Best I could get was 24.6 MPH at 4900 RPM. I could see in the GoPro video that the lower unit was pushing water into the transom box. I had a different angle by about a foot on my pontoon rail where I put the GoPro, so I'm going to place it where the other one was and run again to be sure. If I get the same results, back down one hole and we'll stay there. Then re-prop for the RPM range, I want to see 5800 or higher to 6000.

[teecro]

I forget what was your speed before you had the motor raised up?

[DSwatloski]

Started at hole 1, as low as I can go, 22.4 MPH at 4800 RPM. Went to hole 4, one from as high as you can go, 25.4 MPH at 5000 RPM. No venting so I went up to hole 5 as high as it goes, 24.6 MPH at 4900 RPM.

Going to test again tomorrow and may drop it one and call it done. Then re-prop for RPMs and HP. Thinking a 13 pitch to start with. Spitfire??

[wwind3]

Definitely have your prop reworked. I run a 16 in pitch on my 90 Optimax--can reach redline if I overtrim. Speed 29 with aluminum prop. With 17 inch SS prop-5450 rpm and 27 mph---am changing my SS prop back to 16 in pitch. My motor is set up to where the cavitation plate is level with bottom of splashwell. Hope this helps.

[DSwatloski]

Thanks. It helps. My boat is very heavy most of the time. I'm going to prop it for the average condition and call it done.

[teecro]

Still very impressive to have gained 3 MPH with no cost involved.... I should try this myself but the wife already thinks that I'm obsessed with speed...

[DSwatloski]

Still very impressive to have gained 3 MPH with no cost involved.... I should try this myself but the wife already thinks that I'm obsessed with speed...

... and like mine, she's probably correct.

[Bryden24shp]

Still very impressive to have gained 3 MPH with no cost involved.... I should try this myself but the wife already thinks that I'm obsessed with speed...

... and like mine, she's probably correct.

And the problem is??? ... I've had the need for speed since my first boat ride. Always dinkin with them to get that last little burst... I'm messin with props and engine height on the new Manny right now. Too cold for any deep water prop swaps, so I'm beach propping.
Can't get too serious until I get 4 more hours on it, after she's officially broken in, I can really get to it. Until then, short bursts only, don't really tell me a lot. But its down to 13% slip, so its very close!

[DSwatloski]

No problem at all. I have a 14 pitch Enertia coming Monday. Going to give it a try. Motor down one hole too. I may push the Simon ECM but not until next season. How much you getting out of the new Manny?

[mzodarg]

No problem at all. I have a 14 pitch Enertia coming Monday. Going to give it a try. Motor down one hole too. I may push the Simon ECM but not until next season. How much you getting out of the new Manny?

I wish you the best with the Enertia, I tried one (15x15P) WITH HORRIBLE RESULTS. Tomorrow I'm headed to a custom prop shop and the owner tells me he has what I need. Its a customized tempest plus 14 5/8 x 17P. I'm going to test it at a near by lake (draper).


Mike

[wwind3]

Thanks. It helps. My boat is very heavy most of the time. I'm going to prop it for the average condition and call it done.

10-4. I have a fishing model with 2 fishing chairs instead of lounge chairs---front end wt is a speed killer. I still push a lot of water. Pic of me doing 29--like pushing a giant loaf of bread thru the water.


As opposed to my last bassboat 1979-Toledo Bend Tx. Stock 115 Merc-19 in pitch SS prop-slight cup in prop. engine raised 1/2 inch. Honest 55 mph rig. Venture held bassboat speed record in 80's. 82mph with rated HP. My dealer guaranteed me with a little tweaking mine would do 62 but wouldn't have a hole shot so I declined. Mine would leap out of the water and reach top speed in no time. Plus very stable at speed-almost no chine walk- a dream to drive.

[Bryden24shp]

No problem at all. I have a 14 pitch Enertia coming Monday. Going to give it a try. Motor down one hole too. I may push the Simon ECM but not until next season. How much you getting out of the new Manny?

So far 52 at 6200 RPM's, she's on the limiter. That's with a 15 1/4 X17 pitch Salt Water Series prop. I have a new 19 on it for todays run. I have to log 4 more break in hours on it before I can really push it. So I'm heading out early to put some time on it, then.... Hammer down!

[DSwatloski]

No problem at all. I have a 14 pitch Enertia coming Monday. Going to give it a try. Motor down one hole too. I may push the Simon ECM but not until next season. How much you getting out of the new Manny?

So far 52 at 6200 RPM's, she's on the limiter. That's with a 15 1/4 X17 pitch Salt Water Series prop. I have a new 19 on it for todays run. I have to log 4 more break in hours on it before I can really push it. So I'm heading out early to put some time on it, then.... Hammer down!

That is nice.

Mike, thanks for the good wishes on the Enertia. Do you still have your 15?

I just tweaked the trim on the boat today slightly lighter but got up to 27.6 and 5200 RPM sustained. I left it on the hole five, shallow as she can go. I think the Enertia 14 might work out well. The current propeller is a slightly dinged 15x15 Powertech. Ken at Propgods describes it as a "price point" prop. I think that's a nice way of saying it is pretty, but junk. The numbers today that's 11% slip on the PowerTech, which isn't too bad.

All the mechanics I've talked to have said you want the new Merc 4-Stroke 2.1 liters (75, 90, & 115) above 5500 to get the efficiency and HP. I'm hoping the 14 pitch Enertia puts me there.

BTW getting the motor height to where it is, as shallow as it can run, got me from 22.4 to 27.6. I did underskin, but that's probably 1 to 1.5 MPH at most; I measured it as best I could. So over all MPH up 5.2 MPH, 23.2%. I'll take it. If I can get to 30 MPH, I'll be satisfied. Wife doesn't want it to go any faster, she afraid I'll hurt the grandkids tubing.

[mzodarg]

DSwatloski,
I'll be trading the Enertiain in tomorrow on the custom tuned tempest. I also raised my engine one hole. The 5500 rpms is the reason I began chasing props, with the black max 15x17p I was initially hitting 4900 rpms. Raise the engine and gained 300 rpms and 3-4 mph.

I haven't underskinned yet, but that will be next once I'm comfortable with the prop.

Mike