I'm debating ordering the first Gen 5th bearing.  Is anyone or do you know of anyone flying with a 5th bearing on a standard non-nitrided crankshaft?  Not really about saving money as much as the nitriding and machining of the stock crank adds up to the point that a new crankshaft  realistically starts looking like an option.  I keep hovering over my online shopping cart just haven't jumped as of yet.



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Good morning. Trying to clarify your question as to me there are two parts. 

1) You are debating on ordering a 5th bearing: To me this is NOT an "option" but the basic building blocks of the Corvair engine as it has been found that crankshafts have broken (in flight) due to the loads put on them. The 5th bearing was added as awareness grew about the stress loads put on the crankshaft. It is "required" more or less.

2) Is anyone using a 5th bearing on a standard "non-nitrided" crankshaft: Good question. That I am unsure of. But I am agreeing with you if you are within hundreds of dollars or even a thousand, I also would seriously consider simply buying new. And new I mean I would probably go for Dan's new stroker crank and get the extra torque and horsepower to boot.

I am curious about the second part.  The first part is just debating purchasing the "Gen 1 Retrofit bearing" which seems could be used with a standard unmodified crankshaft as it is simply bolted on and aligned to the motor. 

Have you been reading flycorvair.net?  Built as recommended not only will save your ass,  your insurance provider will likely pay claims, (liability, hull coverage), if needed.  If you are saving money on basics so you can get the latest gee whiz panel consider changing hobbies.  This stuff can kill you.

No glass panels for me. I'm just looking at the available options.  Seems like the stock reworked crankshaft will easily be in the $2000 range (with the 5th bearing).  I don't like risk and I don't gamble,  also don't expect Lycoming crankshaft strength from the corvair.  Just curious if others have added the bearing to a stock crank without the nitriding process.  Until very recently I was considering nothing less than the Azelea IFB. I like the design very much.

Hi Charles,  I highly recommend the Azalea Aviation products.  Better engineering to be frank and excellent performance.  All engine parts, blocks or completed engines and all components for firewall forward packages at one shop.  I purchased and assembled the 129 HO model and test ran at Azalea then purchased the entire FWF deal.  Turned out beautifully.

John Minatelli

Our story is... 3 litre case was line bored, stock crank was absolutely nitrided and trued with 5th bearing installed.

I've decided to do the Retrofit 5th bearing on my reworked crankshaft. Getting ready to send my crankshaft off for nitriding and stress relieving.  


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