Getting my 1st 300R V8 this week.

**XstreamVking** · 07-10-2018, 05:39 AM

Carbon fiber parts /ceramic block would cut weight in half. Costs would double though......

**22R** · 07-10-2018, 05:52 AM

Originally Posted by engineermike

The fact that they added 1.4 liters of displacement through 2 cylinders, 2 con rods, and a longer crank, plus a counterbalance shaft, 4 camshafts, 32 valves, elaborate cylinder head castings, and a pressurized oil system, and added a scant 7 lb over the outgoing 2-stroke is an engineering marvel. But you think the new 4.6 4-stroke v8 should have been 23 lb lighter than the 3.2 2-stroke v6 it replaced if they had just put a little more thought into it?

And just think with all those parts churning 5500 RPM how cheap it will be to fix if it breaks.....Merc knows

22R

**powerabout** · 07-10-2018, 05:59 AM

scary when you have ultra thin castings and seawater cooled in the same sentence

**engineermike** · 07-10-2018, 06:13 AM

First it's too heavy, then it's too light. First it won't make the power, then it makes too much torque. The only thing you guys have proven is that you won't be satisfied unless merc puts the 2.5 back into production. I have bad news for you....

**afr** · 07-10-2018, 06:17 AM

is this those bran new ones i see with the new hood / 4 strokes

**powerabout** · 07-10-2018, 06:40 AM

Originally Posted by engineermike

First it's too heavy, then it's too light. First it won't make the power, then it makes too much torque. The only thing you guys have proven is that you won't be satisfied unless merc puts the 2.5 back into production. I have bad news for you....

You make it sound like its going to be the last outboard ever made....

**powerabout** · 07-10-2018, 06:48 AM

Originally Posted by XstreamVking

Carbon fiber parts /ceramic block would cut weight in half. Costs would double though......

plastic, magnesium, lots left on the table for next years version

**engineermike** · 07-10-2018, 08:23 AM

Originally Posted by 22R

And just think with all those parts churning 5500 RPM how cheap it will be to fix if it breaks.....Merc knows

22R

Have valvetrain failures been a big problem in 4-stroke outboards?

**22R** · 07-10-2018, 08:35 AM

Originally Posted by engineermike

Have valvetrain failures been a big problem in 4-stroke outboards?

Don't know don't own one. Outboards generally do not rack up time like car engines. Time will tell. They may be uber reliable but I am just saying if they are not think about the cost of all those parts.....They are high tech cool motors for sure though.

22R

**powerabout** · 07-10-2018, 08:38 AM

Originally Posted by 22R

Don't know don't own one. Outboards generally do not rack up time like car engines. Time will tell. They may be uber reliable but I am just saying if they are not think about the cost of all those parts.....They are high tech cool motors for sure though.

22R

its not use its left unused and parts go rusty

**22R** · 07-10-2018, 08:59 AM

Originally Posted by powerabout

its not use its left unused and parts go rusty

That is a good point to... I just think of putting my GMC in L1 and driving with the revs up and it not shifting. Turning 1500 to 3K is one thing but long term 5500-6000 is another but I guess Merc has plenty hours of testing on them.