1979 Johnson 70hp 3cyl. Excellent cond. hood is removed! maintenance and upgrade tips please!!!!!?

I'm 15 and I LoVe my Boston Whaler. It's a 1975 15ft. Whaler Sport. My father let me use his alumnacraft last year. He gave it to my uncle for his house up north, leaving me without a boat. All my neighbors and practically everyone in our yacht club have whalers. Ironically, our neighbors were selling theirs so my dad bought it for me! I love engines n high performance. Alot of people on our lake have smaller whalers, mostly 13 footers with 25-50 hp motors on them. not mine! I got 70! The kid's like to race eachother and stuff. People always made fun of my crappy tin boat. But im more respected with my whaler. I recently installed a whale tail stabilizer fin. Now its really fast. tops out at 48mph. So far I have the fastest whaler. I've never lost a race with it yet.



In a few weeks, I'm going to take it out and restore it.

- redo the wood finish



- add seat cushions



- repaint the motor.



- new/larger "whaler" decals



- 4blade speed prop



- what about engine upgrades??1979 Johnson 70hp 3cyl. Excellent cond. hood is removed! maintenance and upgrade tips please!!!!!?
Thats a great old engine, I would strongly advise against trying to modify it, marine engine rebuilds are pretty expensive and boat motors are already built to high performance standards anyway.

It can be done but it would be cheaper to buy a bigger engine if you want to go faster.1979 Johnson 70hp 3cyl. Excellent cond. hood is removed! maintenance and upgrade tips please!!!!!?
Tere isnt much restriction on a stock boat motor but it could help a bit at high speeds.

Make sure water cant go straight into the carbs if you are running in rain.

It is gonna be noisier, I suspect there will be a pronounced waahhhhh as you open the throttle up.

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1979 Johnson 70hp 3cyl. Excellent cond. hood is removed! maintenance and upgrade tips please!!!!!?
dont worry, i never drive it in the rain.

but as I go faster, more clean air from the outside will be pushed into the carbs as the carbs suck the air in, instead of the carbs sucking in air contained under the hood.

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Since air flow to the cylinders is greatly increased, I'd need to increase the fuel flow as well, right? If so, how can I do that?

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