Shifting gears.

The Corvair shifter has gained something of a reputation for not working very well, partially due to the fact that some of the parts aren't terribly durable. There are basically three different parts to the shifter - the lever mechanism, the shift rod, and the coupler, so I've broken this down into these three pieces. Although they are similar, early and late models use different setups, so I'll cover them separately. As with some of my other pages, this is a compilation of information from members of Virtual Vairs as well as my own writings.

Lever Mechanism.


The lever mechanisms themselves are quite similar for all years of cars, here are some general notes. The shift knob uses a 5/16-18 (SAE coarse) thread.

From: Mark Domzalski

If you rebuild a differential, save the tapered rollers from the side gears. They can be used to replace the side pins in your shifter when you rebuild it.


From: Chuck Sadek

The shift mechanism depends on the rod coming out of the trans rotating the proper amount as well as going in and out. The hard part is the front, assuming you have removed the slop at the rear in the coupler. The shifter base is cast with a spherical surface on the inside/underside of the "top" portion - where the shift lever comes thru to the shift ball/handle. This mates with a more or less spherical piece pressed onto the shift lever inside the cast base. It has grooves in it which fit pins pressed into the base. These wear - another source of problems. Underneath, there is a spring and a more or less spherical sheet metal retainer that is pushed into the spring and turned to fit in retaining grooves in the cast base. On the bottom end of the shift shaft is a spherical ball - which wears (a source of problems as you'll see). The ball, sticking down from the underside of the cast base has to be at a specific length to fit into the front of the shift rod/tube running to the coupler. There are two versions of the front of the tube 'housing'; one stamped and welded steel and one of what looks to be brass. They can also wear but not usually much. Both work the same with the lower shifter 'extension' with the steel ball on the end.

In order for the ball and lever action to turn the shift rod rotationally, the ball must be at the right height in the shift rod tube housing. Think about it. Therefore the shims under the cast base to get the (lever) length right in relation to the stamped outer shift rod tube (housing) front - where you put the front bushings. Therefore, the wear points are the lower portion of the shift lever (ball), the retainer, the pins in the cast base, and the tube housing. These plus incorrect thickness of shift base shim stack are what cause problems.



Early 3 speed shifters are faster ratio than 4 speeds, so a quick upgrade is to use a 3 speed unit. If you want the nice chrome handle, the ball can be pressed further up the shaft of the 4 speed lever to match the 3 speed's dimension. Then use the 3 speed base.


From: Seth Emerson

We used to call the early Van shifter's "Guess-a-gear". Seriously I have used aftermarket quick shifters on late models. But why don't you use the late model "Factory" quick shift kit? It is hard to find but easy to identify. How you ask. The trick is to use the shifter from a 1965 3-speed. This black painted shifter has the pivot ball located higher on the shift lever, decreasing the mechanical advantage and shortening the throw (relative to the chrome 4-speed shifter.) It should be used with the 3-speed cast housing, (although a correct adapter could be built, it hasn't been.) Look for the black painted shift lever, not Chrome! Lots of earlies had a similar look, but are different and won't fit, I'm told. I have used the 65 3-speed shifter in several cars, among them my last Yenko autocross car, and my current Corsa Convert. It can be adjusted using all the factory floor shims, no need to bolt solid to the floor (a bad idea). The shifter "system" should be treated as a "system" and not addressed with band-aids.


Reverse Lockout - this should work on either an early or late shifter.

From: Andy Clark

I put just such a device on Orange Julius when I was racing him. I drilled a hole in the ball of the shift lever and had a spring-loaded pin with a link up to a "T" handle mounted on the front of the shift lever. Pulling the "T" handle pulled the pin out of the ball and allowed the ball to rotate to the left far enough for selection of reverse. This prevented the dreaded "can't get 2nd" syndrome in the heat of battle. Particularly on the 3-2 downshift.


Shift Rod.


Not much here. This is because the early uses a shift assembly bolted to the floor with the rod only supported up front. There is no outer tube as on the late. Simply bush the front rod support and you're done.


The big key with the late shifter is to make sure both the inner and outer tubes are straight and clean before you start. Get all remains of the cardboard liner out of the outer tube, and make sure both have as little rust as possible. Here are some more tips.

From: Ray Sedman

I remove the liner, clean the tube and the rod then slip a 52" length of 3/4" I.D. schedule 125 (thin wall) PVC pipe down the tube. Grease the shaft up real good. You will not believe the great feel of the shift linkage after you do this. You can also use the thick walled PVC, but you need to run a 'slice' the full length of the PVC to allow it to be inserted into the tube.


From: Bording Ostergaard

Done right, this will make your shifter feel just like a "top loader". I also sand the inner tube nice and smooth and then put a light coating of grease or corrosion inhibitor on it. Not too thick though or cold weather will make your life miserable.


From: Seth Emerson

Most people I know remove the cardboard lining from the outer tube. Often it is replaced by some appropriate PVC tubing. The purpose of this lining is to stabilize the rod for it's long length. I install the Clarks Bronze (Brass?) shifter bushing kit in both end of the outer tube. At the rear of the shifter tube, there is a coupler which attaches the shifter to the transmission crossmember. The stock setup uses a pair of rubber grommets to isolate the shift tube from the power train movement. I replace these rubber grommets with Nylon sway bar grommets (From a Camaro/Firebird).

Finally use the available shim kits to make sure that you have minimized the clearance where the shifter mounts at the floor. BUT - don't bolt it to the floor, you should only capture the floor between shims. IF you bolt it tight to the floor, when the engine/trans shifts fore and aft, the trans can shift out of gear on it's own. Oh, yeah - remember to re-install the lower pan cover over everything. This will keep your newly lubed assembly cleaner.



Although they are slightly different in length, the '61 to '69 couplers can all be modified using these instructions from Seth Emerson. The early '60 couplers are different (like all things '60 :-) and have a u-joint in the middle so this won't work.

I use an old coupler (that's the part which finally attached, via a pin, to the transmission shift rod) The stock coupler has rubber molded into it to retain the two pieces. One piece is the rod that is clamped into the long shift rod that heads up to the front. The other piece is the stamped steel tube which extends back to the trans rod. In the midst of the rubber is a pin which is pressed into the rod and floats in two holes in the tube. I clean off the grease on the coupler and weld both sides of the tube to the pin. This makes the coupler solid. At the back of the coupler there are two holes (actually they are short slots.) The pin that attaches the coupler to the trans goes through these holes and is retained by a cotter pin. The slots in the coupler are usually worn, as is the pin. Buy a new pin (plus a spare, they're cheap!) The hole in the transmission rod almost never wears - It is case hardened. The slots in the coupler do wear, even though they are semi- hardened too. I drill out the slots and use a thin bronze shoulder bushing in each hole. The i.d. of the bushing is the size for the pin to go through. The bushings available fit the drilled out hole fine, but are too long and must be trimmed to fit. In order to drill out the slots in the coupler to round, you must soften them. Heat them till they are bright red then let them air cool (this will piss off the rubber in the coupler big-time, be ready for smoke!) After they air cool, you should be able to drill them. Drill them to the outside (of the shoulder) diameter of the bushing.


Now that you know how to modify a coupler, there is another alternative, recently developed by Ray Sedman. It's a fully machined aluminum replacement with no rubber connections - this coupler uses a u-joint instead and should work in any '61 and later shifter and will eliminate the slop of the stock coupler. Take a look over at the American Pi site for more information.

Forward Control.

The FC shifter is similar to the car shifter, but most of the parts are different and there are two varieties. Here's a post from Jim Davis outlining how to make the early type better - this is the one that comes out under the seat. The late FC shifter is on the floor and has the linkage through the gas tank. And yes, people do autocross FC's!

Contrary to popular beliefs the early FC shifter can be made solid. There are three critical wear points that should have virtually no play. First is the bushing in the shifter support assembly. It is not serviced but a steering gear, pitman shaft bushing is almost the correct size. It is a little long and slightly oversize. Press out the old bushing and file down surfaces where the new bushing is split until it is the right diameter. I use a rotary motor tool. Press in the new bushing and cut to length. You will have to redrill the bearing for the grease fitting.

Second is the shifting tube support assembly. Out there somewhere are the Moog replacements for the stock. I find them at swap meets. They are longer than stock and have a removable sleeve bearing. This is a standard oilite bearing which I buy from Coast-to-Coast. Again the hole will have to be drilled in the bearing for the grease fitting.

Lastly is the pin in the coupling assembly. I find that it is a really sloppy fit in all Corvairs with some mileage. The fix requires two procedures. With the coupler removed, drill out the pin hole to 3/8 inch. Next drive in a 3/8 inch roll pin (tension pin) into the coupler. With a motor tool, cut of the roll pin to the right length and then cut out the center to provide an opening for the transmission shifter shaft. That will take out about 60% of the shop at that point and a pair provide a hardened steel bushings for the shifter pin. I find that the replacement shifter pins are about 0.06 undersize. I take a grade 8, 5/16 by 1 and 1/2 bolt and file it down to the correct size. I use a drill press and a mill file. The bolt head can be shaped by a grinder. After it is filed to the correct size, place it into the coupler to measure where to drill the hole for the retaining clip. After the hole is drilled cut off the excess length. You won't believe what a difference it makes.


Corv8 notes.

From: Tom Piantanida

I've owned several mid-engined Corvairs. My favorite was a Kennedy Engineering Products adaptation of the aluminum Buick 215 V8 to the Corvair transaxle. The installation required flipping the transaxle fore and aft. The only problem I ancountered was with the shift linkage. The installation reversed the shift pattern and resulted in some ambiguity as to which gear you had actually slected. The solution was to get the side cover from a Saginaw 4-speed used in anything but a Corvair. The side cover bolts right on and has shift forks that mate perfectly with the Corvair Saginaw. A shift lever/mechanism from a Vega was bolted to the Corvair pan and communicated with the shifter arms of the Saginaw via Morse cables. The shifter arms for all of the forward speeds can be inverted, but the reverse shifter needed a bell crank. You also need to remove the old shifter rod and plug the hole in the Corvair Sagimaw. - Tom Piantanida


From: Chris Wills

I wrote the article in the V8 Registry. I believe cables would work well, IF the right cables are used, i.e good marine-type push-pull cables. The biggest problem will be fabricating brackets to hold the ends of the cable outer jackets near the shifter and the trans side plate. The shift rods don't move in a straight line but follow an arc, so depending on how close you mount the ends you may have to allow the ends to pivot to prevent binding. IMHO, I think it might be easier to use rods and keep them above the crossmember, and mount the shifter above the floor (in a console?) so the rods are also above the floor pan. Or use a bellcrank arrangement to put them down in the tunnel just in front of the crossmember. However you do it, you will love the direct feel when shifting.


Care and Feeding.

Transaxle fill

From: Frank Burkhard

I prefer a synthetic 75W-90. When I first got my 65 turbo Vair, the shift to 2nd gear was very difficult on cold mornings (note: Frank lives in New Jersey, so cold is freezing or below). Switching the oil to Amsoil Synthetic 75W-90 completely eliminated the problem. Look in the shop manual for the quantity you need. I use a vacuum jar to suck out the old oil and pressurize it SLIGHTLY (10 psig is PLENTY) to pump back in the new oil.


Saginaw ('66 - '69) four speed into '65 stick shift car.

Q: The '65's used a different 4-speed trans than the '66-'69 models, correct? If so, will say a '67 4-speed swap into a '65 4-speed car with no physical alterations? Does the shifter rod and everything line right up? What is the benefit of the later model trans & is the swap of much value in a street driven, stock 140?

A: The later trans is about 1" longer than the '65. You will need to swap in the later trans crossmember, the input shaft, the shifter support rod and the end bracket from a 66-69 (this is the rod and bracket that connects the rear end of the shift tube to the trans crossmemeber), and if you want to use all six trans to diff bolts, the differential (or at least the case). The shifter clevis needs to go in the tube a bit more, you may be able to do that without trimming the tube. I did this swap on mine, didn't have to trim it.

I don't think it's worth bothering with on a stock 140 - the diff is the weak link, and the differential is the same (except for the two extra bolts to the trans). Of course if you have a three speed and want to go to four, then you might as well put in the heavier duty trans.

Spider gear shimming.

From: Jerry Bullis

I shim the differential side gears into the spyder gears until they slightly bind when turned. The binding doesn't hurt anything since the gears only move in turns and don't get hot. It does remove the slack from the gears and is the only way I could keep a 4 spyder diff from breaking he spyder gears in my dune buggy. I also use the same setup on my '65 coupe.

For the first couple of days, the gears in the coupe made a little noise during turns, but rapidly wore in and quieted. Changed the oil after 5K and found very little indication of metal. I have combined miles of well over 150K. I have had the diff out of both vehicles and could see the side and spyder teeth had worn to closely match each other. The teeth were obviously shinier due to wear, but no longer bind. The car had 110K miles and the gear slack was still minimal. The coupe puts out about 280HP at 6400 RPM and can chirp the tires going into 3rd at 65MPH.

Haven't had a diff problem with either vehicle since I shimmed the gears. Sure beat changing out spyders every other year in the dune buggy.


RPM drop and Top Gear RPM tables.

Patrick Caherty came up with a spreadsheet that had the RPM drops as you shift up through the gears of the stock late model transmissions, I've added the modified close ratio boxes and converted it into a web page. Matt Nall supplied me with a table for RPM at 60 MPH given tire size and final drive ratio.