help! engine rebuild

[wesley pipes]

i have a 92 90hp vr johnson i luckly found out that was blown! the compresion checked out fine but when i pulled the heads you could def feel bad spots in the walls. i knw how to rebuild i have done a few befor but i want to know what can i do internaly to get this thing runnig badass? i have heard of reed valve replacments, and tunning the exhaust not to mention jetting the carb. i dont have alot of money to spend but i am doing all the labor myself. does anyone of yall know what i can do or a place to go and check all this out for myself? i want to be able to have this thing in the water by the end of the month thanks!

 

[tashasdaddy]

Re: help! engine rebuild

first buy an OEM Johnson manual. outboardbooks.com or ebay.

 

[Mas]

Re: help! engine rebuild

Getting it properly tuned will make it run "badass!" I personally would not change the factory set up. If you want more HP, get a bigger motor. I do not think you'll be happy with "bolt-on goodies."

MAS

 

[wesley pipes]

Re: help! engine rebuild

yea i know just get a bigger motor. but i dont want to do that. i want to build this one with more kick to it then just a 90. i know how to do all of it i need to know what to do. ive rebuilt at least 5 4cyl motors befor i just want to know about adding performance parts. not just like a bolt on but internall also. right now the block is sitting in my garage as i wait for the rain to stop and its going to be bored .30 over on all cyl.

 

[ezeke]

Re: help! engine rebuild

You will need the larger intake and exhaust ports like the 115.

 

[Dhadley]

Re: help! engine rebuild

We'll assume you're going to bore it .030 over. Going .30 over would be a bit much. There's a ton of potiential in a stock intake.

 

[wesley pipes]

Re: help! engine rebuild

yea i know but 2 cyl need to be bored due to an overheat so im going to do them all. and im already in the process of trying to find the "bubble" back exhast like on the 115-140 hp's. ive seen it done befor on drag boats and racing mods. im not looking to beat any competition (except the ocasional boater that wants to brag to hard) i just need to know what else. thanks

 

[JB]

Re: help! engine rebuild

When you start yabutting Dale Hadley on modifying a JohnnyRude for increased performance you are well along the road to disaster. If there is anyone in the world you need to heed it is DH.

 

[wesley pipes]

Re: help! engine rebuild

ok the cyl will have to be bored or i have to buy a new block and im not buying a new powerhead when i dont have the money and i can build my own.

 

[renegade15]

Re: help! engine rebuild

This place also has composite reed valves that claim to boost performace. Might be a place a place to start.

http://www.chriscarsonmarine.com/reed-valves.htm