VW 88mm pistons & cylinders on a Corvair

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ekimneirbo

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Probably the biggest hangup with aero engines is the cost of a replacement crankshaft. I know that the Corvairs are cheap to build with the stock cranks but when someone steps up to a
billet stroker, the cost still goes up quite a bit...and cubic inches are still limited to less than the aero engines. What I would love to see is an aircooled opposed engine similar to a Corvair,
but designed around something like a smallblock Chevy (one piece seal) or an LS Chevy crankshaft. If billet engine cases could be made to hold the Chevy crankshaft and have Corvair or
VW cylinders that bolt on....maybe use Chevy camshaft cores. This would of course allow the use of 8 cylinders with subsequent displacement increase. The idea is that instead of putting a
lot of money into buying a forged 6 cylinder crankshaft, the initial investment would be in the engine cases.....then reasonably cheap and already available items like bearings, crankshafts,
camshafts would offset the initial cost of the engine cases and give the Lycosarus some real competition displacement wise. Maybe some raised areas at the cylinder base to accomodate
longer cylinder liners and then even a 4 inch crank could be used (maybe). They make taller deck heights on automotive blocks, so why not aero engines. Bottom line is that if someone
bought the engine cases, they could assemble a lot of different combinations displacement wise and if top overhauls are needed, they would be a lot cheaper than aero engines.

Well, it's good to dream............
 

Bill Clapp

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Our new stroker Forged corvair cranks are around the 1500 mark.....very reasonable for a beautiful crank....
 

Bill Clapp

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Our stroker crank has the hub installed just like it is on the standard crank...The hus (with gear) is heated, the crank chilled, and then pressed onto the crank. It is a very tight interference fit - over 40 tons of pressure to move it. It is really a one piece crank once we are finished...no safety shafts or bolts needed. It also allows the crank to be very true and robust. I dont think we can machine the helical gear onto a single forging...same reason why GM went the way they did. Plus this method brings the cost down...
 

Bill Clapp

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I have a video on my website under the engine build area that shows the crankshaft. The Stroker engine is our 120 HP version that brings the displacement to 3.1L No mods to the case or heads. azaleaaviation.com - videos on right side
 

ekimneirbo

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I have a video on my website under the engine build area that shows the crankshaft. The Stroker engine is our 120 HP version that brings the displacement to 3.1L No mods to the case or heads. azaleaaviation.com - videos on right side
Did the EAA in Azaleaaviation just happen that way, or does the AZAL have some meaning?
 

Bill Clapp

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WOW - you are the first to see that....

It really is just AZALEA (the flower) Aviation. Our town, Valdosta, is the Azalea City... the EAA is a nice by-product of it all. Funny because we are contimplating moving our business to a new location at the Thomasville Airport..the City of Roses, and our new 16,000 sq'ft facility would be next to "Flowers Aviation"......business in blooming.
 

don january

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Hey Don - sometimes my thoughts as well...my first engine const me less than 1800.00 and I flew over 180 hours before modifying...it did have forged pistons but the rest was pretty basic. No reason you can't fly on a simple engine...none at all. However as a business I have to reach different goals concerning standardization and reliability. I think I still have one of Bernie Pietenpols prop hubs around here....he just bolted it to the crank end with the flywheel bolts - and bolted a prop on! used the two carb, fan and everything...it worked...not pretty but worked. (has to a pain to change the belt in flight thought) :)
Bill what get's me is 1800.00 for a basic build and thats about what I have in mine, but then I look at the price of your's and WW engine and WOW there sure is a launch in the price. Does the 5th bearing and fancy crank and labor run up too 7 or 8 thousand? I have no doubt that both products are first rate, and a fella needs to make a buck, and my personal view of you is I think its great you dont try and sell a manual and not keep a past buyer in the dark about upgrades on the engine, unless of course you follow the other's web sight and by then the builder is already finished with their engine and has to tear down to modify. Then the 18 hundred goes up to around ??? I think you can read between the lines and see what pev's me! Heck all I want is a reliable 70 -80 hp engine that does'nt cost more then 3500.00 ( dreaming I guess) VW parts.jpg
 

Bill Clapp

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- its not that hard to do...here is the difference. If you prep your own case, (no 5th bearing) and use a stock nitrided crank (they are out there) simple aluminum prop hub, your own head work - and so on - it is easy to do yours for less than 2500. If you want all the upgrades, plus pay for someone to do all the work, plus overhead, insurance, R&D, and so on...then it is easy to see the 10,000.00 mark. However, you get a quality build with some great stuff. It all come to how much of yourself you put into it. Our kit engine is going to run about 7500 (compared to 6500 for a VW kit engine) so the prices arent bad at all. Then compare to cost of Rotax or Jabiru of 25,000...we start looking good. Then overhaul cost of a dollar per hour.....looking better.
Keep in mind that I also have years of experience, a well equiped shop and lots of stuff around here to build from. However I have paid for it all over the years in learning and growing.
An inexpensive build is easy - with the right skillset. Balance your costs, risk factors and your pilotage skills. We will be working hard on having a really basic engine kit here in the future...
 

don january

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7500.00 for a well equiped Corvair 120 hp is a great deal. I would like to see the smaller 80-95-hp gobbled up and turned for around 3500.00 but in trueth, weight,size,and I guess rpm will be close to the same? A 6 cyl. VW case would be a good effort for the changing, and part
s availabity of the jug's especially if the Corvair case's becomes exhausted. Like alot of the builder's around the country I'd love to hand you a hand full of cash and start wrenching on the KR but I must think of the Taylor Mono also and it does'nt need 60 hp. So a 4 and 6 cyl. block is needed IMO. Donpawnee 2.jpg
 

don january

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We have ideas in the works for that as well.....cant be all things to all people though....
You just keep on doing what you do Bill, I'm happy with it, I just like throwing Ideas out there and I bet your way ahead of my thought's! kr-2.jpg
 

pistoncan

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We have all kinda highjacked this poor fellows thread. I don't think he ever got an answer to his questions about the small 88mm VW jugs on a corvair. I wish I knew more about it but I don't. Maybe BC sending a container load of corvair cores down under will help.
 

aviast

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Thanks for thinking of me pistoncan! ;)

I had thought about starting another thread to re-ask my question but I kinda figure that the tangents that this thread has taken answer the question in a roundabout way: no-one has experience with VW pistons and cylinders on a Corvair.

I thought I'd ask here before I ask WW about it because he's reputed to take a long time to respond to emails.

BC: I had a long phone conversation with Ian Ratcliffe the other day and we talked about his Corvair experiences and his brother Peter's efforts to make Corvair parts available. The two of them live very near to my father-in-law who is a retired Qantas engineer and my primary technical resource. I'm over there one or two weekends a month so it will be easy for me to keep in touch with the Radcliffes.
 
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