Looks like it is Corvair power for my Vari-EZE

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dwalker

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I have just about given up on finding an 0-200, but sourcing a Corvair core was as easy as driving an hour, handing over cash money, and driving home. I have spoken with both William Wynne and Bill Clapp and read both thier works on the Corvair as a flight engine. At this moment I am tipping heavily towards using Bill's 5th bearing and stroker crank to come out with a 3.0 liter-ish motor.
I am curious about the engine mount, and if anyone has done this setup before I would love to see some pictures!
One thing I know I will have to do is make the move from the NACA duct/updraft cooling to downdraft cooling via upper cowl mounted scoops.
I plan to use EFI and Bill has me very nearly talked into going turbo!

I will start the teardown process this coming week and then get ready to start sending bits and pieces all over for the needed machine work, cryo-treating, etc. Obviously this will be a "process" and there are lead times that are likely to lengthen rather than shorten, but I *hope* to have the engine assembled and running on a test rig by late fall.
 

patrickrio

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You may need to stick that engine REALLY close to the firewall to hit CG requirements. I think the all up weight is about 50lbs heavier, or maybe even 60.

The Vari-Eze doesn't like heavier engines very much as I recall.
 

Vigilant1

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You may need to stick that engine REALLY close to the firewall to hit CG requirements. I think the all up weight is about 50lbs heavier, or maybe even 60.

The Vari-Eze doesn't like heavier engines very much as I recall.
Apples to apples (both engines with carb, starter, alternator, plugs, etc) an O-200 will be much closer to the weight of a flying Corvair. Probably within 20 lbs. And the Corvair can be snugged up closer to the firewall without causing a big maintenance headache.
 

Daleandee

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I highly recommend a well built Corvair conversion ... but I may be a little biased! ;)

My 3.0 Corvair (the WW version) weighed 218 lbs. if memory serves me correctly, which is a few pounds lighter than an O-200.

FWIW ... Dan Weseman (SPA) has an even lighter version with his stroker crank that makes 125 horses!
 

dwalker

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You may need to stick that engine REALLY close to the firewall to hit CG requirements. I think the all up weight is about 50lbs heavier, or maybe even 60.

The Vari-Eze doesn't like heavier engines very much as I recall.
The standard Corvair motor ready to fly weighs within a lb of an O200 ready to fly. A 3litre with the VW cylinders and larger bore will weigh 5-7lbs less than an O200.

That's also assuming you use the heavy carb setup (I'm not, going EFI) and are using the stock cast exhaust manifolds I'm making stainless tube manifolds because I do not even have stock cast iron manifolds.

But even if I were going to not use the lighter configuration OR Bill talks me into the turbo, which will add 15-20ish lbs and it was a touch heavier it would be OK, as I'm also going to the "long nose" which allows me to run the battery(ies) further forward, similar as running an O360 in a Long. I do not currently have a cowl, but the one built for the Corvair will be in carbon fibre and should save a significant amount of weight at the back of the plane.
 

dwalker

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I highly recommend a well built Corvair conversion ... but I may be a little biased! ;)

My 3.0 Corvair (the WW version) weighed 218 lbs. if memory serves me correctly, which is a few pounds lighter than an O-200.

FWIW ... Dan Weseman (SPA) has an even lighter version with his stroker crank that makes 125 horses!
I was just posting the weight info lol!

I think I will get an honest 120hp out of the motor, without the turbo.
 

rv7charlie

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Or, you could move into the current century & be the 1st outside of the STOL community to install a Yamaha Genesis/Apex....

;-)
Oh, and save 40-50 lbs while adding a bunch of power.
 

dwalker

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Or, you could move into the current century & be the 1st outside of the STOL community to install a Yamaha Genesis/Apex....

;-)
Oh, and save 40-50 lbs while adding a bunch of power.
Well link me some info! Will it swing a big enough prop?
 

dwalker

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Sorry; I thought you knew about the engines. Here's a thread on this forum:
Yamaha with Sky Trax PSRU

But there are a lot of variations, flying on a lot of different a/c. Versions of the engine from 80 hp 2cyl to 4cyl from 140-160 hp and 3 cyl from 120 hp to boosted ~200 hp. The 4cyl bare engine is ~120 lbs.

Happy to supply more links, if you're serious.
I am watching a video on it now, it is interesting for sure
 

Hephaestus

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Just be aware... Yamaha definitely has a non-traditional sound... If you're not a fan of rotax scream - you really wont like yamaha.

That said with the turbo, it's not horrible. But it's definitely an excuse to save up for some fancy headsets :)
 

Vigilant1

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The sound of one of those little Yamaha gems just seems very fitting for a Vari-Eze.
 

BoKu

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Remember that the VE is a 2.5g airplane with the O-200, so try not to add anything to the non-lifting weight.
 

dwalker

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Remember that the VE is a 2.5g airplane with the O-200, so try not to add anything to the non-lifting weight.
I am on a pretty serious campaign to lighten the V-EZE. It is a big part of the reason why the airframe is being stripped to the epoxy and not simply smoothed out and repainted. Once the wings are stripped I am going to weight them to see if they were "built light" and I might build another set. I am building the replacement cowl out of carbon fiber. The flight instruments are being replaced with an EFIS that weighs much less, and the engine monitor is also a superlight display instead of a bunch of mech gauges, and uses a CAN bus rather than a bundle of wires. As well, a lot of thought/planning/attention is going into keeping the powerplant/systems on the light side. I have not done the real math yet, but my buddy thinks I will lose about 20lbs in the panel alone compared to the original panel. Some of that weight will also come from just getting rid of the 1970's era wiring harnesses and replacing all of it with new stuff.
At this point I am even debating doing the manual noce lift, speed brakes, and trim instead of the "almost as light" electrical versions.
 

Marc Zeitlin

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With downdraft instead of the NACA duct updraft cooling- exceptional. With the "per plans" NACA/updraft cooling? Marginal
While I am aware of a few Long-EZs with downdraft cooling (and a few COZY's), some of which I've worked on and inspected, I'm not aware of any Variezes with downdraft cooling. Doesn't mean there aren't any - just that I haven't seen or heard of them.

Since the downdraft cooling systems on Long-EZ's have not proven, in general, to be any better than the thousands of LE's with updraft cooling (either with the P-51 scoop or the NACA scoop), on what do you base this claim?
 

BoKu

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...once the wings are stripped I am going to weight them...
Wing weight, especially that which is distributed by area, by definition does not contribute to non-lifting weight. Same for the foreplane. Worry more about the fuselage and what goes into it.
 

dwalker

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While I am aware of a few Long-EZs with downdraft cooling (and a few COZY's), some of which I've worked on and inspected, I'm not aware of any Variezes with downdraft cooling. Doesn't mean there aren't any - just that I haven't seen or heard of them.

Since the downdraft cooling systems on Long-EZ's have not proven, in general, to be any better than the thousands of LE's with updraft cooling (either with the P-51 scoop or the NACA scoop), on what do you base this claim?
I was basing it on a possibly flawed memory of having read about a builder who had done both, and downdraft proved out to be markedly better. It made sense to me and I accepted the information as accurate. One concern I have is routing the air up through the exhaust vs down from the top. The spacing of the 6 cylinders being tighter than the 4cyl engines seems like it will make updraft baffling a much tougher challenge.
But since I am aware of who you are and read a lot of the things you have written, I'll admit to having not a lot to back that up and am perfectly willing to go back and do more research/ listen to others.
I have considered the P51 scoop, I still feel like I'll end up at downdraft.
I'll also admit to overthinking the issue, as the Corvair has proven in other platforms to have no issues cooling.
 

dwalker

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Wing weight, especially that which is distributed by area, by definition does not contribute to non-lifting weight. Same for the foreplane. Worry more about the fuselage and what goes into it.
Wing weight is still a part of the airframe weight and I would prefer that weight is on the lighter side than on the heavy side. I get the feeling you are roundabout referring to the powerplznt, which has proven to be not just "the save as" but in the chosen format to be lighter than the "typical" 0200.
 
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