Getting my 1st 300R V8 this week.

**mach351** · 07-18-2018, 08:40 PM

Aren’t some of the Hydromotives 15+?

**Greg G** · 07-18-2018, 08:42 PM

I may have lost this back earlier in the thread but what is the lower unit diameter of the 300XS Sportmaster versus the 300R's Sporty? Also, is the skeg itself longer/deeper?

**Z06man** · 07-18-2018, 08:46 PM

300r

**Z06man** · 07-18-2018, 08:48 PM

Wildman

**engineermike** · 07-18-2018, 08:50 PM

Originally Posted by Greg G

I may have lost this back earlier in the thread but what is the lower unit diameter of the 300XS Sportmaster versus the 300R's Sporty? Also, is the skeg itself longer/deeper?

4.8" vs 5.44"

**Z06man** · 07-18-2018, 08:52 PM

Warming up

**NICE PAIR** · 07-18-2018, 09:13 PM

"Cool"

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**LongShot** · 07-18-2018, 10:09 PM

Uncharted waters for sure but nothing that can't be designed around. Huge step change in our wheelhouse.

**JPEROG** · 07-18-2018, 11:32 PM

To give you guys an idea of how much torque this thing makes- I took a 33 Hering 4 blade thru hub with me that my STV would not pull above 2000 rpm just last week. (I had a friend over and he and his son wanted to go for a ride so I figured that trying this thru hub would carry the weight better with my friend "260Lbs" being in the back seat. My thought is that it would act as a gear case extension and hold the transom up for a 40 mile river cruise). I didn't say anything to Randy about the vent holes being so small and the experience that I just had with it. We bolted it on and the boat was up on plane within a boat length. We also had 20 gallons of fuel, Paul, Randy and myself in the boat with the 34 x 15-1/4 heavy ass 5 blade and the boat jumped right up with the motor mounted 2 1/2 above the pad. The other big difference is that if you are cruising at 3K range, crank the boat into a fairly sharp turn and maintain your throttle position, it won't even drop the tach a hundred rpm.

We get a tune and gear set in these things and there will be nothing more needed in my opinion.

Anxious to run it with Randy's new CNC that should be here by the weekend.

Joe

**madmatic** · 07-19-2018, 12:43 AM

Thank you Randy and to all those involved in giving us accurate updates and opinions.

**dcarter** · 07-19-2018, 05:46 AM

Randy,
When setting up my friends boat after going from a 2 stroke to a 4 stroke we found that the 4 strokes do not like the ported props like we run on the 2 strokes. The torque of the 4 stroke seems to like a solid hub.
I did not see you mention this in your test but may be something to consider.

dc

**Hot Shot Merc** · 07-19-2018, 07:03 AM

Randy,Joe ZO6 Great job testing and tuning

.

I know your just getting the dial in started but what are yall's thoughts on adding a hull water pick up and raising that big case out of the water more? Can ya get enough diameter to make it work? Do ya think there could be any gains?

**V-bottom** · 07-19-2018, 07:59 AM

Originally Posted by JPEROG

To give you guys an idea of how much torque this thing makes- I took a 33 Hering 4 blade thru hub with me that my STV would not pull above 2000 rpm just last week. (I had a friend over and he and his son wanted to go for a ride so I figured that trying this thru hub would carry the weight better with my friend "260Lbs" being in the back seat. My thought is that it would act as a gear case extension and hold the transom up for a 40 river cruise). I didn't say anything to Randy about the vent holes being so small and the experience that I just had with it. We bolted it on and the boat was up on plane within a boat length. We also had 20 gallons of fuel, Paul, Randy and myself in the boat with the 34 x 15-1/4 heavy ass 5 blade and the boat jumped right up with the motor mounted 2 1/2 above the pad. The other big difference is that if you are cruising at 3K range, crank the boat into a fairly sharp turn and maintain your throttle position, it won't even drop the tach a hundred rpm.

We get a tune and gear set in these things and there will be nothing more needed in my opinion.

Anxious to run it with Randy's new CNC that should be here by the weekend.

Joe

Great Info!!

Hopefully the results that you have experienced will be enough to convince Mercury to offer a 15" or 16" mid section option for the performance market. With the higher engine height vs the 300xs along with the higher "x" transom mounting height the engine will look top heavy on most performance boats and bass boats. I understand the oil pan must be close to the water level - but hopefully they can engineer something to work.

That looks like a much beefier front mount seastar cylinder. Is that included with the engine or still an aftermarket option?

**JPEROG** · 07-19-2018, 08:10 AM

Originally Posted by Hot Shot Merc

Randy,Joe ZO6 Great job testing and tuning

.

I know your just getting the dial in started but what are yall's thoughts on adding a hull water pick up and raising that big case out of the water more? Can ya get enough diameter to make it work? Do ya think there could be any gains?

Rob,

I have never seen it not work before but I think having five or six blade tips to work from is going to be the answer for these motors. Paul went back with the camera and we had the case fully surfaced with all of us in the boat running around 60 "water pressure was between 5 and 10" but always stayed cool. They have what it takes power and torque wise, now we just need to make blade efficiency and set up translate into mph. Grant has told me several times now that I need to get rid of any propellers that don't have at least five blades on them but I am hesitant with the small single engine boats because I have experienced the "paddle wheel" effect and it not very good for the blood pressure.

Everyone needs to also realize that this was the worst possible conditions that we ran this thing in (94 degrees, 100% humidity, and the motor is brand new) so things will only get better from here.

Joe

**JPEROG** · 07-19-2018, 08:16 AM

Originally Posted by V-bottom

Great Info!!

Hopefully the results that you have experienced will be enough to convince Mercury to offer a 15" or 16" mid section option for the performance market. With the higher engine height vs the 300xs along with the higher "x" transom mounting height the engine will look top heavy on most performance boats and bass boats. I understand the oil pan must be close to the water level - but hopefully they can engineer something to work.

That looks like a much beefier front mount seastar cylinder. Is that included with the engine or still an aftermarket option?

I think that there will be an aftermarket "explosion" for these with opportunities only limited by your budget. I have been down this path with lingenfelter when I took my corvette to them-"speed cost money-how fast do you want to go" and that's no b.s. with them. If I wanted a 1200 h.p. street rocket, they can make it happen but you are going to pay. When someone like them get involved in this thing, it will be endless.

Joe