I can't find the resource infomation but I remember reading that the Corvair engine was originally designed for a tank project.

I have owned 5 corvairs a extremely low mileage 61 fawn beige auto coupe, a 62 white auto 4 dr, a 63 red 4 sp vert and a 65 4 sp coupe. as well as a cherry Greenbriar Van. The only photo I have is of my 65 coupe. The worse thing I ever had to fix were leaking push rod tubes. The smell of burning oil in the heaters were common.

This car was as bad as they get. Scraped down both sides, hit in the front, rusted out behind the rear wheels. I fab'd that air dam out of 18 ga. The paint is a custom mix laquer base red with wild rose pearl sprayed out over the base and the 8 coats of laquer clear cut and buffed. Oh, and this photo s probably close to 30 yrs old.

There is no modification to engine tin. You just need to fab up some tins from 18ga. I made some for my bus starting with cardboard templates, copy-cut out on 18ga with tin snips (or other cutting implement, but I am addressing budget), paint and install. The engine is basically a square.

Mounts are easy to fab because the case is rectangular and has 2 mounting bosses on each side that are free and clear to mate a bar up to with shock mounts.

Its weird how hard it is to find pics of one installed in an 914. In 2000-2002 or so I found one pic and posted on Pelican, can not find it. It has been done before with nice result, but I cant seem to find proof.

If you can't prove it, it's an Alien sighting.

Mike has a history of those

Coupola more thoughts... The only issue with reversing rotation was with the belt life. The alternator (generator through '64) is fixed in place, and doesn't swivel to tighten the belt. This ensures that the belt geometry is fixed on the tension side: crank pulley-to-alternator-to-fan. The moveable pulley that adjusts belt tension is on the slack side: fan-to-pulley-back to crank. This was the case from day 1, obviously, and this is what you lose with a reverse rotation. Other changes over the years- belt guards on the adjustment pulley and just as the belt exits the fan pulley prevent the belt from flipping over. These came along in '64, along with the magnesium fan. The new fan was probably the biggest contribution to belt life, and it's the only fan that can be reversed. The earlier steel fans had curved blades to bite into the air as the fan turned, and they wouldn't work in reverse. All Corvair owners carried an extra fan belt, along with a 9/16" wrench to change it on the side of the road, but with all the improvements along the way, I personally never had one fail me.

Also, another comment about valve train and push rods- many firms offered performance cams for Corvair in the '60's, and all were hydros. It was generally accepted that hydros were necessary in the air cooled Corvair, and all 1.7 million Corvairs built used them. The only exception was an aftermarket cam by Edelbrock, which was for solid tappets. Interestingly, theirs was the only kit with aluminum pushrods. The theory was that though the push rods don't heat up as much as the cast iron cylinders, the aluminum expands more per degree and somewhat equalizes things. Sound familiar?

Any simple ideas for retaining your HEAT if the corvair motor were used in a year 'round dd?

You can reverse the exhaust logs and retain the heater tins. They are easy to adapt since the design is straight forward.

I am working on a new way to get heat from headers.....stay tuned after I get my engine reassembled and installed.

"Girls will be boys, and boys will be girls. It's a mixed up, muddled up, shook up world.............."

In a proposed 914 install, is there anything about the mounting that would interfere with shift linkage? (this is sounding better all the time).

I would think not, however, I have not done it so that is a specific install issue to overcome if is comes up. The engine has very good bottom clearance, better than the TIV with HEs, even.

This is a friend's Corvair race car. The rear fender flares are off of one of the Chrysler K-cars. He's found that the front fenders have exactly the contour he wants not only for his Corvair but also for 914s.

The Corvair engine has been ported to accept the triple Webers as well as P/C and head work. The engine is immaculate and John estimates it puts out north of 250HP.

Brakes are still Corvair standard drum brakes.

something to consider regarding pushrods, the oem GM setup requires the use of a combination head bolt washer/stud plate /pushrod guide so there is a bit of limit to configuration of nonstock parts, not a real problem just something that needs to be addressed if other than stock units are employed.

This is one nice Corvair. It has the 180HP turbo engine.

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This one might end up being a 914vair. He plans to put Corvair rear panel, Corvair engine, and Chrysler K-car wheel flares that he found match the contour of the 914.

No Corvair collection is complete without a Corvair pickup.

Could you run a 911 transmission?

Ya, but you would still have to reverse the engine rotation or it would spin the guts in the wrong direction.

couldn't you flip the ring&pinion, like when a vw trans is flipped to run a mid conversion?

We got a new 63 Greenbriar Van - Blue with White stripes & the vinyl houndstooth looking upholstery - which we drove to CA on old 66 (only small bits of I-40 were started then). I think it only had the base 95 hp motor & auto trans (it was ostensibly Mom's DD), but it fried the valves in TX 1/2 way there & we were stuck while the local dealer fixed it (Amarillo IIRC - I was only 10 then, so fuzzy on the details at 58.5! ).

Great car, we had 6 small kids (2 - 10 yrs), 2 parents & all slept in the car on the way & every summer trip up to 67 - back from San Diego to Pittsburgh - no AC either!

As kids grew, Dad added an Army Surplus stretcher across the 2 back bench seats that folded up against the wall for driving, & open for sleeping. When we grew to 4 teens, Dad moved up to a bigger rig.

Then Dad got a 67 Chevy 3/4 tom pick-up with 327 ci 2 bbl auto trans & towing pkg. with a cab over camper - ahhhh - the luxury, still no AC though!

That will get the output spinning the correct way, but the internal parts of the trans will still be spinning the opposite way of the one they're designed for. They won't be happy for very long, and they will let you know it with expen$ive noi$e$.

The Doc already answered this in the other Corvair thread, I believe. Or was it earlier in this thread?

--DD

Those are great memories. Which jogged mine for some more trivia- Corvair trucks had valve rotators to make them last longer (sounds like it didn't help on yours!) and they also had a transmission oil cooler on the powerglide...

Ya, basically, the input shaft will always be spinning the wrong direction, so the gears will be spinning the wrong direction. Flipping the diff allows for the output to spin correctly, but not the internals of the trans.

When you flip the diff for a 901 to go 911 vs 914 the input shaft and internals all remain spinning in the correct direction as designed, you again change the out put direction only. The internals stay spinning as designed.

Clear as mud?

I understand the internals would be spinning opposite of their designed intent. But just as a mental exercise:

If you install a 911 transmission in a 914 (type 4, etc) you get 5 'reverse' gears.
If you then install a Corvair motor and spin that transmission backwards, don't you get 5 'forward' gears?

It's still running on the 'backs' of the gears, but wouldn't flipping the diff be counter productive?

Jim - at about 13 my first aircooled mechanical experience was helping my Dad change out that tranny oil cooler!

Valve rotators??? I have not seen these, any pics?

I installed the tranz cooler on my PG. It was probably over kill, but I figure I like to floor it over mountain passes, in a bread box, in summer so it couldnt hurt. It was hard to find info on the cooler, it is not common and no pics could be found. I had to consult a guru about how to install and such and still no one could tell me which port is in and which is out.

You are focusing on the OUTPUT only. The helical cut gears would be spun so that their coasting side would then be the power-on side. Not good. You can switch the output of any differential by flipping the diff (if the design allows such), but the ring is being driven by the coast side of the pinion, because the INPUT shaft is spinning backwards of the tranny design no matter what side the diff is on.

IIRC that was an extra cost pick-up & Van heavy duty option with the auto trans (powerglide), and IIRC it had inlet higher than outlet - so you had gravity flow through the fin-box. If that's how you did yours, then it should be okay, so long as the "bread box" isn't so low it gets whacked off on the road.

Is there any other way to drive either a Greenbriar or a VW Bus/Van in the hills/mountains, than to the floor!!??

BTW - the dealer we got it from was out by you Doc - in or near Bridgeville/Upper St. Clair Twp., but don't know if they're still there.

No, I'm not getting that involved. It would blow up, no doubt. But it would drive forward with a 911 transmission. For a few miles anyway.

Small world

I cant remember off hand how I have it plumbed. I have the cooler in the left rear behind the wheel. It is in its own little spot and protected by a mud flap from road debris. If I hit that, something went very wrong. Thanks for the info, no one on the corvair forum could answer it.

When I say that I was flooring it going over the mountains, I mean that I was doing 80mph, up hill Not that I had to do it to make it, just that I could. And that was in a pig-rich running, not quite tuned setup.

I cant wait to see how it does now.

Yes - VERY wrong indeed!

Mom's technique was to speed downhill in the Greenbriar to get a run for the uphill & finish it off at a decent speed. Dad called her "Lead Foot", & she called him "Lead Bottom" cuz he'd never drive over 55 mph - back when 65 was common & TX had 75 speed limits!

I've done that technique with our 88 Westy & stock 2.1L WBX4 + Auto (wife's DD, mine on trips!), but the higher speed running apparently caused it to throw a rod at 85 mph downhill at night in the middle of the CA desert on the return leg of one of our kids & my annual XC trips to Indy, Little Rock, OK & once to Pgh. It only had about 120k then, and that got us a whole new 2.1L rebuilt motor in her - no core refund , but it was before I knew about the GoWesty up-builds.

Your bus on the built up 'vair should haul booty now!

I spent some quality time at a local Corvair house in SoCal today.

Lots of good information and parts avalibility. I was even giving some instructions on how to do the whole thing, sans fab work.

Looking like it do able in the sub $6,000 range.

Head work is the expensive part, Deep Pocket Seats are recommended to help avoid the dropped seat issue.

Lots of motors avalible and looking at the internals seem very easy to build. Of course my CDO (That's OCD for those who don't suffer from Obsessive Compulsive Disorder) would have to be kept in check from not Anodizing or polishing the Aluminum Block, Heads, etc. etc. etc.

In discussing it was suggested to keep the Compression Ratio down to a pump gas level. Use a Cam for a Manual Car, Clean up the ports, Balance everything as close as possible, use new materials for gaskets and viola, AIR-914.

I'm putting a budget and parts list together now, if anyone else is intrested. If a couple people want to do this we may be able to get a nice discount. No promises, but Cash talks, and BS Stinks.

Smitty

How much is the head work? Shop around to the other places that work on these, the prices vary quite a bit. If you have the heads already, Corvair Ranch may be able to beat the locals. $6000 seems high as I did my build for less than that with new VW parts, etc.

Check parts prices against Clark's catalog, then call around and see what you can get for less. Corvair Ranch does beat Clark's prices, most retailers use Clark's as a base and go up from there.

Dr. Evil,

My mistake, I was including the cost of the SDS-EFI two additional throttle Bodies for the FI.

The Motor with Mostly new parts is only around $3,000 and some change.

But that's why I'm making a spread sheet

Valve rotators- can't find a picture, but my 1971 Corvair Parts Master lists them. Part number is 3851837. Looking through the mating parts, the heads are same as in the car, as are valve springs, keepers, and shims. The valves themselves are unique to F.C. (Forward Control- the trucks), and have the note: "Must be used with rotator 3817362." That's a different number than the one listed on the next page! Anyway, the rotator replaces the cap, and is usually thicker so usually the spring is shorter or there is a deeper relief machined in the head or something, but apparently not on the Corvair. Why the valve is different? Don't know.

Also, I found nice pics of the powerglide oil cooler ports in the '61 shop manual. I'll scan them tomorrow. Getting too late tonight....

I also spent the day sourcing Corvair motors. I also stopped by my machinist's shop (who owns a 911 and a 914) and spoke with him about feasibility. He said the Corvair motor rebuild kits (including pistons, jugs, etc) should run $1000-$1500. A quick call to a local Corvair outfit confirmed this, depending on the options wanted. The heads are certainly not the cheapest. Looking around the Internet, I see that some of the vendors that Dr. Evil posted here on the first page have completely re-worked heads for $1200, but I don't see why any competent machinist would have a hard time with them.

I had no problems finding donor motors, or even donor cars, in the $250-$500 range.

Here's the breakdown as I see it yet:

Motor from Craigslist: $300
Machinist charge to check out the block and hot tank it: $50
Rebuild kit (-minus cam, -distributor gear) $1200
Reverse cam $128
Reverse distributor gear $128

I plan to assemble the motor myself, so no labor charge here, but let's say that I bought a shop manual and a rebuild guide for $100.

So far, a bit over $1900.

I guess we'll need the proper fan, but I don't know much they are off the top of my head. I seem to remember that they were cheap.

This leaves the heads. New heads from a Corvair specialist? $1200. Having my machinist take care of them? $200, because the new valves and guides are part of the kit.

$2100 so far.

Then there's the transmission adapter and custom flywheel for $400.

What's left? Fabbing an engine mount, which is extremely cheap for me because I'm handy with a torch and square tubing.

So $2500 for most everything? I'm sure that I'll need to deal with a fuel pump and perhaps go with a nice distributor, but some of the engine kits include new/rebuilt distributors.

Am I missing something terrible? Why the $6000?

-marcus

Marcus, that is the price point that I am more familiar with. You can get rebuilds kits for even cheaper if you use used piston/cylinders. For the head rebuild, yes a good machinist can do it, there are some points to know, though. Crush, staking, depth are specifics that need to be known.

I got an engine, several 901 transmission, a turbo setup, adapter for 901, reverse gear all for $250 on Craigs list. In CA there were many deals. The whole car often cost less than just the engine.

You can usually find everything used for less on ebay and such.

Cam
Dizzy gear
Pistons
Crank
Block
Heads

When I had all the machine work done on my first 3.1 and sold it right before med school, unassembled, I got $1700 on ebay. That was EVERYTHING for a long block.

Great info, Jim. Thanks! I look forward to the pics.

One more thing.

Under the heading of "interesting statistics," I found on www.corvair.org that of the 1.7 million Corvairs produced, 1.3 million of them were manufactured from 1960-1964. From 1965-1969, there were 400,000 produced, the bulk of which were born in 1965. Only 6000 were made in 1969. So while it is more difficult to get a 1965-later engine, they're going to be considerably more rare. I think that the 1964 motor, the serious transition year, would also be a good find. It doesn't have quite as meaty material where the head meets the block and the crank hasn't been chemically nitrided, but you can nitride any crank for $50 the last time I looked. The 1964 motor is still 164ci. What you need to make sure of that if you're out sourcing parts and you're buying rebuild kits, make sure that all the manufacturing years line up. 1964 is also a transition year because the later 1964 engines were actually the 1965 engines, but the 1964 engines still had the early style numbering scheme, so it might be pretty difficult to recognize a '64 motor just by the serial number.

I'm posting this to others who might be snooping out engines and may find this information useful.

-marcus

I shouldn't post because I'm talking out my ass. Pfffphbbrfft.
But another mental exercise:

In both the 914 and 911, the main gear stack is rotating the same direction. The flipped diff is the diff(erence).
So a 911 tranny in a 914 still has the main stack going the correct direction... Just the diff backwards.
Spin the whole thing backwards and that makes up for the diff diff, but the core stack is now backwards.
So yeah, Corvair motor plus 911 tranny = 5 gears forward and 1 reverse... But after all of this shell game, the core stack is backwards... Which is said to be bad?

If two wrongs makes a right, does a wrong plus a wrong plus a right make everything wrong but actually right because it is anti counter productive?

This will make more sense after I have a beer.

People (including me) set up close ratio boxes by installing gear sets in the "wrong" position all the time so that they run backwards. Yes, I know the thrust is in the wrong direction but I've never heard of any problems resulting from this.
Whats the difference if all 5 gears are spinning the "wrong" direction?

It makes sense if you don't think about it.

stock starter would be a problem! it will still turn "the proper" direction....

It mainly is an issue with the pinion/diff. I, too, flip gears for ratios often and that is not a problem, but if the diff/pinion is not turning in the correct orientation it would not be a pretty site. Also, you dont flip 1st. 1st gear is set up to only be down shifted into whilst turning in one direction due to its band and block configuration. Shifting from reverse to 1st real fast is one way you can try what it would be like to shift into first with the box being turned the wrong way. With first running backwards, you would be prone to popping out of gear as the band would not be reinforced by the internal mechanisms of the synchronization package.

The way I explained it made sense to me. I just wasn't sure I had it right.

I'm not convinced that running the R/P backwards would hurt it.
Reversing the brake band/block on first is easy, no need to even disassemble the gearbox.
I don't know if how the bearings are retained in the case would be a problem though,
but the starter appears to be a significant issue.

wish i'd known about this before buying all the kit pieces to convert to sbc.

this is a relatively minor concern but, what kind of fuel economy can be had from corvair motors?

paul

Interseting read, this thread is. Was cleaning out my bookshelf just last month and threw out a copy of HP Books "How to Hot Rod the Corvair." Would have gladly donated it had I known.

'66 Corsa was fast. Easiest mod was to wrap the exhaust to get more boost. There was also a 2bbl down draft carb manifold (Crown?) that used a 2G Rochester if I remember correctly. Ran 126MPH (standing start mile) at El Mirage at a time when 911's would struggle to break 100MPH.

Andys

If anyone is interested, I have a holley carb adapter with an almost new 390 Holley for sale. I had CIS for this engine and just decided to go that way.

You also have to consider the thrust loads on both the input and pinion shafts of the 901. Turning in the correct direction, the helical cut gears on the shafts push the input and output shafts in different directions. When you reverse the input rotation, you change the thrust load. That makes the thrust bearings engineered into the transmission irrevelant, and the thrust load happens against surfaces not designed to handle it. It also changes the backlash on the ring and pinion combo. When there is load on the pinion gear, it climbs the ring gear slightly. When you reverse it, it will not climb the ring gear, changing the backlash and affecting both the life of, and the noise from the gearbox.

Yes, it would work. But no, it won't last long. The extra horsepower of the corvair engine, combined with the incorrect thrust loads will make quick work of the transmission.


FYI.. the reason the corvair engine turns backwards is that the corvair gearbox was a modified saginaw 4 speed that had a hollow main shaft so they could put an extra long input shaft through it's middle to connect it to the rear mounted engine. And the differental assembly is a standard 10 bolt diff that was found in everything GM made. So they made the engine turn backwards so they didn't have to make all new gearbox pieces.