looper crossflow ?

[cookbayou]

Ive heard the terms looper and crossflow alot when used to describe a johnson or evinrude. What are they? And whats the difference?

 

[mrcj001]

Re: looper crossflow ?

In simple terms:

Crossflow engines take the fuel mix thru the combustion chamber by the intake ports then flows accross the top of the piston and out of the exhaust ports. To clear the combustion chamber of burned gases a deflector type dome on top of the piston is nessesary to deflect the charge up and around the chamber.

Looper engines use a flat top piston. Three intake ports are slanted upwards and facing each other. This directional force effect causes the incoming charge to impinge on one another and flow upward and around the smooth domed piston then down and out the exaust ports on the adjacent side on the cylinder wall. The results in a clean and powerful charge.

Just my opinion, a 70 horse looper has as much torqe than a 115 crossflow

 

[ezeke]

Re: looper crossflow ?

Bill Kelly has a good article on this subject: http://www.maxrules.com/fixtheory2.html

 

[DJacksonRN]

Re: looper crossflow ?

That was a really good summary of the difference. I had been wondering the same thing. Thanks!