25 hp tricked out to 40 hp

F

FLBert

Cadet
Joined
May 23, 2009
Messages
17
How dose someone trick out a 25 hp evenrude outboard to have 40 hp?

The reason I am asking is that I found a boat I might buy and this is what the ad said. I was wondering if it was bored out to the max or if there is another trick.

Thanks
 
R

restornator

Petty Officer 1st Class
Joined
Aug 15, 2009
Messages
361
Re: 25 hp tricked out to 40 hp

yeah right!

I one saw a 1972 20hp Johnson that was claimed to be 35hp after adding a 35hp carburetor to it, despite the 9 cubic inch dispacement dfference...
 
C

catalyst-519

Seaman
Joined
Mar 12, 2008
Messages
64
Re: 25 hp tricked out to 40 hp

I know that in older 9.9's a simple carb upgrade will give you a 15hp. Everything else is identical. Other than that I would be skeptical that you could acheive the same results on a larger motor.

Don\t believe the hype
 
M

mudslinging79

Petty Officer 1st Class
Joined
Jun 18, 2008
Messages
374
Re: 25 hp tricked out to 40 hp

i have a 35 horse cover you can put in your 18, bumps it up to 35... you would have to swap engines for that kind of horse power.
 
Bob_VT

Bob_VT

Moderator & Unofficial iBoats Historian
Staff member
Joined
May 19, 2001
Messages
26,022
Re: 25 hp tricked out to 40 hp

It really does not happen....... get a 40 and put the 25 cover on it is the shortest route......... they are totally different so it may require duct tape
 
M

mudslinging79

Petty Officer 1st Class
Joined
Jun 18, 2008
Messages
374
Re: 25 hp tricked out to 40 hp

THATS WHAT ALL THE TAPE WAS FOR!!! couldnt figure out why i lost so much power...
 
Cofe

Cofe

Lieutenant Commander
Joined
Apr 23, 2009
Messages
1,883
Re: 25 hp tricked out to 40 hp

I don't think you could get 40 hp. unless you use nitrous and have a basket ready to collect parts.

Anyhow here is a interesting link on some mods. http://forums.iboats.com/showthread.php?t=274566

Boring does not do that much for hp increase on a outboard. Having your motor tuned and trimmed for your boat will be the best package for speed.
 
Tim Frank

Tim Frank

Vice Admiral
Joined
Jul 29, 2008
Messages
5,333
Re: 25 hp tricked out to 40 hp

FLBert said:
How dose someone trick out a 25 hp evenrude outboard to have 40 hp?

The reason I am asking is that I found a boat I might buy and this is what the ad said. I was wondering if it was bored out to the max or if there is another trick.

Thanks
Click to expand...

I think the key word is "trick"...:D ;)
 
F

FLBert

Cadet
Joined
May 23, 2009
Messages
17
Re: 25 hp tricked out to 40 hp

Thats what I thought. I know that on smoe outboards (john/rudes)you can change the carbs to bost the preformance and in some cases the exhaust, as in the 9.9 to 15 hp. Without duct tape;). I thought it was a crock. I just wanted to check.

Thanks for the chuckles
 
kenmyfam

kenmyfam

Supreme Mariner
Joined
Aug 10, 2006
Messages
14,385
Re: 25 hp tricked out to 40 hp

More HP = Bigger motor
My 2 cents
 
F

FLBert

Cadet
Joined
May 23, 2009
Messages
17
Re: 25 hp tricked out to 40 hp

Well, after reading the link that Cofe posted and talking with my brother in Georgia. One could actualy come close to a 40 hp out of a 25 hp. With boring it out to the max gaining around 3 hp and puting a 35 hp carb plus a little trimming out one could get around 38 3/4 hp. course it would be wise to change the lower unit as well and adding a little more 2-cycle oil to the gas then normal.
:redface:
 
kenmyfam

kenmyfam

Supreme Mariner
Joined
Aug 10, 2006
Messages
14,385
Re: 25 hp tricked out to 40 hp

FLBert said:
Well, after reading the link that Cofe posted and talking with my brother in Georgia. One could actualy come close to a 40 hp out of a 25 hp. With boring it out to the max gaining around 3 hp and puting a 35 hp carb plus a little trimming out one could get around 38 3/4 hp. course it would be wise to change the lower unit as well and adding a little more 2-cycle oil to the gas then normal.
:redface:
Click to expand...

And the reliability factor is ????:eek:
 
Cofe

Cofe

Lieutenant Commander
Joined
Apr 23, 2009
Messages
1,883
Re: 25 hp tricked out to 40 hp

kenmyfam said:
And the reliability factor is ????:eek:
Click to expand...

I agree Ken.
I wonder what kind of resale value a "tricked" out motor would have? Who would want to buy one?:confused:
 
A

Al-53

Chief Petty Officer
Joined
Jul 17, 2008
Messages
491
Re: 25 hp tricked out to 40 hp

I will say this..the trailer is sorta short....may have been a tricked out jet ski trailer...lol....has to be some stress on the eye hook..hope it never lets go...and trailer bounce also...wow.....

Al
 
Lion hunter

Lion hunter

Lieutenant Commander
Joined
Apr 9, 2005
Messages
1,529
Re: 25 hp tricked out to 40 hp

I gotta trick. I can turn a dollar into a nickel. Send me a buck and I'll show ya. :)
 
D

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: 25 hp tricked out to 40 hp

It simply amazes me that the guy stopped at making 40 hp out of his 25. Since it's just a simple carb swap you'd think he'd have grabbed some 100......no, 200 hp carbs. Now we're talking trick!!
 
1946Zephyr

1946Zephyr

Vice Admiral
Joined
Oct 21, 2008
Messages
5,556
Re: 25 hp tricked out to 40 hp

What year 25 are we talkin here? If it's the '76 and older model, fuggitaboutit. Won't happen, unless you do serious mods to the engine. The 77 and later 25's were 31.8 cubes and were easily converted to 35hp, by changing carburetion and intake manifolds. As far as 40 hp......uhhhhh no.:(
 
You must log in or register to reply here.
Top