Mike T. said: This is extremely distressing if it ultimately collapses. I just took > delivery of a stock VW engine that seems to be all there and has a few > accessories (including some by Great Plains). But I want to add 1835 jugs > and a Force One prop hub, and as far as I know at least the latter is made > by GPASC and nobody else.
Sounds like you've got some decision making to do. Like Mark said, if going to 1835, why not go to 2180 cylinders & shims and a stroker crank? Of course, you'll need to do some slight case milling to fit the longer crank throw. Since it's a GP engine (or partly so?), it surely doesn't have a cast crank in it so you've got a good crank as is, but it's a mystery why it's not already drilled for the Force 1 hub. You've got a mystery engine. If it DOES have a cast crank . . . boat anchor. Mark said, "If you've ever seen a 4340 Scat crank (which is the basis for the GPASC, and maybe the Revmaster), the fillet radii are very nice, as is the workmanship. VWs broke a lot of cranks in the early days, and the Revmaster (who was probably first to do it) and GPASC hubs, paired with very robust cranks, pretty much put an end to it." VW's of both the Revmaster, Rex Taylor and GPASC models broke a lot of cranks before they learned to use forged cranks. I think Steve told me once that Type 1 VW's from Germany always had forged cranks . . . so if my memory isn't playing tricks, I don't know where all the cast cranks came from. Maybe licensed VW engine builders like in Brazil? My Force One Hub has never given me any trouble on my GP 2180 and you'd think by now the seal would be worn out and I'd get a little leakage . . . but nope. I've never taken the hub off so maybe that's the reason the threaded screw backs out sometimes with some people. Wouldn't some thread locker fix this for those to whom it might happen? I suggest this in complete ignorance having never had the problem. ******************************** I wish the best for whoever winds up owning GPASC. When Steve and Linda built it there was always somebody at the other end of the phone to get something sent, often the same day. And they had everything! I hope whoever the new owners turn out to be take the business as seriously as Steve & Linda did. Lots of history and lots of support for our kinds of planes disappeared when they left the scene and they are missed. Time and technology marches on and for someone starting fresh, I'd sure take a look at the Revmaster R-2300. The thing about it that I admire so much is that the power, both for takeoff and cruise, is produced around 3000 RPM. At faster RPM's where engines like mine produce their rated horsepower, the engine has to be run at 3400 - a ridiculous number considering all the heat produced through internal friction at that RPM.. Aerovee (POC) even rates theirs at 3600 if I'm not mistaken just so they can say their engine produces 80 HP. Cheap trick for a cheap product. The GP2180 is rated at 76 HP at 3400. The R-2300 produces 80 horsepower at the ideal RPM of 3900 and with that big Revmaster oil cooler, heat - the VW killer - seems fully tamed with this new Revmaster design. Winter flying would probably require blocking off the oil cooler. The two things I'd change about the R-2300. I'd put roller tappets on the rocker arms (or swivel feet) - (I can't believe they haven't done that already! They use them on their dragsters using the same engine pulling 640 HP!), and I'd get rid of that Rev-Flo and put an Ellison on it. Since it has dual coils for ignition and with a dead battery you can't hand prop it, one of these new very small lithium car starters would be an easy back-up to carry. The R-2300 costs about 9K brand new which is about what one can properly build a Corvair for so the R-2300 is another very good option I thought I'd remind netters about. And . . . would someone explain to me why the higher-end Rotax engines are so expensive? I wouldn't have one at any price, but what seems like blatent greed puzzles me. They're half water/half air cooled, surrender and waste power by channelling it through a reduction gear, are finnicky in various ways and have a stack of AD's six inches high and sound like a weed whacker. They're a proven engine so I'm not contending they aren't a decent engine but considering the millions of them they've produced, both for SLA's and military drone applications, their development costs are long since amortized. Just charging what the market will bear I guess. Mike KSEE ____________________________________________________________ Oncologists Freak Out Over True Cause of Cancer pro.healthresponses.org http://thirdpartyoffers.juno.com/TGL3141/5b919d5e5ab811d5e4bb6st01vuc _______________________________________________ Search the KRnet Archives at https://www.mail-archive.com/krnet@list.krnet.org/. Please see LIST RULES and KRnet info at http://www.krnet.org/info.html. see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change options. To UNsubscribe from KRnet, send a message to krnet-le...@list.krnet.org
