Chainsaw Repair

How To Basics - Carb Fixes + Mods - IPL and Service Manuals => How To Basics and Fixes => Topic started by: 1manband on September 26, 2016, 08:30:51 pm

Title: HP motor potential/comparison tool
Post by: 1manband on September 26, 2016, 08:30:51 pm
...as it says.

opens in libre office or other spreadsheet type program.

-lets you compare one or two motors.
-lets you verify reasonableness of HP clams and/or potential.
-helps to see what is going on with geeky engineering terms.  hahaha.

hope it helps
-joe
Title: Re: HP motor potential/comparison tool
Post by: 1manband on September 26, 2016, 09:07:10 pm
the way it works, all that needs to be input is three things: stock rpm and hp and lastly motor size in cc. 

it calculates things like bmep, cfm, and some efficiencies.

there are some ranges that the numbers fall into.

then you can type in a new hp value for the same motor, and see if it can happen.

...if the new hp you want out of it is within these ranges, chances are it will work.

possibly more digital garbage.  this stuff helps me learn, hope it may help someone else as well.

Title: Re: HP motor potential/comparison tool
Post by: 1manband on September 28, 2016, 08:37:36 pm
jack kane's  web site reference material was used for the quick program. good stuff:  http://www.epi-eng.com/piston_engine_technology/volumetric_efficiency.htm

ranges used came from bsfc of the leanest stock saw i could find, and a saw used in prof. blair's book; ve from book as well.

a screenshot of the program follows:  (about the most that could be added was about 2 hp for this jonsereds 52, before it goes outside one of the ranges).
Title: Re: HP motor potential/comparison tool
Post by: Chris-PA on September 29, 2016, 08:44:53 pm
Hey Joe - I downloaded it but it will likely be a few days until I can look at it.  Looks interesting from your description.