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r3dplanet
A few years back I got all excited about doing a Corvair engine conversion for my 1971 car. The project waffled. Numbers were crunched and chewed. Thought and diagrams and opinions were drawn out over long winter evenings.

One particularly rainy winter evening, I found an ad on Craigslist advertising a warehouse full of Corvair parts including engines. So my pal Rory and I drove a hundred miles into the boonies late one rainy night to what turned out to be an unmarked, geographically isolated, former slaughterhouse illuminated by a single 60 watt light bulb. No cell phone reception, no escape. We were met by a couple of toothless brothers who couldn't stop talking about Daddy. Seemingly they only did what Daddy wanted them to do. Daddy wanted them to sell the stash of Corvair parts. Daddy wanted them to steal my Toyota cargo van. Daddy needed to approve the transaction of cash for an engine. Daddy, it turned out, was long dead. The two brothers kept trying to separate Rory and I, and the creepier of the two brothers kept demanding my car keys so he could test drive my van, despite my insistence that it wasn't for sale. For the first time in a long time, I wish I had a tazer gun on me. The brothers eventually showed us exactly what I wanted - an RD code 1965 110HP engine. Fearing for our lives, Rory and I muscled the engine into the van while the brothers went to find more stuff for Daddy to sell to us, or you know, maybe a club or some rope or a ball gag or something.

I left the $100 on the bench and tore the hell out. Rory and I laughed all the way back to town, ever so pleased that we were neither killed, nor raped, nor eaten. Plus, we were one up on a Corvair engine.

So with a provenance like this, and seeing JRust's new car, Dr. Evil's project, and 914coops Nader's Nightmare all take shape I've finally decided to get serious about my own project: the VW-Porsche 914-C6.

The "C" stands for Corvair.
computers4kids
I will be looking forward to your build thread beerchug.gif loved the story of picking up the engine. What hp are you expecting to achieve? I get the idea of keeping an air cooled engine and the simplicity. These cars a lot of fun when you get in the 200+ range.
r3dplanet
Right. My goals are straightforward. Since my 914 is essentially a weekend fun car, and thanks to the Portland weather, it means that the car is only driven for a few warm months of the year for fun weekend drives. The key word there is fun. Primarily I'm after reliability, very low maintenance, silent valve train noise, and excellent power. All in that order.

To that end I'm going with the VW Type-1 94mm piston and cylinder "big bore" conversion that takes the displacement from a stock 2.7 liters to 3.1 liters. The Type-1 cylinders are much better than the stock Corvair cylinders given the better construction, cooling, and floating pin arrangement. The engine will be rebuilt as a reverse rotation "140" motor meaning that I'll ditch the 110 heads for the better 140 heads. I'll use ARP studs and bolts for the case hemispheres and connecting rods for better strength. I'm also using a hardened and nitrided crank from the turbo motor. I haven't decided on a fuel system just yet, but I know I'll start with a four-into-one intake and single carburetor which is just fine for warm weather driving. Eventually there will be an EFI system, but first things first. I'm hoping for a true brake horsepower of 130-150. I may go nuts with headers and a roller rocker assembly. I'll skip the turbo. For reasons outlined elsewhere, I just don't think that the primitive turbo with its ponderous lag is a good match for a 901 gearbox.

The plan is to build up the motor, mount it on a frame and get all of the adjustments and initial tuning before installing it in the car. Like all of my projects, this will take forever. Patience, patience.

bandjoey
That place was featured in Texas Chainsaw Massacre sawzall-smiley.gif

Ill enjoy watching the build. biggrin.gif
Steve
Could of also of been the "home" episode of the X-Files. Good thing there was two of you.
r3dplanet
For your viewing pleasure, some barfy pics of the tear down so far.

Here's part of the reverse rotation assembly. A custom 130 tooth flywheel, an engine to gearbox adapter plate, and an Otto-20 reverse rotation hot cam. Needed still are the reverse distributor gearset and alternator pulley.

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And here's the engine as-is, right from the bottom of the Black Lagoon.

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The first thing to do is to gather 25 bins from Ikea for $4.99 each to separate and label everything. Then disassembly. To start, the magnesium fan and pulley is removed, followed by the top cover.

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Under the cover is another cover, or really a very big gasket.

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Under that gasket is another gasket, which when removed reveals the slimy innards of the crank case.

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Note. Since I'm reversing the motor and mounting in "backwards" into the car, for the sake of 914 terminology I'll henceforth switch the terms "front" and "back" from what GM people would use. On the front of the engine there's a aluminum assembly that houses the oil filter, oil pressure sender, and speedo cable. Six bolts and it pops off easily.

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Then the oil cooler.

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And finally the front engine cover which is held in with seven bolts and several nuts holding the bottom plate / front engine mount.

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r3dplanet
That front engine mount plate is the bearer of mysteries and a handy place to keep an assortment of extra fasteners and probably some chewing tobacco.

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The valve covers on the later engines like mine are held on with four bolts and these elongated strips of metal to spread the load. Apparently this makes for an excellent seal.

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The head for cylinders 1-3-5 showing its glorious hydraulic rockers. The nuts that hold the rockers down thread onto special studs that double as the nuts for the lower head studs. You can see the upper head nuts and they are RUSTY. It took a few days of Kroil, swearing, and heat to remove them. But hey, they held their torque.

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The engine is missing most of the sheet metal tins, but I'll cross that bridge when I get to it. But what little there was removed easily.

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Three nuts hold the exhaust log. Once removed, it popped right off. This design uses no gasket.

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Off come the bottom head nuts.

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I ended up having to drill off the center top head nut and then use a cold chisel to split it. It's too tight in there to get a nut splitter. Underneath was one incorrect sized washer.

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The pushrods are removed and marked for the sake of developing good organizational habits.

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Then the pushrod tubes are pulled. If these are straight, I'll clean and paint them and use some new viton rings on reassembly. They're made of aluminum steel.

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r3dplanet
The head is free but before removal the carburetor mount studs need to be removed.

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There are also nifty coil springs riveted to the bottom of the head. This pushes a small tube when heated upward to deactivate the choke on the carb. Not too different from the original heat pipe mechanism on my Chrysler 273 engine. Once removed the head can come off. A very slight tap with a mallet is all that was needed.

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Off with her head!

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Yeah. She's had some wear.

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Cylinder #5 has quite a bit of bonus debris. icon8.gif Doesn't matter. These cylinders and pistons are headed straight for scrap.

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Now I need to remove the cylinders, pistons, and rods.

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aircooledtechguy
QUOTE(r3dplanet @ Jul 10 2013, 09:50 AM) *

One particularly creepy evening, I found an ad on Craigslist advertising a warehouse full of Corvair parts including engines. So my pal Rory and I drove a hundred miles into the boonies late one rainy night to what turned out to be an unmarked, geographically isolated, former slaughterhouse illuminated by a single 60 watt light bulb. No cell phone reception, no escape. We were met by a couple of toothless brothers who couldn't stop talking about Daddy. Seemingly they only did what Daddy wanted them to do. Daddy wanted them to sell the stash of Corvair parts. Daddy wanted them to steal my Toyota cargo van. Daddy needed to approve the transaction of cash for an engine. Daddy, it turned out, was long dead. The two brothers kept trying to separate Rory and I, and the creepier of the two brothers kept demanding my car keys so he could test drive my van, despite my insistence that it wasn't for sale. For the first time in a long time, I wish I had a tazer gun on me. The brothers eventually showed us exactly what I wanted - an RD code 1965 110HP engine. Fearing for our lives, Rory and I muscled the engine into the van while the brothers went to find more stuff for Daddy to sell to us, or you know, maybe a club or some rope or a ball gag or something.

I left the $100 on the bench and tore the hell out. Rory and I laughed all the way back to town, ever so pleased that we were neither killed, nor raped, nor eaten. Plus, we were one up on a Corvair engine.


Damn!! I could hear the "dueling banjos" playin' in my head as I read that one!! av-943.gif I think you are very lucky to have got out of there in the same condition as you arrived. . .

I look forward to your build!!
rick 918-S
Fun biggrin.gif
JRust
Oh man what have I done happy11.gif .Excellent Marcus! @ Corvair powered 914's within an hour of each other will be great. You are sure tearing into yours quick. I'll be watching your build as I keep my eye's open for the pistons & cylinders for mine biggrin.gif
FourBlades

Cool, its the "Hills Have Horizontal Fans" build.

Now burn those gloves and wash your hands. Twice.

And check for tracking devices.

Good luck.

John
sixnotfour
you guys should group buy 3 x 4 = 12 john barnes up in Seattle does corviar machine work..
Randal

What do you use to clean up all the metal work?

How about soda blasting, but maybe that leaves residue that could cause engine problems.

Looks like a fun project.
Dr Evil
thumb3d.gif all you need for tins are the top and the two bottom ones under the cylinders. They rest needs to be fabbed, but this is actually easy. Cant wait to see this.

Why did you want the 110? The 140 comes with a nitrided crank. Roller rockers have been a nice touch on mine. I have a 4bbl to 6 port adapter if you want to do that smile.gif
Dr Evil
Oh ya, I also have another 110 naked head if you want. Just pay shipping.
Dr Evil
You can sell those P/C to Clarks for cores. Beats scrap price, maybe smile.gif
r3dplanet
Hi there.

When the project first started, I wasn't at all interested in power. Just a silent valve train and decent power. Many Corvair folks chimed in to tell me that the 140 motor was only faster at the very top end, and that the 110 was actually faster off the line. The 110 also had better mileage. Also, there's a cool EFI kit available here:

http://www.corvair-efi.com/Injection.htm

... and it only works on the 110 heads or lower. I still think that this EFI setup is the cat's pajamas. I'm not sure what I'll eventually settle on for a fuel system but I'm sure I'll get it figured out soon.



QUOTE(Dr Evil @ Jul 12 2013, 09:11 AM) *

thumb3d.gif all you need for tins are the top and the two bottom ones under the cylinders. They rest needs to be fabbed, but this is actually easy. Cant wait to see this.

Why did you want the 110? The 140 comes with a nitrided crank. Roller rockers have been a nice touch on mine. I have a 4bbl to 6 port adapter if you want to do that smile.gif
r3dplanet
That's good thinking. I won't be re-using the 110 heads I have now since I'm planning on buying a set of rebuilt 140 heads. But it's good to know that I can send them off to someone at Clark's who might make use of them.



QUOTE(Dr Evil @ Jul 12 2013, 09:15 AM) *

Oh ya, I also have another 110 naked head if you want. Just pay shipping.

r3dplanet
I usually just bring a carload of parts to Gary, my friend and super genius machinist. He hot-tanks everything for me. Short of that, there's also a metal dipper here in town and many blasters. For small parts I run everything through my ultrasonic cleaner with Simple Green and then coat everything with Boeshield. Finally, my plan is have all of the sheet and peripheral metal blasted and then powder coated. In fact, most of the parts I'm disassembling will not be re-used on the project. Mostly I just needed a good crank, crankcase, connecting rods, pushrods, pushrod tubes, hardware, attachment pieces, etc. All easy enough to have tanked or dipped.

-m.


QUOTE(Randal @ Jul 12 2013, 08:00 AM) *

What do you use to clean up all the metal work?

How about soda blasting, but maybe that leaves residue that could cause engine problems.

Looks like a fun project.
r3dplanet
More disassembly.

Because the motor is a touch on the frozen side I couldn't remove the cylinders, rods, and pistons as a unit. Therefore the cylinders are coaxed off one at a time. Cylinders 1-3-5 are free.

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Now on the starboard side of the engine. I found that every one one of the top head stud nuts was frozen. It took two days of part-time work to torch each one repeatedly with MAP gas intermixed with drilling a 3/64" hole on either side of the nut and then splitting it with a sharp chisel. One can easily see that there's no nut where I'm torching. There was, but this is just for photographic clarity.

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The starboard heads look even worse than the port heads. I have no clue what the hell happened on the outer two chambers to make them look so lousy.

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Even more debris on the #2 cylinder.

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Finally free of the cylinders, the engine now spins quite nicely.

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Now I can finally work out the connecting rod nuts. This actually took quite some time to remove. The bottom ones are hard to reach.

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All clear.

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r3dplanet
Flipping the engine shows 19 bolts to remove the oil pan. I'll discard this item also in favor a much better aftermarket aluminum unit with cooling fins.

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And the oil pickup is revealed.

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By CAREFULLY tapping the bottom of the dipstick tube with a 16oz hammer the case is free of one more accessory.

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The oil pickup tube was really stuck. But I found that I could use a long extension and a 10mm socket to carefully drive it through the case from the outside. GM made a special tool for this job but it's completely unavailable.

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This part I've been dreading. The clutch, pressure plate, and flywheel assembly were just on the wrong side of the engine stand, and all of the bolts were super rusty. After a two day soak with Kroil, I was able to slowly draw them out.

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The clutch plate and clutch disc are free. I unbolted the bottom bolts on the engine stand and was able to drop them right out.

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And finally the flywheel is revealed. The six flywheel-to-crank bolts looked as rusty as my high school German language skills.

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I couldn't keep the rotating assembly from spinning when I tried to loosen the bolts. So I threaded one bolt into the flywheel thread and another to the case and wedged a 1/2" combination wrench in between them. With even, heavy pressure on my long socket wrench the bolts slurped right out.

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Finally just the bell housing bolts remain, but I need to prop up the crank case first. That's a job for this coming weekend. The bell housing, clutch assembly, and flywheel will also be discarded since it won't be used in the 914.

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Dr Evil
Your heads show that water and oil were allowed to accumulate in there.....common with poor storage practices dry.gif
r3dplanet
Yeah, it was pretty damp in the slaughterhouse.

QUOTE(Dr Evil @ Jul 12 2013, 11:23 PM) *

Your heads show that water and oil were allowed to accumulate in there.....common with poor storage practices dry.gif

relentless
Ah, this brings back memories. My buddy had ran my 1.7L up to around 70mh in third passing a car, and caught second gear instead of fourth. So I was looking for a "new" and more powerful motor. Back in 1980 I started with a $250 140 Corvair engine and by the time I was done I had over $3k invested. Back then, I could have had a decent Porsche six for that price. confused24.gif

You mentioned something about a stock 2.7L going to 3.1L, but as I recall the stock Corvair was 2.4L and I went .030 over on pistons to get about 2.7L. I was assisted in the engine build by "Terry to the Nth" who made me do everything perfect - or else! He even CC'd each head so we'd know exactly what the C/R was - to the drop! Keith Corp in Ashland balanced all the reciprocating parts and the engine sure was smooth. He said it would be good for 8,000 rpm.

The main problem I had with the reverse rotation engine was having the fan belt pop off a few times. Kind of a dizzy design, the belt going from horizontal to vertical and back. I tried mounting a spring from the idler pulley to the firewall but the racket from the spring was horrendous. I think I went to a slightly longer fan belt to solve the problem.

So welcome to the world of Porvairs, where we spend lots of dollars to make our cars worth-less (not worthless).

Oh yeah, I just remembered that Terry made me take the block down to the airport and have it zyglowed. They use a special dye to check the aluminum block for cracks.
Dr Evil
Why would you put a spring on the tensioner when it is held in place by bolts??? It is not dynamically adjustable.

fan belts pop off when they are on too tight. I have not had one come off, yet. I know many vair owners that have not popped belts once adjusted looser.

The engines are 2.7 from 65 on. Earlier than that they had different sizes which I dont know.
rick_cv
Just curious. What do you use for flywheel, clutch and pressure plate? I have seen a few 215mm flywheels for vw/corvair conversions but the seem to be rare and expensive.
r3dplanet
Good question. The flywheel is a custom part that's been produced by many manufacturers for decades. Crown, KEP, Otto, and others have made them. It's essentially a 130 tooth solid flywheel that has a built-in pressure plate. See photo #1 of this thread. The actual clutch disc and clutch are stock VW/Porsche parts and you can use any item you want. The 130 tooth flywheel is basically where the transition happens. The flywheel bolts to the crankshaft, and then the tooth arrangement allows for use of the stock starter. If you just swap the pinion gear in the gearbox, you would then have to use a reverse rotation VW starter or a stock Corvair starter with a small adapter. Somewhere I have the rest of the clutch pieces. When I find them I'll post pics.

Also, someone else asked about displacements on the engines. The very earliest 1960 Corvair engines were 140cid, but after 1961 a 145cid engine was made an option. With 1964 models (the great transition year) all displacements went to 164cid (2.7 liters).

-m.
Dr Evil
I got a set off of ebay; Crown adapter from engine to VW gearbox and flywheel. They are packed up for a future project. It was not that expensive, all things considered.
rick_cv
I see 127 tooth, 130 tooth and 215mm flywheels. I take it the one to use is the 130 tooth. Do you use a bug pressure plate/clutch, bus or 914? Or a special pressure plate/clutch for the conversion. Thanks for the replies fellas. I thought JRusts new project was pretty neat also and will probably never have the money to do a Porsche six conversion. Just following my curiosity.
r3dplanet
You certainly want the 130 tooth flywheel. I genuinely don't know if the clutch and pressure plate is straight VW or 914 specific. But since I want to clean up the assembly I have, I'll take it apart, get some photos, and glean any part numbers. All I can see right now is that I have an F&S pressure plate.



QUOTE(rick_cv @ Jul 15 2013, 01:55 PM) *

I see 127 tooth, 130 tooth and 215mm flywheels. I take it the one to use is the 130 tooth. Do you use a bug pressure plate/clutch, bus or 914? Or a special pressure plate/clutch for the conversion. Thanks for the replies fellas. I thought JRusts new project was pretty neat also and will probably never have the money to do a Porsche six conversion. Just following my curiosity.
r3dplanet
Okay, I have to admit that I'm a little confused but I'm sure that this challenge will be met and solved. To solve the curiosity for rick_cv, myself, and perhaps others I disassembled my crusty part.

The flywheel assembly is a sandwich made of the clutch disc, flywheel, and pressure plate. The pressure plate is bolted right to the conversion flywheel with the clutch disc kept inside. Here's a closer pic. I know these parts are rusty, but they'll be cleaned and balanced before being put into service.

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Apparently, this flywheel assembly is from Kennedy.

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The clutch disc is also F&S (which is just Sachs now, isn't it?) and measured 180mm, quite a bit smaller than the 215mm 914 clutch. Hopefully that won't be a hideous issue. But the 180mm size tells me that this is a standard VW part - not a 914 part. Clark's sells three clutch discs. A standard VW clutch, and high performance clutch, and a racing / high hp clutch. I'll probably replace this clutch disc for one of the racing ones.

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Finally, here's a pic the recesses for the flywheel bolts.

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Dr Evil
That is a bus pressure plate. Possible a bus flywheel and disk that has been converted as well.
Dr Evil
Here is Clarks catalog for the conversion flywheels.
http://www.corvair.com/user-cgi/catalog.cg...mp;page=OTTO-39
rick_cv
That is what I thought when I first saw your image- that's a bug pressure plate. Don't know if it works with a 901 trans though. Will be watching this thread to see how it comes together.

Some good tidbits-

http://www.tunacan.net/t4/tech/flywheel.htm
r3dplanet
From what I've read the adapter plates should fit any VW or 901 gearbox of the period. But I'll cross that bridge when I come to it. We're sort of getting ahead of where I want to be, so this issue will be revisited when the time comes.

QUOTE(rick_cv @ Jul 16 2013, 12:45 PM) *

That is what I thought when I first saw your image- that's a bug pressure plate. Don't know if it works with a 901 trans though. Will be watching this thread to see how it comes together.

Some good tidbits-

http://www.tunacan.net/t4/tech/flywheel.htm

r3dplanet
I've taken the past couple of evenings to do some cleanup and hit the reset button on my work area. I douched the tools with WD-40, cleaned the parts I've removed with my ultrasonic cleaner and then coated them with Boeshield, and finally bagged and tagged them. There are a large number of parts that won't be re-used for this application: flywheel, pressure plate, valve covers, bell housing, heads, cylinders, etc. It feels weird tossing that stuff aside. From an existential point of view it's really thought provoking to think that at this moment the engine does not actually exist. Instead, it's just several bins holding a bunch of constituent parts in a garage explosion. Leaving and returning. Chaos and Cosmos. Big Bangs and Brahma years. Hey, I was an academic for a long time so this is where my brain goes when I'm in the shop. Inner space. Besides, Carl Sagan is my spirit animal.

So here's the detail on the final stages of disassembly. After removing the engine from the stand and setting aside the bell housing, this lovely creature now graces my workbench. One might wonder why it looks like a robotic pin cushion. This is because the head studs are not to be removed from the case unless it's absolutely necessary. There's a test to torque them down to 30 or 40 lbs (depending on which manual you read) and see if they hold their torque. If they do, then it's smooth sailing. If not, then it's time for creative machining.

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Here's a front view for no reason.

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This part is the oil cooler adapter. I could have taken it off at any point during the disassembly, but both the 1965 Corvair Chassis Shop Manual and Bob Helt's The Classic Corvair say to leave this connected until this point. By the way, these manuals are fabulous. For dolts like myself they're really a fantastic resource. If you do a Corvair conversion yourself, be absolutely sure to get them. They're both in print.

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And .. removed.

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Now it's time to split the case. Here's a side view clearly showing the eight through-studs and corresponding nuts that hold the hemispheres together. Four on top, four sort of in the middle. Just before removing them I made sure to remove the bottom bolt that holds the oil pickup to the case.

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Having the motor on the bench sure makes this part straightforward. Using a ratchet and a long socket wrench, each comes off in turn with a little effort. No crazy stuck nuts like the ones holding the head.

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Now the big moment. A slight tap with a rubber mallet along the top edge of the inside of the case and it just pops apart. It took very little effort.

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In fact, it popped apart a little too readily. The manual says to prop the bottom of one half of the case with a 2x4 to push one side of the engine higher than the other. That way you lift the free half and leave the crank and cam in place on the other side. This is to prevent the crank and cam from just spilling out onto the floor. Just as I reached for the wood, it split right open. Whoops.

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Yeach. This crank bearing is scored all to hell. The opposite side is also. The rest of them look like they have normal wear.

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r3dplanet
Moving along with a close-up of cam wear. This doesn't matter as the cam and cam gear will be replaced.

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A glamor shot of the starboard half of the engine with the hydraulic lifters and crank bearings removed, which I'll catalog and keep for reference. Note that the Corvair engine does not use cam bearings. Instead, the cam rides only on the oil between the cam and the engine case. I might have the cam surfaces coated with Teflon before re-assembly, assuming this case checks out. Before getting that far I'll get the case hot tanked and checked for cracks with Zyglo (thanks, Relentless!). That's coming up next.

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The corresponding glamor shot of the port side of the engine. This is the end of disassembly. Next up: finding a suitcase full of money to get the rebuild parts and checking and prepping the parts I already have.



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relentless
You're making good progress Marcus. It's been 33 years since I built my Corvair engine, but bits and pieces of the process keep coming back. smile.gif

As I recall Terry (to the n'th) didn't want me to go more than .030 over on the barrels because he was concerned about the thinner metal being less able to dissipate heat and also he had me get forged pistons, and I believe Moly coated rings (?). Seems like there was a specific cross hatching on the cylinders also. Every time I'd go wild and suggest something like boring the cyls out to .060 he'd look at me and say "do you want an engine that lasts ten thousand miles or one that will last longer?"

I'll be interested in seeing what advances they have made in the last three decades and what parts you select for your build.
Dr Evil
No special cross hatch, no special rings, and you can bore out farther if you open the registers which is required when using the TI VW cylinders. Please do not put forth partial memories as gospel unless you have some backup for them as this can cause damage to peoples engines and wallets in the future.
r3dplanet
Not much happening today. I spent a good hour hashing things out with my mechanic. I also hoping to get the ball rolling with American-pi about specialty machine work for the roller rockers and 3.1 conversion. I also started a thread over at corvaircenter.com asking about engine specifics. It's lively and informative. And comes complete with a troll.

http://corvaircenter.com/phorum/read.php?1,633330

Today I cleaned the crap out of the pushrod tubes, but I still plan to soda blast them and powder coat them.

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It was super nice out this evening so I pulled out the Easy-Off and the power sprayer and hosed down the engine cases. They're going to the machine shop tomorrow. Here's the before and after shots. Remember, this is just a once-over to make it easier for the machine shop.

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rick_cv
Who are you using for a machine shop? Dan Hall's still open?
relentless
Well Marcus, Dr. Evil says I shouldn't comment or offer advice as gospel, even when I put a (?) question mark after what I recall we did when building my engine, and mention it's been over three decades since the work was done. So if you want me to no longer comment or make suggestions I will gladly abide by your decision. I make no representation as to my experience being "gospel."

Maybe you would at least let me post a picture out here how the idler pulley can be *spring mounted* since D. Evil said it couldn't be done! lol-2.gif I found it interesting that someone else also had problems with the reverse rotation belt pulley; something Terry said was probably due to the factory designing the engine to track the belt under load in the original direction.
Dr Evil
Last I saw Ray Sedman (sp) was doing the 3.1 with good street credit, but not cheap. There are a few that do the service, but search the web for references. I had mine done in Harrisburg by a very competent shop that does anything, so it is possible to have a local do it if they are smart smile.gif
Dr Evil
QUOTE(relentless @ Jul 19 2013, 05:01 PM) *

Well Marcus, Dr. Evil says I shouldn't comment or offer advice as gospel, even when I put a (?) question mark after what I recall we did when building my engine, and mention it's been over three decades since the work was done. So if you want me to no longer comment or make suggestions I will gladly abide by your decision. I make no representation as to my experience being "gospel."

Maybe you would at least let me post a picture out here how the idler pulley can be *spring mounted* since D. Evil said it couldn't be done! lol-2.gif I found it interesting that someone else also had problems with the reverse rotation belt pulley; something Terry said was probably due to the factory designing the engine to track the belt under load in the original direction.

Please do post a pic. I didnt say it couldnt be done, I asked why. The original design does not necessitate a spring and make no provision for one.

As for offering your recollections on corvair engines, you only put one (?) in one of your posts, but you have posted plenty of incorrect info. My only aim is to keep info factual and accurate, not to belittle. I do not want you to leave, just check your facts. All the stuff you are posting about may apply to early vair, but not the late model, 2.7, 110 or 140hp blocks. Having built up one far more recently than 3o years ago, and modifying it as Marcus desires plus some, and researching them, it get tiring when I have to post corrections to misinformation posted in here. The vair may have the most misunderstood of all engines with lots of BS out there. See the comment about "rubber main bearings". Yes, there was a person that both posted that they used rubber main bearings AND believed it about 10 years ago when I first started into vair engines.

Marcus, there is a guy in Santee, CA named Star Cooke who knows these engines really well. He costs money and is arrogant, but if you want something done right he is an option. I have a set of his heads converted for weber 3A carbs.
r3dplanet
I want to tell everyone that this is my favorite automotive forum. We keep it technical and rarely do threads devolve into shouting matches. That's pretty much the norm for the classic Chrysler forums I belong to. I don't even post there anymore. Even my thread over at corvair central was accosted within minutes by a single assclown. One of the things I love about 914world (and BMWMOA) is how we manage to keep it clean, providing a sandbox for whomever to sling whatever. Compared to other forums I belong this, this place is an oasis. For example, when conversions are brought up nobody starts a flamewar about who's the idiot. Any conversion - Wankel, Subaru, SBC, etc., is going to be in some minor way controversial. For my own, I think it's low stakes. One day I'll build up a race car and throw the Corvair engine into it. Short story long, I welcome both past and current experiences with those who are Corvair knowledgeable (Relentless) as well as peer review (Dr. Evil). That is the path to factual knowledge. Ultimately the 914 attracts a certain crowd, and they are efficiency-loving gearheads with panache and good attitudes. So, hooray for us.

So far I found a few surprising items in this adventure: Corvair forum "experts" bicker a great deal. There has been so much time and so much development over the years that trying to find the one right way to accomplish any specific task is immediately grounds for argument. Sorting out what's right for me has taken far more time than I had expected. For example, with rockers. There are a myriad of ways to do this and it doesn't help that GM doesn't make them anymore. So there are dozen solutions for replacement, each of which has it's own believers who think the others are stupid. I mean, seriously, rockers.

Another surprising item is there are very, very few washers as far as fasteners go. I'm used to finding lock washers everywhere I look. On this engine I've found only a few. The nuts all seem to be nuts + flange to make a ... nutwasher.

As far as machine work goes: the case prep, crank regrind/polish, balancing of rods, flywheel, etc., is all done by my friend and machinist Gary who's a super genius.

For the specialty stuff like the head, rod, and case work for the 3.1 conversion is (hopefully) going to be done by American-pi. Their work appears stellar and I think the most economical way to go.

Dr. Evil, you hit the nail about Star Cooke. I'm buying my 140 heads from him. Expensive, but absolutely rebuilt correctly by a guy with an excellent reputation and spends his days doing this exact work. It's worth the money for the piece of mind.
Dr Evil
I can not seem to stick around on other forums. This one takes what little time and attention I have and I like it and the people so much. smile.gif I have met probably 1000 of the members her all over the country and in Canada (they count, too). You have a great attitude, Marcus.

The one thing that I found good fighting over was how to bore the case. Sedman has the "actual blueprints" and bores the case where the registers where supposed to be, not based on where they are. I did not bother with this and just had them bored. My fuel systems have been the only problems as I continue to experiment.

Have you seen Mark Langford's aircraft page with his 3.1 conversion? Lots of great info there. Also, there are good threads here with links.
andys
I think it was one of the HP book series on "How to Hot Rod the Corvair" that I bought when we ran SCTA (dry lakes) out at El Mirage in the late 60's (ran a 180 Corsa in F/Supercharged). Wife recently complained about my library (catch-all) so durring my clean up, I think I threw it out. I hung on to that book for 40+ years.

Andys
JRust
QUOTE(r3dplanet @ Jul 19 2013, 03:04 PM) *

As far as machine work goes: the case prep, crank regrind/polish, balancing of rods, flywheel, etc., is all done by my friend and machinist Gary who's a super genius.

For the specialty stuff like the head, rod, and case work for the 3.1 conversion is (hopefully) going to be done by American-pi. Their work appears stellar and I think the most economical way to go.

Dr. Evil, you hit the nail about Star Cooke. I'm buying my 140 heads from him. Expensive, but absolutely rebuilt correctly by a guy with an excellent reputation and spends his days doing this exact work. It's worth the money for the piece of mind.

Man I need to pick up another motor. Maybe I can do my stuff at the same time & we can get a discount confused24.gif Much easier on a machine shop to do 2 of the same right?
r3dplanet
Wait, what? What's wrong with your motor?

I know a couple of banjo-playing brothers with a domineering dead father who could probably make you a deal. Just bring a pistol, give GPS directions to your loved ones, and bring some friends. Or it will be more like Kalifornia than Deliverance.

You bring up a point that I should probably have made earlier. I know that my project won't be inexpensive. But luckily the nature of the work is that I can pay as I go. I like that. I think that a properly stock 140 with good head work would be more than enough power for the 914. I'm going a little nuts with my engine (a) because I want to see where this goes and (b) I'm secretly trying to show that even with all of the big modifications this motor will get, it can still be done for about 1/3 of the cost of the Porsche six. I think the -6 is the coolest motor (except that POLO motor). But absurdly expensive. I'm showing an alternative. I also have a sneaking suspicion that for what I spent on my motor, it will be about the same as a souped up Type-4. Last, for what I'm spending on the monster 3.1 liter, I could have spent less than half and built up a stock 140. That's where the smart money is.

So - yes! Maybe we can double up on some machine work. We also need to develop a nice cradle for the engine.

I've already learned that if I were doing this again I wouldn't even bother with a donor motor. At the end of the day I'm only using the major pieces from the donor, and I'm sure I could have found cleaned and prepped bits for about what I spent ($100) on the motor.

As of today, here's the bucket of reusable parts:

Click to view attachment

Aside from the engine case and crankshaft, this bin includes the top cover, front cover, oil filter assembly, fan (and bearing), and pushrod tubes. Everything else is scrap.

QUOTE(JRust @ Jul 19 2013, 05:27 PM) *

QUOTE(r3dplanet @ Jul 19 2013, 03:04 PM) *

As far as machine work goes: the case prep, crank regrind/polish, balancing of rods, flywheel, etc., is all done by my friend and machinist Gary who's a super genius.

For the specialty stuff like the head, rod, and case work for the 3.1 conversion is (hopefully) going to be done by American-pi. Their work appears stellar and I think the most economical way to go.

Dr. Evil, you hit the nail about Star Cooke. I'm buying my 140 heads from him. Expensive, but absolutely rebuilt correctly by a guy with an excellent reputation and spends his days doing this exact work. It's worth the money for the piece of mind.

Man I need to pick up another motor. Maybe I can do my stuff at the same time & we can get a discount confused24.gif Much easier on a machine shop to do 2 of the same right?
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