1972 evinrude 65 horse performence tips?

[MonsterDan]

Hi I hope I am putting this in the right place here being a newb and all, I have a evinrude 65 horse 1973 and it runs really well and I was wondering if there are any ways to squeeze a little more power out of it, any ideas or tips would help, also would it be alright to run high octane gas ? any info would be great Thanks!

 

[durban]

Re: 1972 evinrude 65 horse performence tips?

i would increase the piston to next oversize , not many people will agree with me on this one : i would advance the timing by 2degrees ,it does give you 2hp extra so they say they say if you go more than 4 degrees then you looking for trouble , make the flywheel a little bit lighter . put some trim tabs on the back of your boat , then you should be flying , cheers
some info here about air\fuel
http://www.enginebasics.com/EFI Tuning/AF Ratio Basics.html

 

[Faztbullet]

Re: 1972 evinrude 65 horse performence tips?

Oversize boring adds very little if any hp to a 2 stroke motor....... leave the timing alone as you have the points system. The best way to get about 5-8 hp from motor is find a cylinder head off a mid 70's Stinger as the chambers in head are smaller and will add about 10-15 psi compression. It take about 5 hp to increase speed 1 mph...

 

[jimmbo]

Re: 1972 evinrude 65 horse performence tips?

Proper prop, engine height, trimming will go long way to improving performance. Removal of unnessesary ballast from boat. So get rid of the Wife, mother-in-law, kids, etc. Mistresses and Girlfriends are not considered ballast.

 

[MonsterDan]

Re: 1972 evinrude 65 horse performence tips?

Oversize boring adds very little if any hp to a 2 stroke motor....... leave the timing alone as you have the points system. The best way to get about 5-8 hp from motor is find a cylinder head off a mid 70's Stinger as the chambers in head are smaller and will add about 10-15 psi compression. It take about 5 hp to increase speed 1 mph...

Thank you, this sounds like something I would like to do, it looks like if i can find a mid 70,s head for a 65 stinger it should bolt up like the original?

 

[F_R]

Re: 1972 evinrude 65 horse performence tips?

Be careful. Messing with timing and compression can lead to pre-ignition and blown pistons. Besides, unless you are into competetive racing, you won't be able to tell much if any difference.

BTW, there are no breaker points in that motor.

 

[boobie]

Re: 1972 evinrude 65 horse performence tips?

You beat me to the no breaker points F_R.

 

[MonsterDan]

Re: 1972 evinrude 65 horse performence tips?

I finally got around to doing some general tune up things on my 72 evinrude 65 horse water pump impeller,rectifier, spark plugs and i put some new coils on it also got the carbs synced up and tuned in. fuel filters cleaned and changed, changed the lower unit oil/lube ( no shavings ) .. I thought it was running good before now it runs great and I have come to the realization that if i want more power the best thing i can do is upgrade to a larger motor. I got the stuff today to install a tell tale, i cant wait to get that done, is there any thing else i should look into as far as tune up ? Thanks !

 

[boobie]

Re: 1972 evinrude 65 horse performence tips?

You did good, now run it.