Top speed 252 with 502

[thunder550]

This weekend the weather was a little cooler, found some nice smooth water and let her rip. I was able to trim it all the way up and saw 60 on the speedo and maybe 4900 RPM, got really excited and had my wife open up GPS to verify...56 on GPS . Better than the previous weekend though.

Fozzy, do you feel like you gave up anything on the hole shot with the Enertia? I tried to pay attention to how the boat tracked in corners this past weekend and I'm not real impressed. If the Enertia will grip better in the corners both cruising and pulling a tube I may go ahead and jump on over to it. I guess with the 502 I shouldn't worry about losing much about the hole shot, eh?

I just ran some info through the prop selector on Mercury's site and these are the recommendations based on my inputs. The engine year doesn't go older than 2000, hopefully that won't make much of a difference.

prop suggestions.jpg

[Driller]

I thought I read somewhere in the Volvo Penta literature that only a stainless steel prop should be used over a certain horsepower. I thought it was 350? Are the Mercs different?

[thunder550]

Are you referring to the X7 Alloy from the screenshot above? I googled it and found this:

"A revolutionary new alloy from Mercury that shatters the rules of propeller design.
--30-percent stronger than conventional stainless steel
--Four times more durable than conventional stainless steel
--Allows prop designs that are impossible with conventional stainless steel
--Patent pending
--Currently on select models"

...and this:

X7 Alloy: Designed to do the impossible.
Making Rules. By rewriting the rules. Thirty-percent stronger and four times more durable than conventional stainless steel, Mercury's revolutionary X7® alloy makes the impossible possible. Prop designs that couldn't be done. Performance levels that couldn't be reached. Now within your grasp.

[Driller]

Holy Cow!!! It must be made of Cost-a-lot-alloy or Unobtainium.

[thunder550]

I'm seeing about $600 a pop for a new 8M0040404...

[Driller]

Plus the solid hub assembly?

Mercury Mercruiser: Mercury Mercruiser Alpha & Bravo One
Alpha and Bravo One Sterndrives - All Horsepowers
15 Tooth Spline
For 400HP+ Use Flo-Torq solid hub assembly. Replace A46 with A55 or order hub kit part number #835258K2
For Bravo One XR and XZ drives, Use Flo-Tor 1 1/4" hub assembly. Replace A46 with A65 or order hub kit part number #840389K06

[cmattj]

I'm seeing about $600 a pop for a new 8M0040404...

Just a thought.. this style of boat has a low " x dimension " which is the outdrive and prop is deep so trimming up won't air it or cause cavation.

The 16 " diameter prop is too big for your set up .

look to try a 23 p mirage standard .( the non plus is designed more for bow lift and not stern lift.. at 14 3/4 it will be faster..

The mirage plus adds cupping to prevent slipping but causes stern lift as result.. that will give you grip at cruise speeds and take off but hurt your top end.

Labbing or thinning props helps free them up so using a higher pitch can be achieved without lugging..

Find a used mirage 23 standard and she will be fastest at WOT..

Geeze I wish I didn't have 6 blades spinning on ours but I do love the cruise speed slip is about 8 percent.

[thunder550]

Plus the solid hub assembly?

Yeah that would be extra

Find a used mirage 23 standard and she will be fastest at WOT..

That's what is currently on it...unless I'm misunderstanding what you are recommending?

[cmattj]

Plus the solid hub assembly?

Yeah that would be extra

Find a used mirage 23 standard and she will be fastest at WOT..

That's what is currently on it...unless I'm misunderstanding what you are recommending?

Just referred to your prop selection you posted. You may have the best if it doesn't have the plus..

Once you run her in good conditions.. sea level barometer of 30.0 or more you'll be hitting nyour goal

[thunder550]

Plus the solid hub assembly?

Yeah that would be extra

Find a used mirage 23 standard and she will be fastest at WOT..

That's what is currently on it...unless I'm misunderstanding what you are recommending?

Just referred to your prop selection you posted. You may have the best if it doesn't have the plus..

Once you run her in good conditions.. sea level barometer of 30.0 or more you'll be hitting nyour goal

10-4 thanks!

[Fozzy STI]

I am also talking about the mirage not the plus.
Top end speed almost the same as the enertia,but the enertia a little bit quicker out the hole, midrange much more respond, grip in the corners fenomenal .. but that is on my boat....
I always say try before you buy
Here in holland we always can try them, if you damage it you have to buy it.

[thunder550]

I called Ken at PropGods (site sponsor over on THT), he has a demo program for $30 plus shipping. Trying a Mirage Plus (QS Thunderbolt actually, but apparently the exact same thing) in the same pitch to start with, to rule out wear or repair or something causing high slip numbers on my current prop. Depending on how that goes I may try a 4 blade Powertech SFS4, that would be better for watersports but I don't really want to lose any top end. Like cmattj, Ken also said stern drives normally don't like the bigger props like the Enertia Eco, but it might be worth a shot I guess.

[cmattj]

That's a nice program he is offering!

Makes sense to try one with a fresh face and tips.. could help a bunch .

[thunder550]

Yeah it's pretty awesome! After paying shipping 2 ways it's probably going to be $70-$80 total, but better than being stuck with a $500 prop I'm not happy with. I like BBP's method of scouring CL for deals but I don't have the patience to wait for the right one to pop up

It's probably going to be the weekend of Nov 18 before I can get out and try the Thunderbolt, but I'll keep this thread updated with results.

[AsLan7]

.

I called Ken at PropGods (site sponsor over on THT), he has a demo program for $30 plus shipping.

.
I thought the cool thing about PropGods was his ability to meet you at the boat ramp and allow you to test any prop you want that he has in his inventory (although at $95 per hour).

This must be just a Florida thing--trying props out of their " mobile truck inventory".