As requested.... different airplane, but same engine so those of you considering going ELSA might be interested in this...
When I bought my RANS it had a 100hp 912uls. Performance was really good considering I live at 6650ft elevation (plane weighed 693 empty then)... but my home strip is 1600ft of dirt and I wanted to be able to fly out of here at gross on a hot day and not be dodging the power lines (at one end, two story house at the other). I also wanted to do some other modifications that would add a few pounds etc.
I called and worked with Jay http://zipperbigbore.com/ to get my kit on the way. He was a pleasure to work with, and we still keep in contact. There are several options of kits, and my RANS builder friend who knows Hal and the history on the setup gave me a little back info which was all positive towards the 1484cc versions. The really big bore 1622cc version requires case machining and I was told there had been some issues with that version they were still possibly working out.
Anywawy, the kit came quickly and I got to work. It's a pretty easy/straight forward install. Took a day to do, not being in a rush. They give instructions and info on break in etc. All pretty straight forward. The kit knocks like 4 lbs off you engine. The CNC cylinders have better cooling they say, but I have no data to argue that either way.
I knew there was a pretty good increase in power right off because I had to add a couple degrees to my prop (68" 3 blade taper tip warp drive at the time) to get the RPM back in a similar area. Take off roll was shortened quite a bit, and climb went up 300 ft a min easy, maybe more.
I already had already installed a wideband o2 gauge in the plane, and a hacman leaner and 1 egt. Since then I have installed some MGL avionics instruments, 4 egts, CHT, some other stuff etc.
I also added a Rotax airbox and did some custom intake stuff. I've actually had several different intake setups, but that's not really related. Anyway.. when I started modifying the exhaust is when things got interesting. But that is also not really related to the zipper kit.
Anyway, I felt I wasnt taking full advantage of the zipper with the small-ish prop, so I bought a 72" KOOL Scimitar 3 blade prob. They are light for their size, have leading edge protection and are fairly affordable.
But to do that, I had to put larger tires on...which I wanted to do anyway, as I enjoy the off airport stuff. So I had to modify the nose fork to get a 16.5"x6-6 tire there, and I have 21x8-6s on the mains now. This gave enough clearance for the longer prop. The prop gave another 150 fpm in climb. I have it pitched real fine for take off and climb now. The plane at around 1025lbs take off weight will get airborne in about 200ft or less at 6650ft field elevation by grabbing a handful of flaps and yarding it off the ground at 40mph. I have seen as good as 1200ft / min climb at a very steep angle (60mph) at that same weight between 7500-8500ft altitude. I can't imagine what a monster it would be at sea level.
Probably the most amazing and somewhat unexpected change has been economy. The slightly higher compression is probably mostly responsible for this. But even dragging this big tires through the air on a plane that is nowhere near as clean as the CT's I see ~3.75gph at 110+mph indicated cruise. And this is at 5500ish rpm. I have slightly larger main jets in my carbs right now, as somewhat of a precaution because even though the carbs adjust somewhat for altitude, I'm not taking my chances until I can visit low altitude and see for myself.
Anyway, it starts good, runs smooth, gets good economy, makes good power, is lighter, and really I don't have anything negative to say about the setup. It costs some bucks, but I don't know how you get could get more performance for less!
I'll update this if I think of anything I left out!