Corvair engine with Ellison EFS3-A throttle body running on Roy Szarafinski's dynamometer. This dyno is instrumented with O2 sensor to read fuel-air mixture, EGT, MAP, etc. and can put any desired load on the engine so torque and HP can be obtained.

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Comment by Brian A Manlove on January 20, 2015 at 8:57pm


The front of the pulley comes off and Dan's system replaces that with a "drive dog" that has 2 drive pin holes.  The steel drive pins thread into the harmonic balancer's threaded puller holes.  They get a pretty tough rubber sleeve over them that is O.D. sized to slip fit into the holes in the drive dog.  No belts to worry about, pretty much rubber-cushioned drive, extremely accurate bracket & parts, and very reasonable price.  He sold me the mounting kit only, or you can buy the whole enchilada with the alternator and everything.  

The only down-side is slightly less output at idle because with the belt drive, you're getting higher RPM at idle due to the pully on the alternator being smaller than the pully on the prop hub.   

Comment by Bryan Walstrom on January 20, 2015 at 8:13pm

Awesome! I am considering the 110HP option myself. What do you think of the rear alternator setup? I was just reading about this option with a coupler. Is it similar maybe to like a jet ski to the impeller with a sort of "cog into cog rubber bushing?"

Comment by Brian A Manlove on January 20, 2015 at 7:31pm

Bryan - it's 2700 cc 100hp.  On Roy Szarafinski's dyno we calculated it at 97 hp @2850 rpm, but according to Roy it will gain a few hp after it is completely broken in.  Right now I've got a total of maybe 40 minutes of run time on it.

I have also since then changed the alternator to a rear mount direct-drive using Dan Weseman's rear alternator mounting system, so I think that will potentially reduce load a bit with no belt/pully drag.

Comment by Bryan Walstrom on January 20, 2015 at 8:24am

Video won't play for me at the moment... which HP option did you build and what actual HP does it produce?

Comment by Mark Maltais on August 11, 2014 at 7:48pm
Wow! Smmmooooootthhhhhhhh!
Comment by Paul on August 11, 2014 at 12:08pm
It's alive! Great to see that Brian. When do you think you will be ready for first flight?

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