mercruiser 3.7L upgrade help

[knied1]

I currently have a 2 bl carb in my boat, but i have an engine with 4 bl in my garage, was told that one of the cylinders on the motor in my garage is blown.

This being said i am thinking about swaping out the carbs so that i can bring the boat from 160 hp to 190 hp. This looks to be an easy swap, pull carb and head from one and put it on the other. Do you know if it is that easy, or do i have to swap out cams, fuel pump etc?

what i am looking to do is gain a little more power, last year we had 4 adults on the boat, and 1 tuber, and it seemed to be just a little too underpowered, By boat is a 1988 stingray 210svc, dry weight is 3200.
since i already have all the parts this upgrade should only cost me a new head gasket. Do you believe i will realize an increase in power, or just an increase in fuel usage?
Any help you can give will be greatly appreciated.

 

[Bondo]

Re: mercruiser 3.7L upgrade help

This being said i am thinking about swaping out the carbs so that i can bring the boat from 160 hp to 190 hp. This looks to be an easy swap, pull carb and head from one and put it on the other. Do you know if it is that easy,

Ayuh,... It should be that Easy,... 30hp is Very noticable....

 

[knied1]

Re: mercruiser 3.7L upgrade help

I was a little curious and started to pull th carb off the engine in the garage. It does seem easier than origionally expected. i was able to pull off the intake manafold, and leave the carb mounted to it. I did notice that the oil filter is mounted on an assembly vertically, and the one in the boat is mounted horizontally, should i pull the assembly, swap them too?
I was also wrong in the origional post the 2 bl specs at 170HP, and the 4 bl is 190HP so there will be a 20 hp gain, will this be worth the increased gas milage, and does any one know how much of a fuel usage increase i should expect?


thanks again

 

[ardieski]

Re: mercruiser 3.7L upgrade help

Did you inbetween made the upgrade of the engine? I?d like to know your results. More Power? More fuel? Is it worth to do it?

Carsten, Germany

 

[QC]

Re: mercruiser 3.7L upgrade help

Welcome aboard ardieski. This thread is almost three years old. I just checked and this member hasn't posted for over a year, and he was considering a repower. We close older threads like this to help keep things focused. We'd really like to help out though, so please post a new thread regarding your specific engine. Be aware though, the 3.7 has been somewhat confirmed as a troublesome engine, and most would consider it a better candidate for a complete repower. Good luck!!