Marcus' Corvair conversion, 914-C6 Options

[r3dplanet]

On to the air baffle.

The air baffle sits underneath the fan and fan housing but on top of the crankcase. Normally the baffle isn't coated with anything. In fact, I had a hell of a time getting it clean. And by clean I mean CLEAN. Old gasket fragments and gasket sealant really likes to stick. I didn't want it to rust when installation time came so I thought that I should have it zinc or cadmium plated. That would have been best. Powder coat would have been too thick and may be in an environment where the powder coat could melt. But then I thought about my plan to paint the cylinders with KG Gun-Kote because it's extremely thin, more durable than barbeque paint, extremely hard, and super heat proof. Plus, I can apply it at home. If I had a bunch of parts for this application, I certainly would have had them zinc/cad plated. But like powder coating, it's all about maximizing the minimum cost.

You can buy Gun-Kote in a rattle can from another manufacturer, but I went ahead and bought the industrial version. It's water based and the solids in the bottle take forever to mix. Even after throwing in some clean nuts and screws to work out the solids, my first attempt had lots of mucky particles due inadequate mixing. The second time around I mixed it for a half hour and finally achieved a good consistency. I also tried spraying with a Preval canister but it didn't work as well as I wanted to so I used a small touch-up HPLV gun that I picked up at Lowe's for $20. It worked perfectly.

So let's start with the cleaning process. Lots of chemicals. Lots of time with the Roxxon tool. Lots of time sanding. I *hate* sanding which is one more reason I'll never be a body guy. Those guys are some sort of wizards or something.

Almost clean:







It's amazing how much dirt still hides in the pores of the metal even after a couple of hours of cleaning. Not for long though.



Finally, it's CLEAN.




Not unlike powder coating, I like to preheat the part to 150 degrees first. While it's warming up I mix the KG Gun-Kote and run it through a fine paint sieve. It's the blackest thing I can conceive of. [Note the creepy photo again, but this one has more of a I'm-the-god-of-this-oven-and-I-shall-judge-all-that-you-do mise-en-scene to it]





Final product. I had to restart this once or twice due to the initial bad mix and then lousy spray results. The good thing is that acetone wipes it right off so that I could start all over again. It's just out of the oven after curing for an hour so it looked a little mottled still. By morning it was smooth and even.

[r3dplanet]

Good. It will be nice to be less lonely. One major word of advice that I'll address here but expand in the summary is that unless you go with the VW big bore conversion it isn't worth it. If you stick with stock Corvair pistons and cylinders you won't get any more power than a good, hopped up Type-4. But you will get more weight. BUT if you build a 150 or 180 turbo engine, then the Type-4 won't even touch it without a serious dollar investment. It might be a little cheaper depending on where you find your parts and deals. So far I'm in $2800 and all of the parts have been bought. But I still have $1500 worth of machine work to pay for. note also that I'm cutting zero corners and buying the very best parts available. From that perspective it would be very hard to beat this conversion on a bang-for-the-buck point of view. In retrospect, the best possible way to do this, other than the turbo engine, is to find the lowest cost 140 engine that's already in excellent shape and then do the big-bore conversion. You'd be bucks ahead.

Here's a quickie comparison:

Stock 140 Corvair Engine <-> Heavy, only really 110 horsepower. Cheap though. Can rebuild the whole engine for $2000.

Rebuild 140 + 3.1 or 3.0 big bore. This is what I'm doing. More expensive ending up at $4300. Expecting somewhere between 150-180 hp. Less expensive than building up a hot Type-4 1911 or 2056, but not by much. Bolt in conversion. No need to cut up a perfectly good 914 body. Can nickle and dime my way through it. Rebuilding means I'm intimately knowledgeable about my engine and I can really spend time doing things that are too expensive and time wasting for a production machine shop to do - like polishing the case and painting the innards with Glyptal paint, exotic coatings, cryogenic treatment of iron parts, etc.

Corvair 150-180 Turbo. Actual HP numbers apply. But you'll want to rig up an external oil cooler like the water cooled engine conversion folks do. Engines can be found and bought and rebuilt. Sometimes you can just buy a good one outright if it came from a reverse rotation rebuild already. Lots of aftermarket turbo, carburetor, and intake options. The Corvair was the very first production turbocharged car, so hopefully you enjoy retro turbo lag also unless you install a modern turbo. Also, I'm not sure a 901 5-speed has the best ratios for said lag. But maybe. I wish someone like McMark (or you!) would do up a turbo Corvair 914 so we can find out.

All options: say goodbye to valve racket and adjustment. Bleah.

I am watching with a keen eye as I'm seriously considdering the corvair as the power plant for my Q2 homebuilt.-G

[rsrguy3]

Well the Q2 is a rutan canard aircraft that was originally built around a continental 0-200 100horse a /c powerplant. I think the weights are comparable. Others are using the corvair successfully in a /c. An injected Turbo would be very interesting in this AP.

[r3dplanet]

Fantastic. There are scores of aircraft with Corvair engines on the Internet. I read through them and think that perhaps I should get into aircraft one day, but then I think of that magical day back in 1998 when my parachute malfunctioned. My bones still hurt a little. So I'll stick with the far less safe automotive option. If I were doing an Corvair powered aircraft I don't know if I would go with the turbo or just go nuts with multipoint fuel injection. That turbo has to guzzle some fuel. Still, you're obviously a million times more knowledgeable than I so I'd love to hear your thoughts.

Well the Q2 is a rutan canard aircraft that was originally built around a continental 0-200 100horse a /c powerplant. I think the weights are comparable. Others are using the corvair successfully in a /c. An injected Turbo would be very interesting in this AP.

[rsrguy3]

I wouldn't go that far. Your hands on right now, and I'm laid up in bed with a back injury. My knowledge is based only on a little bit of personal experience and a lot of research. I am a huge fan of Mega Squirt and itb's, your motor would look and sound insane with high butterfly stacks surrounding that fan shroud! I wouldn't even mess with a Turbo on this AP though, go with a healthy cam optimized for injection, stout compression and start learning about MS.-Guy
Oh, when I was younger I got to see an original Yanko stinger, it was on the corsa body, man was it a serious piece of work. Nader really screwed America on that deal.

[barefoot]

(*) Fun Fact: The Daniel Fahrenheit temperature scale is based on the lowest temperature he could make in the lab with alcohol and brine, or what he determined would be zero degrees. The high point was based on the human body which he scaled to 100 degrees. By repeatedly poking his extremely patient wife, Wilma, with thermometers he achieved his points and scale. But it turns out that she often had poor health with fevers so it's a bit high. Corrected for non-fever, it's 98.6 degrees. I wish so badly that we used the Metric / Centigrade system in the States, but frankly the goofy system we have is a LOT funnier.
[/quote]

Well at least we don't use British units like stones or fortnights or imperial gallons
I once asked a Rolls Royce engineer why they use imperial gallons/ time unit for gas turbine fuel flow when they could have more precisely used stones per fortnight.
Barefoot

[Dr Evil]

I really want to build another engine. If anyone is interested, I would be happy to do one for them. It helps that I have found NOT to use the roller rockers from that one supplier mentioned in my other post. Complete shite.

Also, I would be happy to share my CIS intake design. My welding is not great, so you might want to get Mark or Scotty to weld it up, but I can supply the plans.

[r3dplanet]

I'm all hot over your CIS system. I would LOVE to get your plans to build one up for myself but I have no real fabrication ability and I sold my welding gear off last year.

Coming up soon are my modifications to a set of Ford roller tip rockers. You totally saved me from getting those cheap ass roller rockers from CS, and to go with the full Clark's setup (rockers, girdles, extra deep valve covers, studs) is $1000. I'm not sure I want to spend that on a smidge of extra efficiency. So I'm splitting the difference and going with the Ford roller tip rockers. I'm working on them now and will post the modifications.

[Dr Evil]

I didnt post here, bit might as well put this information here as well, that after I did a closer inspection all but one of the roller rockers from CS were about to fail and not centered. I checked my geometry while engine on stand, and rechecked, and verified that all the stuff was moving the way it was. I got the wrong parts from him when he first tried to help....check my thread for those details. The owner is not a bad person, per se, he just sells a shitty product. I have since gone back to stock with lash caps due to the valve stem faces getting messed up by the roller rockers failing.

[gandalf_025]

I don't know if the reverse rotation cam set ups still use aluminum gears,
but if they do, be sure to pin the gears to the cam..
The stock key setup can fail.

As evidenced by this picture.



This gear was in a 1965 Turbo Coupe that the owner couldn't get to run
right. He started taking it apart but lost interest.
Look at the size of the keyway. Can't imagine what the timing was like..

This is just a FWIW

[r3dplanet]

Hey, thanks for chiming in.

My machinist installed my cam gear, which I picked up from Clark's OTTO catalog. It's a modified design from the original. It's made from aluminum and uses a fail-safe steel retainer ring to keep the gear fixed. You have to heat up the gear and freeze the cam, install the gear on the cam, and then lay over the steel retainer ring into a groove on the back of gear with a press and then let it sit there until the temperatures equalizes. I think that the stock cam gears needed to be pinned for exactly the damage you mention. But I don't think you need to do this for the fail-safe style.

Thanks for keeping me in check! I do so appreciate peer review.

I don't know if the reverse rotation cam set ups still use aluminum gears,
but if they do, be sure to pin the gears to the cam..
The stock key setup can fail.

As evidenced by this picture.

This gear was in a 1965 Turbo Coupe that the owner couldn't get to run
right. He started taking it apart but lost interest.
Look at the size of the keyway. Can't imagine what the timing was like..

This is just a FWIW

[r3dplanet]

Here you go. This shows the newer style cam gear and the steel retaining ring.

[gandalf_025]

Looks like a much better way to attach the gear.

I just checked out the Clarks web site and they
certainly don't give it away though.
I used to drive a Corvair because they were cheaper
to keep running than my 6..
They were great winter cars too.

First time I bought parts from Clarks, he was selling
parts out of his house.

[r3dplanet]

So just making a quick report here. I received the rotating assembly back from the machinist after having everything balanced.

The heads, engine case, and connecting rods are off to the specialty machinist in SoCal for the 3.0 conversion. I've decided to go with 92mm thick wall pistons and cylinders (standard 66-74mm stroke) from AA as opposed to 94mm cylinders. This will drop displacement from 3.1 to 3.0 liters, but I could care less about that since this will leave significantly more meat on the heads and produce a longer-lasting engine in theory.

I've also decided to skip the roller rockers and use small block Ford roller-tip rockers instead. It isn't just what happened to Dr. Evil's rollers bought from a lousy vendor, but I've spoken to several Corvair specialty machinists who say that even the high quality roller rockers like to burn through the needle bearings. I'm not down with that. So I'm splitting the difference and going with roller-tip rockers instead. In truth even the bone-stock rockers are perfectly fine. I'll detail the modifications when they return.

One interesting note: you can do this same engine modification and use VW stroker (88mm) cylinders for even more displacement. If you do this, you can machine VW Rabbit or Honda B16A connecting rods. You know, if you wanted to go totally nuts.

The last note is that my machinist had a hell of time machining down the conversion flywheel from Starr Cooke. Cooke doesn't actually do the modification work, he just sells them. But the one I bought sucked. The step was all over the place. Both the top and bottom surfaces were horribly uneven. My machinist called up Cooke to find out what's what but he just played dumb. He was able to surface them down to an acceptable level, but it took him nine hours to do it. In his words, "Marcus, if this was anyone but you I would have thrown this thing in the trash instead of spending all day on it." Yikes. Words of warning.

I'm expecting the turnaround to take quite a number of months, so it might be a while until the next update.

-marcus

[vw505]

How is the work going, I have read this post about three times. I am looking for a core motor now.

[Dr Evil]

Ya howsit goin? I hope your health is holding up (IMG:style_emoticons/default/smile.gif)

[r3dplanet]

Peeps,

Apologies. I'm only a month past my stem cell / bone marrow transplant. I'll be down for several more months. Right now I'm spending my time in bed staying unconscious and enjoying a liquid diet in the brief moments that I'm awake. I have the strangest dreams.

Having said that, the project is still go. I'll drop in more as I'm able.

Your pal,
Marcus

[Mike Bellis]

Peeps,

Apologies. I'm only a month past my stem cell / bone marrow transplant. I'll be down for several more months. Right now I'm spending my time in bed staying unconscious and enjoying a liquid diet in the brief moments that I'm awake. I have the strangest dreams.

Having said that, the project is still go. I'll drop in more as I'm able.

Your pal,
Marcus

Take care of yourself. We can wait. (IMG:style_emoticons/default/smile.gif)

[ben*james]

Heel up fast Marcus, you've got work to do!

[r3dplanet]

The following text is personal. Feel free to skip it and spend your time here instead: http://www.rubiksolve.com

***

I've read that our brains make decisions by utilizing use of only a tiny fraction of our rational frontal lobe parts of the brain, and most of decision making is emotional in nature due to the way we've evolved over time. Add to that that this happens at a purely unconscious level. By the the time you think you've decided on something as good thinking, you're really only rationalizing what your emotional brain has already decided for you several moments prior. It's why diets don't work. Or why we choose mates based on sexual desire. Or why anyone ever bought a Snickers bar. Or an old Porsche.

Because I've been in the dumps for many months now (although I'm up and about and healing rapidly) I've had nothing but time to really reconsider my life, and in what I think is a surprisingly rational way. And it basically sucks. I have bad habits. I spend way more than my means on my many projects, automotive or otherwise. I'm self-employed which is a fancy way of saying that I'll never be able to retire from a job that I increasingly despise. And my recent medical adventures have left me bankrupt, again. As much as possible, I really want my recovered self to do things smarter. Like finding a better job where I can ask for a good pension and six months off at a time for things like heavy chemo and transplants. Maybe ditch my car projects and use the money to buy a dependable car like a Golf TDI or a Ford Fiesta. Eat cabbage soup seven days a week to maintain a reasonable body weight. Buying loafers. Things like this.

During the past ten years I've thought that I was going to die at any moment, so spending ludicrous amounts of money on a 914 or Barracuda or tools or appliances or organic vegetables seemed reasonable. But now that I'm in serious danger of having a future, my thoughts have changed. As I lay on the couch now eating this container of yogurt trying to think about a smarter future I wonder about the wisdom of 914 projects.

My uphill battle of 914 ownership now includes the following:

- I've spent way, way more on this 914 fixer-upper than just buying a good one. The same holds true for my 'Cuda.
- The car has more passenger side long rust that I ever knew, discovered after the car was stripped and painted
- The Corvair machinist has gone missing - along with the engine parts
- I haven't worked in six months and I need to cough up at least $25,000 for more medical bills. Doable over time, but depressing.
- Thinking that a career in crime is an inevitable outcome of my life's path to date, but can't figure out how to profit from third-party arson

I haven't made any major decisions just yet. I'll hold on to the 914 for now and see if my mind changes over the coming months. But it's hard to escape the (apparently rational) thought that maybe this isn't the right path for me any more. Maybe it makes more sense to purge, burn, recycle, or sell all of my 914 stuff and take up a cheap hobby, like repeatedly solving my Rubik's cube.

Thoughts? Input is always welcome.

-marcus