Marcus' Corvair conversion, 914-C6 Options

[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 (IMG:style_emoticons/default/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 (IMG:style_emoticons/default/sawzall-smiley.gif)

Ill enjoy watching the build. (IMG:style_emoticons/default/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.



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





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.



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



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



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.



Then the oil cooler.



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

[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.



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.



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.



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.



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



Off come the bottom head nuts.



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.



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



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.

[r3dplanet]

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



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.



Off with her head!



Yeah. She's had some wear.





Cylinder #5 has quite a bit of bonus debris. (IMG:style_emoticons/default/icon8.gif) Doesn't matter. These cylinders and pistons are headed straight for scrap.





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

[aircooledtechguy]

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!! (IMG:style_emoticons/default/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 (IMG:style_emoticons/default/biggrin.gif)

[JRust]

Oh man what have I done (IMG:style_emoticons/default/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 (IMG:style_emoticons/default/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]

(IMG:style_emoticons/default/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 (IMG:style_emoticons/default/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 (IMG:style_emoticons/default/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.

(IMG:style_emoticons/default/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 (IMG:style_emoticons/default/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.

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.

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.