912 Big Bore

[BigJohn]

Just over 40hrs on the Zipper 1622, and all has been Great, We opened it up to check the internals and no issues all is looking great inside, Slight Lead Bromine powdering on the piston tops but I use Declin in the fuel and it is doing as designed on the Lead. Am leaving late June for a trip into the back country of Ore, Wa, Id, Mt and will be taking one of the Grandsons for part of it and thought it would be a good idea to open things up and get a close look inside, I truly believe the Zipper conversion is stronger built than stock and you can't beat the improved performance for the $. Hope to see some of you on the trip, You can get a close look at the Zipper.

[SkySteve]

Big John,
Sounds like a good trip. Looking forward to seeing you and the engine in Garden Valley, ID. My wife, Kris will be with me.

[BigJohn]

Big John,
Sounds like a good trip. Looking forward to seeing you and the engine in Garden Valley, ID. My wife, Kris will be with me.

Steve

We will be staying at Johnson Creek, hope to drop in to GV to see everyone, will be hitting some of our favorite breakfast spots, Sulfer creek, Flying B, Dixie Town, Maybe we could plan a meet up at one of them. Should arrive JC on June 27th.

[KitfoxJ]

Check this out Flyers
http://vimeo.com/m/97017752
Hal in white Rans closest with 1484 ZIPPER 11:1 vs Rans same HP Turboed.

[BigJohn]

Just over 40hrs on the Zipper 1622, and all has been Great, We opened it up to check the internals and no issues all is looking great inside, Slight Lead Bromine powdering on the piston tops but I use Declin in the fuel and it is doing as designed on the Lead. Am leaving late June for a trip into the back country of Ore, Wa, Id, Mt and will be taking one of the Grandsons for part of it and thought it would be a good idea to open things up and get a close look inside, I truly believe the Zipper conversion is stronger built than stock and you can't beat the improved performance for the $. Hope to see some of you on the trip, You can get a close look at the Zipper.

Sorry no Prop testing yet, We did modify the Exhaust to allow the larger bore to breath better, Saw an uncrease in RPM response,Much quicker and an increase of approx 70 RPM in climb out. We also moved the needle jet clips down to the fourth setting thus raising the needle, This improved the EGT temps once we pulled back to cruise from previous cruise flights. Heading to the NW in just over a week, Hope to run into some of you on the trip.

[mr bill]

What kind of exhaust mod?

[BigJohn]

What kind of exhaust mod?

Opened up the stock muffler, removed the baffling then added a second exhaust down pipe on the opposite end thus doubling the exhaust exit and reduced the back pressure in the muffler.

[HighWing]

Hal and some guys stopped by Saturday. Hal brought some of the parts used for the various Zipper conversion and they were really impressive. I took some photos which are attached. I neglected to take photos of the pistons, but being billet machined rather than cast, they were lighter than the stock pistons and looked every bit as good as the cylinders. Hal brought a scale and all versions of the Zipper modification were slightly lighter than the stock parts so installation would have only a very slight effect on weight and balance.

Hal had the high HP version on his Rans S-7 and he and another pilot did some take off demonstrations with it. It actually drew a crowd with people wanting to know what engine he had in it.

[Av8r3400]

Yeah, Baby!

A Kitfox with DRAG PIPES!

[WWhunter]

Highwing,
Are those cylinders for the 1622 or the 1484? I am about to order a set for the 105 HP kit.
I have been having a heck of a time trying to decide whether to go 115 HP or 105 HP. Flying mostly in Mn I have been burning 91 octane non-ethanol but the chance of flying a cross country is highly possible and being able to use the lower octane mogas with ethanol is inviting. Having traveled a lot (by car) I realized that high octane is not as easy to get as the regular so am thinking I should just get the 105HP kit. Also the added expense of having to change to a high-torque starter and replacing my clutch (older 1996 model engine) is another factor that wieghs on my mind. More money for gas.
Actually the plane currently performs great but I am not happy with the oil useage. Engine has the Extra-performance high compression pistons and I have been told by a couple of people this is a typical problem. Having to remove/replace spark plugs every few hours gets real old!