Small Engines (Lawn Mowers, etc.): Briggs&Stratton engine technical information, combustion chamber volume, briggs stratton engine

Question
Hi.

I am currently designing a Roots Blower to be used as a supercharger on a old Briggs&Stratton INTEK™ I/C® 10hp engine. In order to simulate the effects of the device and create the optimal design I need to model it. I require some additional information regarding the engine to that available on their website to do so. I’m looking for;

-The engine speed range
-The valve diameters
-The valve lift values or cam profiles
-The pressure limits of the engine
-The crank radius

Thank you for your time.

Answer
Most of the information you are looking for will have to be measured.  I would check the link below as it will have some crank information:

http://www.smalleng.com/linked/briggsspec.pdf

Engine speed:  Rated to 3600R RPM
              Real world experience, should be able to support 5000 RPM.  Have spun a 5 HP up to 14,500 RPM, once, for about 1/2 second before it exploded.

Valve diameter:  No specs published, measure
Valve lift:  No specs published
Pressure:  No specs.  Would calculate based on head bolt diameter and combustion chamber volume
Crank raduis:  On engine chart/link

Some of the racing sites have info for the popular engine, usually the 13 cubic inch blocks, aka, 5HP.  Did you search the web for Briggs and Stratton Racing engines?

You will have to lower the compression ration to use the blower.  I have seen thicker head gaskets, or use two head gaskets, drill holes in the piston and other various techniques to lower the compressiont ratio.

Do you have any pictures?

Eric