1981 115 Mariner inline 6

[don]

I have a 1981 115 hp inline 6

I have a 1981 115 hp inline 6 Mariner...from what I've read the specs are identical for all these motors from 75 hp up to 140...what is the difference? What can I do to my 115 to increase the hp? This 115 seems to run very strong for a 115.

 

[Kirk Spradling]

" Don,

Unfortunately, it is

" Don,

Unfortunately, it isn't as easy as just bolting on a set of 140/150hp carbs. The porting in the block is different. The bore and stroke on the 90 thru the 150 are the same. The porting makes the difference. Besides, I would bet that the pulling power is just about the same on each motor. The higher HP engines usually get theirs at the upper end of the RPM scale and unless you are just about going fast, you probably aren't going to gain much.

You might want to check over at the scream and fly forums (forums.screamandfly.com) to see what others have to say.

Good luck. If it was easy, we all would have 1500s instead of 1150s...

Kirk "