upgrading a 9.9 electronic ign,with a 15 points ign,carb and exhaust

[jrdplowing]

can I use the carb and exhaust tube from a 1975 15hp rude,to use on a 1985 9.9 with electronic ign to up the hp,are they the same exept for the ign or what else do I need if anything to achieve the 15 hp from the 9.9,thanks for any info

 

[F_R]

So you want to put points ignition on your 1985 9.9? Bad mistake, even if it fits. Those 9.9/15's of that era were trouble from the get-go.

 

[jrdplowing]

if you read the post I want to make a 15hp out of my 1985 9.9, using my 1975 15hp, usually from using the carb and exhaust tube,are the 2 yrs compatible enough to do it

 

[raczekp1]

yes.all parts will fit(carb, exhoust). but CDI ignition is much better then points ignition

 

[F_R]

if you read the post I want to make a 15hp out of my 1985 9.9, using my 1975 15hp, usually from using the carb and exhaust tube,are the 2 yrs compatible enough to do it

I did read your post, and you indicated you wanted to swap the ignition, which I cautioned against. Really doesn't matter because I doubt it will fit anyway. The crankshaft probably is different. But I'm not inspired enough to check it out. Many of these grey hairs I have came from fighting those early 9.9/15hps, some of which wouldn't run for one weekend.

Have fun and don't kill the messenger.

 

[kbait]

Don't change exhaust tube from the '75.. they didn't have 'tuned' exhaust upgrade on 15's until about '80. Don't change ignition, as stated above, the points ignitions on those motors wasn't great, and the 9.9 cd ignition you have is exactly the same as a 15hp ignition. Change the carb only, and you'll see much more top end power, and it'll still idle down nicely..

Good luck!

 

[jrdplowing]

I just read my first post and it only states that, "can I use the carb and exhaust from the 1975 15hp", I know not to go backwards and change electronic ign to points, but lets move on thanks for all the help,and for info on these motors I have used them for over 30yrs and never had a problem with either of them,just wanted to get a little more top end from a 9.9 with the better ign, thanks again, so for the best upgrade I take it that I would need the exhaust from a 1980 or later 15hp

 

[tomhath]

You might gain a couple of HP at WOT; the 15hp motors were rated at 5500 RPM while the 9.9 were rated at 5000 RPM. At anything below WOT the two motors will have the same power because you're not gaining any torque.

 

[jrdplowing]

thanks,tomath,JRD