flyrotary@lancaironline.net Mailing List Archive

Michael,

It depends on what RPM you can use. The Renesis only makes that kind of power between 8500-9000 RPM.

You would need a 3:1 psru at least. The 20b will produce 250 HP at a much lower RPM and lower stress level. Al G dynoed his 20B at 295 hp @ 6800 RPM if I remember correctly. (might have been 285) Al chime in if you see this. The 20B is 50% bigger. (or 1/3 if you prefer) The engine simply doesn't have to be as highly stressed to produce power. For the ES GET THE 20B! It's still lighter than the 550 and will be easier to balance. Even with the rotary the old saying applies; There is no substitute for cubic inches! Provided that the engine will FIT in the airframe. This isn't a problem with the 20B. The ES is set up for the 6 cyl so you would have a reasonable job fitting the 20B in. My $.02

Bill Jepson

-----Original Message-----
From: michael@aeromotogroup.com
To: flyrotary@lancaironline.net
Sent: Tue, 6 Mar 2007 2:20 AM
Subject: [FlyRotary] 20b vs. Renesis for Lancair ES?

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

AOL now offers free email to everyone. Find out more about what's free from AOL at AOL.com.