getting more hp out of a 59ci merc????

[fs5]

just after some info on what you can do to the 59ci mercs .
i seen a lot of you guys are running the 40hp's on tinny's over there in the states .
i run a 55 seapro (pretty much same as a 60hp) on a slt boat over here.
the motors pulled apart at the moment and getting rebuilt and while its apart i wouldn't mind seeing if i can get a few more hp's out of it.
any thoughts??
i have heard of guys building tuners and porting the reed blocks???
since they don't have heads ,dose shaving some off the crank case help???
have heard it works on the mercs..

any help appreciated

[Fast Fred]

dose shaving some off the crank case help??? no:cool:

you can put a bevel on the exhaust port, you can flute the piston crown in front
of the intake ports. or you can pull the sleeves and replace with ones with a higher port map. not the best one to start with, but if thats what you got:eek::cool:

[genea01]

can take a pic of ur motor and put it on here never seen a 55 sea pro:cool:

[fs5]

here's a pic

[genea01]

do you have a side pic, and how fast and rpm's are you running on that boat looks like fun.

[fs5]

do you have a side pic, and how fast and rpm's are you running on that boat looks like fun.

nah gene ,i don't have a side pic .have few of different trim and engine heights.
the prop i have at the moment measures 21.35p and is 11 d .it turns anywhere from 5400 to 5900 depend on how the water is and what mood i'm in.
heres a vid, it runs low to mid 60's
http://www.youtube.com/watch?v=nZD8SHnl-7M

[Fast Fred]

jack it up! till the prop shaft is even with the speed toob valve center.:cool:

[fs5]

jack it up! till the prop shaft is even with the speed toob valve center.:cool:

thats a pic of when i first set it up .the motor sits about 50mm off the transom now.it stops sucking water if i hold flatout for too long .

[50hptiller]

nice video, u got a low water pickup? what year is you motor? gear ratio? 3 holer? it sure looks a lot diff than our 59's, that y i am askin the dumb ?'s

[fs5]

no low water pickup .
the old girls a 2000 model and apperently was still pretty smick inside after i turned it upside down.
its a 3cyl and runs the same 1.64 to 1 ratio as the 60 mers do
theres no dumb question mate when it comes to talkin about boats ,i reckon i could chew anyones ear off

mate i just watched your vid in your sig,you wanna swap !!

[genea01]

well have you done anything to your motor yet keep us posted on what all you have done i would get low water pick up and then start leaning motor out a little from stock but watch your plugs, that is a cool boat like the video

[fs5]

its all going back together stock as....
i've been after a low water pick up for a while now ,but i still need to get a good prop to run.i need a decent 12 in diameter around 20p to get the most out of the extra height.
i've got my eye out around the place for a decent block to have a fiddle with.
are the 40hp blocks the same as the 60hp ?

thanks again for all the replys and pm's

[Fast Fred]

40 hp is Not the same, ports are different. there are things you can do to make it GO. there are other flavors that will give more bang for your efforts, and them other flavors Will run right a round you. a mod 59 Merc puts the hull in "X" class,
you would need to get 50 more hp out of the 60hp just to stay up front.:eek:

be best to make some dome pistons for it, bevel the exhaust port, flute the pistons in front of the intake ports, shortin the tuna:eek::cool:

[50hptiller]

how much does that hull weigh?

[fs5]

40 hp is Not the same, ports are different. there are things you can do to make it GO. there are other flavors that will give more bang for your efforts, and them other flavors Will run right a round you. a mod 59 Merc puts the hull in "X" class,
you would need to get 50 more hp out of the 60hp just to stay up front.:eek:

be best to make some dome pistons for it, bevel the exhaust port, flute the pistons in front of the intake ports, shortin the tuna:eek::cool:

thanks mate,i'l hunt around for a 50/60 block to fiddle with.

is it worthwhile to flute the piston's and bevel the ex ports and cut the tuner ,on a stock build?

[fs5]

how much does that hull weigh?

75kg ,

[genea01]

yes it will help, keep us update on the breakin and how the rpms are now

[lcp]

hi everyone,any lead where can i get domed piston for the sea pro 55,or maybe someone is making them.best regard Mr Lo.