• RECEIVE THE GIFTS MEMBERS SHARE WITH YOU HERE...THEN...CREATE SOMETHING TO ENCHANT OTHERS THAT YOU WANT TO SHARE

    You know what we all love...

    When you enchant people, you fill them with delight and yourself in return. Have Fun!!!

  • 0
Sign in to follow this  
gunflint

More Horses

Question

gunflint

I haven't seen any posts on improving horse power in a stock outboard. Is it cost prohibitive? You always see people modifying cars,sleds, ATV's,etc, why not outboards. Other than prop changes is there a way to change gears or modify carbs, put in oversize pistons, etc. It might be kind of fun to blow by other 25s with a 25 modified to 40hp.

Share this post


Link to post
Share on other sites

14 answers to this question

Recommended Posts

  • 0
JohnMickish

Nitrous Oxide!

Share this post


Link to post
Share on other sites
  • 0
upnorth

I was reading on about that on a boating forum and the general concensus was it would be cheaper to just plain buy a bigger outboard.

Share this post


Link to post
Share on other sites
  • 0
JohnMickish

Seriously, I don't know how a guy could do it economically and really gain anything. If you are running a 4 stroke motor you could maybe get a custom ground cam but even if you gain 5%, what are you gaining? If you have a 2 stroke you could send the block away and have it ported but then again, what would you really be gaining, and you would for sure lose your idle quality.

Share this post


Link to post
Share on other sites
  • 0
delcecchi

There have been many articles in Bass and Walleye boats magazine (they have a web site also) about just this. Check it out.

Also be aware that modifying outboards newer than maybe 1998 or so is against the law.

Share this post


Link to post
Share on other sites
  • 0
Valv

Quote:

Nitrous Oxide!


Turbo !!!!

Seriously, where's the TurboDiesel Outboard ? Can you imagine the take off and torque grin.gif

More seriously as they already replied the costs to increse power and reliability issues are so large it is not convenient. If you think about the difference in speed from a 15hp to a 25 hp will be probably 4mph... and same for most other outboard size, you realize any extra expense is not worth it.

They have race motors, yes but cost of them is prohibitive and they are very unreliable.

If you had an inboard though you could have more "room to play" but watch your outdrive....

Share this post


Link to post
Share on other sites
  • 0
JohnMickish

Valv, a turbo would be the thing to do but to take an existing outboard and re-engineer the exhause manifold system to make it external to mount a turbo then route it back into the lower unit would be a major undertaking. There has to be a reason why we have turbo snowmobiles and PWC's but not outboards. Maybe thats why Mercury went with a blower instead of a turbo on the Verado. That and the holeshot would pretty much suck with a turbo in a boat. Not that easy to load it against the converter! grin.gif

A turbo diesel would be pretty sweet but the weight/size would be a major factor for an outboard.

Share this post


Link to post
Share on other sites
  • 0
Valv

Darn, I though I was goint to see the sticker "Lund powered by Cummins"

Also I was gogin to get a sticker like I have on my truck that says "Real trucks (boats) don't have spark plugs" grin.gifgrin.gif

I am just giving you hard time John, I am bored this afternoon.

Share this post


Link to post
Share on other sites
  • 0
gunflint

Valv,

I wouldn't expect to see a pull start on your turbo. grin.gif

I didn't know it was illegal to modify a newer outboard. You learn something every day here. That dang sierra club has every angle covered. smirk.gif

Share this post


Link to post
Share on other sites
  • 0
Valv

Quote:

Valv,

I wouldn't expect to see a pull start on your turbo.
grin.gif


Gunflint, as a famous comedian says "..that's funny right there..."

I would like to see somebody face expression with a Powerstroke reading manual where it explain how to pull start the motor in case of failure.... grin.gif priceless !!!!

Now that I think of it, when I was young (very young, which means a long time ago) I had a French car that had a cranking handle with spare tire carrier, if your battery would fail and you needed to start it you could have used the hand crank....brand was Citroen and they were actually pretty good cars.

Share this post


Link to post
Share on other sites
  • 0
kslipsinker

I have a Merc 40 and my buddy runs a Merc 30, both four strokes. They are identical, with the only difference being a different computer modual.

Share this post


Link to post
Share on other sites
  • 0
Valv

Quote:

I have a Merc 40 and my buddy runs a Merc 30, both four strokes. They are identical, with the only difference being a different computer modual.


So one of you too paid too much for the same motor....shocked.gif

It's not that simple, most of the outboards share same block size and heads, the carburation/fuel injection is the difference.

If you check any V6 they all have same CC size, but they vary from 150hp to 250hp.

Share this post


Link to post
Share on other sites
  • 0
delcecchi

This was on the Merc. web site.

Quote:

EPA regulations prohibit changes to engines that could affect emissions limits. Per the service manual, "The dealer and/or consumer is not to modify the engine in any manner that would alter the horsepower or allow emission levels to exceed their predetermined factory specifications." The only changes permitted are carburetor jet and gearcase/gear ratio changes for high altitude operation as detailed in applicable Mercury Marine Service Manuals


Share this post


Link to post
Share on other sites
  • 0
JohnMickish

I'm sure that even though the block and head is the same, the cam would be different, along with the injector(s), fuel rails, probably the piston(s) and intake as well as the ignition and fuel programming. You don't just get a 25% HP increase with a programming change.

Share this post


Link to post
Share on other sites
  • 0
Ray Esboldt

I looked into mods on my 90 Optimax to make it 115. All it took (allegedly) was 115 injectors and a 115 computer. However, that was to the tune of about $2000, and the motors warranty would be voided. I suppose once the warranty expires I could try to find a junked 115 Optimax for parts.

I still think Cretliner should have rated the 1850 Fish Hawk tiller for 115.

Share this post


Link to post
Share on other sites
Guest
This topic is now closed to further replies.
Sign in to follow this  



  • Your Responses - Share & Have Fun :)

    • Bigfatbert
      Thanks Cliff for your Pike River deteriorating ice reports and pics . I. Really want to show my wife the hatchery when the action is really happening this year , I would assume you will be right on that when this happens , is there any way that you can give a shout out on here as to just when this scenario is happening up there . With the warmer temps being quite steady now , I would think the run will be rather strong this year when things get going ..  
    • biff
    • CigarGuy
      I got the 4 smaller ones the other day. They are a little over 2" long and paid only $6.64 total to my door.  The quality seem pretty good, we shall see once I put them to some use! 
    • Bryan P
      Thanks Leech! Ya you need a life jacket in a kayak. I have mine behind my seat, but Yes I should be wearing it. 
    • leech~~
      Nice video! Life jackets not needed in Yak's?  Just asking.
    • Fish Head
      Cigar guy, you got a good deal. They look like size 7 which is what I use the most for summer walleyes. Fleet Farm had all Rapalas 25% off last week so I stocked up.  I've used them a lot in the last 2-3 years.  If you fish them on rocks... you will lose some.  I try not to use them over the real bad snaggy stuff but sometimes I still do and usually end up losing one.  It takes a little practice, but they work well when you get it down.  
    • Fish Head
    • Fish Head
      Funny, I first heard of this on LOTW also about 8-10 years ago.  They're tasty but honestly I often forget about doing it. 
    • Bryan P
      Finally warm weather has arrived in Minnesota and I decided to hit the river for the first trip of the year in the Kayak. Felt good to be on open water after a very long winter. Even managed a few rough fish to get warmed up for the year!  Video: https://youtu.be/0gYDiOVH3As  
    • monstermoose78
      Spending some time in the turkey blind as it’s on solid ground. Had some jakes behind me but they don’t want to play. It’s okay as the have a free pass for now. In a couple weeks they will not have a free pass. If they would have come out I would have taken some photos. Lots for noise as everything is excited by the warm weather.