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Corvair Aircooled 6 cyl in a T3
Posted: 11 Dec 2008, 01:00
by Vanagonman
Those who don't know, GM made Chevrolet Corvair in the 60s with Aircooled six-cylinder engines. The most ideal one was a 110hp model, which makes power effortlessly (although Chevy did make a turbocharged 180hp one). The advantage of using these is that they sell used engines for around £300 and parts are cheap and available (unlike the more expensive Porsche). The engine runs in reverse rotation, so usually one can reverse the rotation to match the VW and use a gearbox adapter, or use a Corvair gearbox and use halfshaft adapters and adapt a shifter linkage.
This is an email with pics from a friend of mine in America who's working on installing one in his T3. Many already exist in Splittys and Bays, but this is the only one I know getting the 'T3' treatment.
Actually looks like it fits in there like a glove. My friend Vern in America who's doing this wrote:
The differential is finished - 3.89 ratio, 4-spider positraction.
The T5 is ready to go (He is using a non-standard, rare 5-speed - the usual Corvairs come with 4 speeds or 2 speed auto which are easier to bolt in). I had to re-engineer the sucker. With the help of a
local machinist friend, I replaced the two front bearings, one of which I
had to get from Lamborgini in Italy. Most of the other modified-T5 owners
are adopting my fix, so I guess it is worthwhile beyond my application. I
also sealed it from the diff so I can use ATF in the trans. I'm much more
comfortable with it now.
The engine compartment is finished.
Right now I am working on the shift linkage. The Vanagon shifter doesn't
seem to impart much 'twist' to the rearward links, so I am installing a Vair
truck shifter in the front and am using the Vanagon tube bits with a couple
of u-joints at the trans.
I think a conversion could be done more easily than I am doing it, use of
the T5 5-speed made it necessary to use the spread-front, center-rear
mounts. I think a center-front, spread-rear method could be used with a
stock 4-speed without the problem of the intrusion into the cabin.
The rear mount is a '65 Vair car, it is bolted through to the receiver hitch
for strength. The gap around the engine shrouding will be filled with a
stock Vair engine seal.

Engine & Gearbox as one assembly awaiting install

Engine from below. Looks like a stock install, eh?

Bird's eye view of install

Cutout top make room for pesky 5-speed T5 gearbox (not needed for the stock 4 speed)

Install looks stock and look how much clearance room is left!
Re: Corvair Aircooled 6 cyl in a T3
Posted: 11 Dec 2008, 08:26
by toomanytoys
Mmm.. thought about this... would be quite cool, its quite a good engine, didnt think there would be many about now though... as it wasnt a sales success... (it wasnt a bad car either, very advanced for its time...)
keep reverse rotation swap the diff to the other side.. easy... or if all the correct rotation parts are cheap!!!
Hows the cooling fan driven? drive off the middle of crank?
Re: Corvair Aircooled 6 cyl in a T3
Posted: 11 Dec 2008, 11:10
by regurgevole
Cooling fan is driven from a harmonic balancer off the end of the crankshaft, and a belt arrangement that turns 90* so the fan can be run horizontally. The belts are semi-notorious for flipping out of the guides. It's a fussy arrangement.
I owned 2 corvairs, a twin-carb 110 hp engine, and a quad carb 140 hp engine. These are the only Corvair engines worth a damn, and were only made from 1965 to 1969. Stay away from the smaller 1960 - 1964 engines.
Carbs are a nightmare to keep balanced, lots of slop in the original factory linkage, and that won't be improved with 40 years service life later. There are people who switch to fuel injection, and THAT would be the sh!t, but a lot of work. The intake manifolds are cast integral with the heads.
140 hp engine had bigger valves than the 110, which would be preferable, except the seats slip (primitive aluminum head & steel seat expand & contract at different rates - aluminum heads were not ready for prime time in the USA in the 1960s). However, staking the around the seats with a punch can stave off the inevitable for the 140 engines. The 110 never had this problem.
Turbo engine was 180 hp, but pretty primitive - it was only the 2nd production car on the planet with a turbo, it's carburated, and it has no wastegate. No boost until 3000 rpm, so pretty useless as a daily driver. Very hard to start in cold weather.
All Corvair engines are heavier than you want them to be.
Re: Corvair Aircooled 6 cyl in a T3
Posted: 11 Dec 2008, 11:57
by Vanagonman
Apparently the correct fan belt makes a big difference in whether or not the belt slips off. If tuning the carbs/linkage is an issue, you can always get an intake manifold that supports one big single carburator which makes it easier to manage.
As far as engines are concerned, there are many flavours. Even the most basic engine, early iteration will provide 80 hp and more torque (remember it's a six cylinder) than any VW four did. While the 110 hp later model is most ideal, I wouldn't *avoid* the earlier ones either. Just that if you were going to get one, it's best to get the 110 version.
I must say I'm a bit biased now, as I just purchased one engine including four speed gearbox out of a Corvair van (vans were only produced early on, hence an early engine). The good news is the van-version of the engine is essentially the less powerful version of the 110hp motor (98 hp).
How much did it cost me? Appx. £60 for
BOTH! engine and gearbox. Of course I have to ship it over here, etc. But it would still be much cheaper than another Aircooled six that shall remain nameless!!
Re: Corvair Aircooled 6 cyl in a T3
Posted: 11 Dec 2008, 21:33
by billy739
looked into this years ago for my beetle!
reverse camshafts pop up on ebay sometimes.
theres a bloke down the road who is a hoarder , his house is overgrown and he has a row of cars (about 6) along his drive way all way over grown random stuff , renaults ect BUT at the front is a corvair with one of these in it!
apparently the engine was rebuilt shortly before being parked up about 20 years ago!
the blokes on deaths door with illness so keeping an eye out , but i bet it will just get sent to the scrappy and crushed!
Re: Corvair Aircooled 6 cyl in a T3
Posted: 11 Dec 2008, 22:02
by Vanagonman
billy739 wrote:theres a bloke down the road who is a hoarder , his house is overgrown and he has a row of cars (about 6) along his drive way all way over grown random stuff , renaults ect BUT at the front is a corvair with one of these in it!
apparently the engine was rebuilt shortly before being parked up about 20 years ago!
the blokes on deaths door with illness so keeping an eye out , but i bet it will just get sent to the scrappy and crushed!
I would go there and offer him £500 for it and see if he accepts. Chances are he's in need of ££ with the price of heating increases, etc. You never know unless you ask.
Re: Corvair Aircooled 6 cyl in a T3
Posted: 12 Dec 2008, 04:48
by regurgevole
Vanagonman wrote:If tuning the carbs/linkage is an issue, you can always get an intake manifold that supports one big single carburator which makes it easier to manage.
Those centre-4-barrel setups on long tubes work crap for driveability. (And E D I T - your photo is not a new intake manifold, it's a bodge of tubes that bolts to the carb mounting flanges of the original intake manifold/head)
Fuel injection is really the only way to go if you get fed up with the single barrel Rochester carbs. Megasquirt is now so cheap as to be almost free. Back in the day, the REAL answer was tripple Webers, but that meant serious machine shop work to cut the intake manifold off the cylinder hear - as I said, it's cast in 1 piece. Dig this mod:
Vanagonman wrote:I must say I'm a bit biased now, as I just purchased one engine including four speed gearbox out of a Corvair van (vans were only produced early on, hence an early engine). The good news is the van-version of the engine is essentially the less powerful version of the 110hp motor (98 hp).
How much did it cost me? Appx. £60 for BOTH! engine and gearbox. Of course I have to ship it over here, etc. But it would still be much cheaper than another Aircooled six that shall remain nameless!!
It's
not just a "less powerful version of the 110 motor", it's actually a different engine entirely.
You bought the 145 cu.in. engine block, not the 164 cu.in engine of the 1965 and later Corvairs. The 164 cu.in. engine is superior in every way to the earlier engines.
The shipping costs on that boat anchor are going to kill you.
Seriously dude, you're making a huge mistake. Chalk that £60 up to experience and let it go.
If you are intent on a Corvair repower, enough so as to pay the shipping to the UK, and do all the mods to get it into your van, then you need to buy a 164 cu.in. Corvair engine, either 110 or 140 hp., preferrably the 140 hp (with staked valve seats). They're not extremely expensive, and they come up reasonably often if you look around Corvair clubs & forums in the US and Canada.
Re: Corvair Aircooled 6 cyl in a T3
Posted: 12 Dec 2008, 08:15
by syncropete
All this for 110 bhp

Re: Corvair Aircooled 6 cyl in a T3
Posted: 12 Dec 2008, 08:39
by Vanagonman
syncropete wrote:All this for 110 bhp

More horespower (up from 67 hp) and more importantly, a ton more torque!

Torque is what gets you up those hills!
I hear what your saying about the early Corvair motor, but I'd rather have the 'boat anchor' to mess about in my garage and spend hundreds shipping it than spend thousands on a 911 motor and thousands more if any parts were to go bad. Once I have it placed in, converting to a bigger displacement Corvair engine will be a walk in the park, and yes, there are good Corvair motors to be found Stateside. I think of it as a mock install and trial to bigger and better things.
Oh and...
regurgevole wrote: (And E D I T - your photo is not a new intake manifold, it's a bodge of tubes that bolts to the carb mounting flanges of the original intake manifold/head)
Odd, as the words "intake manifold" are used by others for just such an item:
Search item number 180312442119 and item 170285353289 on Ebay
Hey! How about we call it a "carburator manifold" like Clark's Corvair calls it... Cool?
You are technically correct, but it's just easy to call the thing an intake manifold. Can we now continue from the lesson in semantics? OK, thanks...
Excuse my American sense of humor

As an American, I'm cursed/blessed with it.
Moving on...
I just spoke to a guy selling a custom 180 hp naturally aspirated Corvair engine out of his Dune Buggy he's selling last night, that I may buy off him at some later point for £700.
So far, the Corvair seller I bought off Ebay hasn't responded to my purchase, so I may not end up with it after all. Who knows??
Re: Corvair Aircooled 6 cyl in a T3
Posted: 12 Dec 2008, 08:56
by Titus A Duxass
I can't see the point of changing one lawnmower engine for another!
Re: Corvair Aircooled 6 cyl in a T3
Posted: 12 Dec 2008, 09:27
by Vanagonman
Titus A Duxass wrote:I can't see the point of changing one lawnmower engine for another!
And I don't see the point of antifreeze-leaking head gaskets, worrying about coolant issues thanks to 43 different coolant hoses/pipes (in a WBX), and coolant air locks either (Subaru/WBX). Your point??

Re: Corvair Aircooled 6 cyl in a T3
Posted: 12 Dec 2008, 10:22
by ringo
As an Englishman not into american cars i had no idea what you are talking about. I found this:
Pretty damn cool!
I dont know how you could go without heating - but i suppose its what your used too.
I admire what you have planned but i dont pretend to understand why someone would want to put an older engine in!
Anyway, best of luck and keep us informed..
Ringo
Re: Corvair Aircooled 6 cyl in a T3
Posted: 12 Dec 2008, 12:22
by jamesc76
Vanagonman wrote:Titus A Duxass wrote:I can't see the point of changing one lawnmower engine for another!
And I don't see the point of antifreeze-leaking head gaskets, worrying about coolant issues thanks to 43 different coolant hoses/pipes (in a WBX), and coolant air locks either (Subaru/WBX). Your point??

To be honest i like non original engines in these vans esp. when done all at home and not by buying it all off the shelf or paying someone to do it for them,
BUT If you fit /bleed the coolant system properly you shouldnt need to worry???????? They only leak if you just leave them to rot or your no good at seeing faults!
Re: Corvair Aircooled 6 cyl in a T3
Posted: 12 Dec 2008, 15:44
by Pepperami
WEIGHT!!! It looks like the carbs alone weigh more than a WBX.
Re: Corvair Aircooled 6 cyl in a T3
Posted: 12 Dec 2008, 15:54
by Vanagonman
ringo wrote:I dont know how you could go without heating - but i suppose its what your used too.
I admire what you have planned but i dont pretend to understand why someone would want to put an older engine in!
Anyway, best of luck and keep us informed..
Ringo
Thanks Ringo. Well we Yanks have been putting older 60s engines in our newer cars for decades (even though we're not really allowed to by law in many areas) in order to gain simplicity, power & torque - not to mention the lovely sound of a bigger displacement engine (check out this late 60s-early 70s 7.5 liter engine in this 1986 Olds - Ebay item 270314633837). As far as heat is concerned, nothing a Propex heater can't help with!!

You do realize Aircooled 911 Porsches produced until 1996 had heat right??
Pepperami wrote:WEIGHT!!! It looks like the carbs alone weigh more than a WBX.
LOL. The engine actually weighs less or about the same as the Type 4 motor it's replacing! Not bad for an extra two cylinders.
According to this chart
http://rabbitsformeat.com/engineweightchart.txt" onclick="window.open(this.href);return false;
the Chevy Corvair engine weighs 300 lbs. while the VW Type 4 weighs 311 lbs! The reality is more or less the same.