Just plain badd-ass !

**xb03fs** · 07-16-2018, 02:32 PM

Originally Posted by Double Rigged

I agree Brad with all you are saying but with a few exceptions. One is they state 40% more torque on the low end. That is from Mercury. That being true perfect fit for the CC Market trying to get on plane with 500 people on board! It will be good to see the comparisons from Wildman but nothing beats lining up two boats up side by side at 40mph and hit the throttles! I personally do not think that motor with a 6400rpm rev limiter will out accelerate a properly propped set up 300x that will turn 7100rpm. Will it beat it on fuel, quietness, gas mileage and all around other performance sure will. But until Mercury comes out with at least a 375hp version at 560lbs V10 or Supercharged 300R I will keep my 300x's. At least as long as they run and my spare powerheads hold out! JMO

The 300 XS had a operating rpm of 5800-6100 and would overrev to 6400 before gaurdian, the 250 XS had a 5600-6000 operating range and overrevs to 6250....

The 300R has a range to 6400 and the 250 R to 6200.....

inquiring minds would love to know where the overev is allowed to go too....

**powerabout** · 07-16-2018, 06:38 PM

Originally Posted by Brad Zastrow

Two Strokes are DOA. Sorry guys Mercury is not targeting STV's with this motor. The only new boats selling are CC's, pontoons and Sport cats. Four strokes have a lot more torque than two strokes. Normally the disadvantage of the four stroke is they heavier. Not with this engine. I was told the 300R has 50% more torque than the 300XS. That will be more than noticeable in a heads up comparison.

I wonder if they meant at 1000/2000 rpm it has 50% more, ( I think they are being clever not saying were) where does your 300x/xs go to when you nail it, doesnt hold at 2000 rpm
Maybe on a big heavy boat with a buried gearcase you will notice more torque at very low revs, if thats the market then that will be ideal.
The Merc doesnt have variable valve timing does it?
A 300x produces more torque than a GM LS 4.8 but I'll bet the 4.8 is higher at a very low RPM. The peak torque rpm, almost the same but 300x about 20 higher

**Double Rigged** · 07-16-2018, 06:51 PM

Originally Posted by xb03fs

The 300 XS had a operating rpm of 5800-6100 and would overrev to 6400 before gaurdian, the 250 XS had a 5600-6000 operating range and overrevs to 6250....

The 300R has a range to 6400 and the 250 R to 6200.....

inquiring minds would love to know where the overev is allowed to go too....

Not following your over rev theory. Max rpm is max rpm. No does the 300xs make full power according to Dave Bush’s Dyno pull? No power falls off around 6200rpm however a 300x has a max rpm of 7100rpm and it makes full power to then as well as the older 280s and their max rpm. I would also assume the 300r Max’s power to 6400 rpm. There is no over rev after that.

**Double Rigged** · 07-16-2018, 06:54 PM

Originally Posted by Brad Zastrow

I am also not selling my 300X engines anytime soon. However even is they still made a 300XS I would be hard pressed to buy one if the 300R is even close in performance. Now I will be tempted to step up when they release the supercharged version of the V8 outboard.

I agree 100 percent I would take the new motor over a 300xs any day. But if you made me choose between the 300r and new 300x in the box I would take the 300x. We need to see at least 350hp at that weight to start to exceed the 300x IMO.

**xb03fs** · 07-16-2018, 10:37 PM

Originally Posted by Double Rigged

Not following your over rev theory. Max rpm is max rpm. No does the 300xs make full power according to Dave Bush’s Dyno pull? No power falls off around 6200rpm however a 300x has a max rpm of 7100rpm and it makes full power to then as well as the older 280s and their max rpm. I would also assume the 300r Max’s power to 6400 rpm. There is no over rev after that.

allisons are light. Every prop I own turns past the 6000 max operating
rpm of a 250 xs into its overrev. Even 1 of the 32p that
produced max speed turned a little past 6000. I like the punch of 28s and keep the boat off the hard limiter by backing out a touch. Every bonus rpm over recommended prior
to guardian is a blessing

**dfrank** · 07-17-2018, 02:25 PM

Thanks for sharing and yes it is Badass! I have one on order to put on a 21' Nordic and can't wait to get it. Look forward to see what you think when you run it.

**bassmasterffej** · 07-17-2018, 02:29 PM

What is your ETA on delivery? When did you order?

**dfrank** · 07-17-2018, 03:14 PM

Ordered on May 30th and the quoted ship date is July 20th. Will check with dealer next week to see if it shipped and if not when do they expect it to ship.

**gotboostedvr6** · 07-17-2018, 03:27 PM

Considering all the orders Mother Mercury had on these let us know in October how it runs.

**bassmasterffej** · 07-17-2018, 03:36 PM

I've been told 5-7 weeks on the 300R...Mercury Racing is separate from the other mercury motors so their wait times aren't as long....Yet...

ETA January 2019 for the 300 Pro XS V8 if ordered last week...

**Flightplan** · 07-17-2018, 06:39 PM

Originally Posted by Double Rigged

I agree 100 percent I would take the new motor over a 300xs any day. But if you made me choose between the 300r and new 300x in the box I would take the 300x. We need to see at least 350hp at that weight to start to exceed the 300x IMO.

7 lbs of boost should take these 300R's to ~ 440 HP

10 lbs of Boost will make ~ 505 HP

14 lbs of Boost will make ~ 585 HP

I believe we are seeing the replacement for the 400R which is nearly maxed out on boost for a 2.6 liter.

**NICE PAIR** · 07-17-2018, 06:50 PM

Originally Posted by Flightplan

7 lbs of boost should take these 300R's to ~ 440 HP

10 lbs of Boost will make ~ 505 HP

14 lbs of Boost will make ~ 585 HP

I believe we are seeing the replacement for the 400R which is nearly maxed out on boost for a 2.6 liter.

If you'd like, send me your new 300R's and I'll break them in while you're finishing your 28. ;-)

**Greg G** · 07-17-2018, 07:30 PM

Originally Posted by dfrank

Thanks for sharing and yes it is Badass! I have one on order to put on a 21' Nordic and can't wait to get it. Look forward to see what you think when you run it.

Which Nordic, the 21 Crossfire or the 20 SR? Very cool.

**Chaz** · 07-17-2018, 07:48 PM

Originally Posted by Flightplan

7 lbs of boost should take these 300R's to ~ 440 HP

10 lbs of Boost will make ~ 505 HP

14 lbs of Boost will make ~ 585 HP

I believe we are seeing the replacement for the 400R which is nearly maxed out on boost for a 2.6 liter.

Now Flight we both know that there ain't enough room to fit a I-phone 8 between the block and cowl on one of them new fangled car motors standin on end . Let alone put a "leaf mulcher" on it somewhere ….

Now on the other hand …. The two stroke boys aint layin down ..

2.14 oz/sec 160 HP

3.6 oz/sec 250 HP

5.02 oz/sec 370 hp

Course that's on top of a couple uh beat-up 225's

**JPEROG** · 07-17-2018, 11:16 PM

Originally Posted by Double Rigged

I agree 100 percent I would take the new motor over a 300xs any day. But if you made me choose between the 300r and new 300x in the box I would take the 300x. We need to see at least 350hp at that weight to start to exceed the 300x IMO.

Ron,

You know what a fan I am of the X motors-"I have several in my collection of junk"--I am waiting to rig two of my boats with these and I have done all of the homework...I promise-

Joe