Michael,

I'm not sure what you mean by "...can easily be tweaked to hit 300".  Maybe with nitrous, but I think the question to ask is at what rpm, and at what cost to reliability.  With the gearboxes available, we're limited to about 7500rpm for takeoff and 6000rpm for cruise.  I don't think you'll get anywhere near that hp at 7500 without adding a turbo. A peripheral ported 13b should easily produce 250 hp at 6500.  You'll have to spin it much faster to get to 300hp.  If you want some serious hp, peripheral-port a 3-rotor. 

 

Some of the things I like about the 20B are:

  Three power pulses per rev. (same as a 6-cyl. 4-stroke engine)

  Sound is more pleasing to the ear (subjective)

  One extra rotor - you'll hardly notice it if one rotor goes south

  Two extra spark plugs (have you heard about "SAG"?)  SAG is less of an attention getter with three rotors.

  There's no replacement for displacement!

 

My 20B Lancair ES looks to be about 75-100 lbs lighter than the 6-cyl. Lycoming powered ES's.

 

[Lynn, did I get the numbers right?]

 

On 3/6/07, Michael McMahon <michael@aeromotogroup.com> wrote:

I think I'm going to buy the used 20b I posted about a couple weeks ago.  But over the weekend I read that a stock Renesis engine makes 250 hp and can easily be tweaked to hit 300.

 

So my question, before I commit myself to the 20b, is whether people recommend bumping up the horsepower slightly on a Renesis (lighter engine so less hp somewhat offset by weight reduction) rather than using a 20b.  I haven't seen any recent discussion on this and couldn't find anything in the archives, but I'm sure it was covered at length at some point.

 

Is the Renesis a candidate for an ES?

 

Thanks,

 

Michael McMahon

Lancair ES