Curious

[gudu59]

"Hi I have a 1992 johnson 20hp

"Hi I have a 1992 johnson 20hp crend and was wondering if I changed my carb to say a 25 or 30 which looks as if they would fit would that improve the performance or just make it use more fuel,thanks for any help.Regards Nick."

 

[galamb]

"You would have to do more res

"You would have to do more research to see what else may be different - they may or may not have shared a powerhead - if the displacement is different, you would only succeed in flooding the cylinders.

Other differences (if the powerhead is the same) could be the leaf valves (reeds), possibly the exhaust plate etc.

Some motors can be easily modified to higher horsepower but in all cases they WILL burn more gas and WILL NOT produce enough of a performance increase that you can actually notice, unless you lie to yourself....

Going from 20 to 25 horses = 2 mph at wide open, on calm water with no wind - 20 to 30 may get you 4 mph (but probably closer to 3.5)...

Hardly even worth the time to make the changes, must less the cost of parts - in my opinion.."

 

[outboard_doctor]

i agree with graham for the co

i agree with graham for the cost and little improvement it wouldnt be worth it.

 

[gudu59]

"thanks guys that answers it a

"thanks guys that answers it all for me,
Regards Nick."