My 72 914 Corvair Conversion Rust(me)oration- Work begins on page 4, Pulled drivetrain today. Tranny swap coming soon |
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My 72 914 Corvair Conversion Rust(me)oration- Work begins on page 4, Pulled drivetrain today. Tranny swap coming soon |
JRust |
Jul 1 2013, 09:22 PM
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#21
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914 Guru Group: Members Posts: 6,309 Joined: 10-January 03 From: Corvallis Oregon Member No.: 129 Region Association: Pacific Northwest |
Okay so here is my teaser! I've always wanted a 914-6. I finally took the plunge & bought one. Most of you are probably thinking it is a v6 or some crazy thing (IMG:style_emoticons/default/idea.gif) . You've got a week to just sit there & wonder
(IMG:style_emoticons/default/thisthreadisworthlesswithoutpics.gif) .Yeah I know (IMG:style_emoticons/default/rolleyes.gif) |
r3dplanet |
Jul 2 2013, 11:09 PM
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#22
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Senior Member Group: Members Posts: 679 Joined: 3-September 05 From: Portland, Oregon Member No.: 4,741 Region Association: None |
Jamie -
The scoop on the VW P&C conversion is that while better stock replacement Corvair cylinders and Keith Black pistons are available for cheap, the VW Type-1 design is better. Better alloy, more fins, better cooling, etc. They're almost a bolt-in to the Corvair case. Almost. To make them fit the two middle of the six need to be shaved a bit and some of the stud holes need to be widened. They also need the bottom skirt material to be shaved down .300". There's an excellent video detailing the process here: https://www.youtube.com/watch?v=B1x9vccK-N4 The big bore conversion is a four step process: (1) The cheapest thing to do is to find a machinist who's familiar with the process and find some good quality, new Type-1 94mm cylinders which are quite inexpensive. Then find some 94mm KB pistons and pins. (2) Next, you have to have a machinist flycut the heads to accept the larger diameter cylinders. That's a good time to make sure that your heads have been "staked" and modernized to solved the valve drop issue notorious to the early Corvair engines, but easily solved for decades now with the proper procedures. (3) The case needs to have the cylinder bores expanded slightly to accept the new cylinders. (4) You'll probably have to grind a little off each connecting rod and then re-balance them. When the case hemispheres are bolted up initially, you can examine the rotating assembly and see where this needs to be done and do it yourself. Or have your machinist do it. Now, you do have options. You can buy the heads and cylinders all ready to go from a well respected guy on Ebay who sells the entire heads with a new valve job and modifications ready to go for usually less than one grand. He also sells the cylinders already machined. Or you can send your stuff to him for just the machine work. See: http://www.ebay.com/itm/Corvair-140-Big-Va...c02&vxp=mtr and http://www.ebay.com/itm/Corvair-94mm-VW-ba...f44&vxp=mtr * OR * You could do what I planned to do and enlist another respected outfit, American-Pi, and pay $1575 for them to supply you with new cylinders, pistons, and rings and then do all the machining you need in one stop shopping. http://www.american-pi.com/corvair/corvhome.html You send them your heads, case, and rods and they do the rest. The Corvair guys have reports of glad tidings and positive reviews for their work. Shipping is a touch expensive, but it's not all that bad. They send you basically everything ready to assemble yourself, assuming that you already have a reverse rotation cam, gear, and distributor drive gear. And you do. I think that this would really be the way to go for most people, including myself. The good news is that the heads you need to use are the heads you already have, not the early ones. So you're ideally poised for the conversion. What all this gets you is power and reliability. The VW pistons and cylinders are a way better design, and makes the engine run much cooler and greatly prolongs its life. And of course it doubles your HP. So even if you were doing just a rebuild of a standard Corvair engine this would make all kinds of sense. Since you already have excellent working cores, a good reverse-rotation engine, and a good fuel system, you basically spend $1600 and a weekend and you're off to the races. I like to remember that at the end of the day GM basically wanted their own version of a Karmann Ghia. A bigger car but still clearly a 1950s body style with a more powerful air cooled rear engine and a ton more leg room. They prototyped the Corvair with a VW engine and then transferred the design to a six cylinder to haul around a heaver car. So there's a goofy kind of circular logic with this whole process. At least in mind it does. But I'm a crazy person so who knows where the reality is focused. Did you find the engine serial number yet? It's on top of the case right up by the front belt pulley. Also, can you send a photo of your carb/intake setup? -marcus |
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