so the regular corvair of my year is 145 cu in flat 6 which has 84hp and that doesnt cut it for new roads (2.3l) an id like to bore to to be 200 cu in but i want it to be structurally sound and can stand high heat withought warping so id like for you guys to give me your two sense and say what would be the max bore on a corvair safely
There are performance Corvair guys that build bigger engines. They use VW cylinders ( modified ) to give you a 3. 1 liter ( 186 Cubic inches ). Around 200 HP. Your best bet is to find a 164 cubic inch Corvair engine with the 4 one barrels. There is always a V8 conversion
Put a later 164 engine in it, and get it running and geared right...put a 4 speed in if it has the powerglide now...and drive it, and you'll probably find it works ok keeping up with traffic. You can add the turbocharger if you need more. Or spend $6k or so building a 200 ci motor....
When my dad worked at Kirsch Chevrolet in PA, he had a good friend who was one of the salesmen... HIS son had a thing for Corvairs (still does) and added a late 60's M--stang chin spoiler to help keep the nose from lifting at 100mph on his trips to and from NYC in the 70's The 164 is your cheapest bet, but cubes aren't necessarily the issue (my 2.4l daily H--da Element is quite capable on the highway). Better carburetion, 4 speed trans, and gearing are your friends in that battle!
It may be sacrilegious to suggest.... Has anyone though of a Subaru flat four engine is one? They make a ton of power and are cheap and easy to get. Water cooled tho, so running a radiator up front would be needed. But at least they don't have that oddball twisted fan belt to deal with.
When we ran Corvairs in the sand, we built two 110 HP engines. Put the 140 heads (4 carb), milled the heads .080, and bored the cylinders to 3 9/16". The both ran like raped apes. Also did mods to the cases to improve oiling and put in the high volume oil pump kit.
Good grief, if I'm going to all that bother, I'm putting a V8 in the back seat, not some import 4-banger.
I was just leafing through Hot Rod Magazine Sept 1968 which has an article on Ted Trevor using one of his Crown Manufacturing kits to install a 327. Coincidence? I think not
Might be the way... https://grassrootsmotorsports.com/articles/subaru-wrx-powered-corvair-low-buck-tech/
There is a V8 Registry for other motored Corvairs. There are some Honda powered, some Subaru powered , a couple of Nissan powered. Bunches of crown conversions, Kelmark conversions and Toro conversions. Mine is a toro conversion but with a SBC instead of Olds or Caddy.
Was it Bill Thomas who made a kit to put a chev v8 in the back seat area? Saw one at a car show once, must have handled pretty good.
Well, it was just a thought. Most likely way less work than building out a chassis for a front or mid motor. And they make really good power.
Ralph Nader said the Corvair was "unsafe at any speed", wonder what he'd think about one with a V8 swap? LOL
Well I guess if they are unsafe at any speed then a bigger motor is just as "unsafe" as a stocker.LOL
The funny thing about increasing displacement a lot is that it may not increase power very much at all. Big lungs are just one part of the equation, you need to have carbs, intake, valves, ports, camshafts, exhaust manifolds etc. that breathes so much better too, otherwise you may just be moving the same peak horsepower to a lower rpm. On low rpm there's enough time to fill the cylinders completely. Peak torque rpm is the rpm where the engine breathes best and works very well, the torque is highest because the pushes the pistons down with the most force. As the rpm goes up more the breathing begins to restrict the engine, the cylinder aren't completely filled any more. But despite the torque dropping, the cylinders fire more often, so the total work (i.e. power) still increases as the rpm goes up. Eventually as rpm goes up you get to the point where cylinder filling begins to drops off faster than rpm goes up, that's the peak hp rpm, and any higher rpm will just reduce the power. So, let's take that 84hp engine, I don't know what rpm that is as but just for arguments sake say it's 5000rpm, with a torque peak at 3000 . Let's double the displacement, with no other changes. The carb, ports, valves etc. can't let much more air through in the same time, so when the cylinders previously could be filled completely @ 3000rpm you need the same amount of air to fill them completely at 1500rpm. The bigger displacement may be able to put a bigger vacuum at the carb for a longer time, so the engine can get a bit more air through in total, so the max power can increase a bit, but nowhere near as much as the displacement change would imply. I'm not saying large increases in displacement have to be a bad idea, I'm just saying that big lungs are useless if you are unable to fill them properly. On some engines you can easily substitute better cylinder heads that flow way more than the original could ever be modified to do, on other engines the original heads respond well to bigger valves, porting etc, and yet other engines can't get enough flow to work well with the biggest displacement they can be modified to, do such large displacement would be wasted. It's a bad idea to just go for big displacement and assume everything else will just automatically work well with that. It will work, sure, but you may build an engine suitable for a tractor, so it runs into a wall any time you try to use higher rpm because it can't breathe.
Since my Subaru suggestion fell flat, I will offer up some other comments. I have a lot of experience in air cooled flat four cylinder engines of an unmentionable make on this forum. My current drag race car, (actually, my son's now, as I handed it off to him early this year) makes nearly 500hp out of 132 cubic inches. Turbo charged, mechanical injection on methanol, and with only 9-1 compression and a valve lift of less than .500". It's only the fuel (and the mechanical injection) that makes it impractical for the street. But street legal it is. Now, with increased displacement, come increased heat production. Can the stock Corvair cooling system handle it? Maybe, just maybe, turbocharging is your answer. A mild set-up can easily double the power and be on tap only when the long pedal or the right is mashed down. Otherwise, fairly passive, and the mild mannered driving characteristics are retained. They did, after all market a turbocharged version of the Corvair, so it ain't like it's breaking new ground.
I don't think your suggestion fell flat at all. Although it has been done several times, it is a great way to gain all wheel drive with the power the little boxer engine puts out. With the Subaru being fuel injected, I might hang back from that swap versus a carbureted engine. The weight savings alone make it a good candidate for a swap. The Corvair fan was always the weak point with the car's engine design. The way the fan is made, it actually produces a positive pressure forcing the air into the fins. Chevrolet changed the rear suspension in 1961. The original design was a copy of the VW rear suspension. The change that Chevy made to the Corvair rear suspension showed up in the 1963 Corvette........... The front suspension of the late model is almost the same as the Camaro front suspension might want to rethink your statement
I daily drove a 1963 2 door coupe with the 110 horse dual carb motor for about 5 years, about 10 years ago. It was no powerhouse, but did have plenty of scoot to get down the road. It doesn't take much in a lightweight vehicle. Devin
There's some guessing going on here from those not familiar with Corvairs...The Corvair has a fairly robust engine with a smooth 6 cylinder sound... the usual hot rod tricks can give 150 hp and won't cause a lot of stress... Best idea is Google and check out the Corvair forums for practical ideas.
With many 1000's of dollars you can put a Jaguar V-12 n a Corvair. http://www.corvaircorsa.com/V-12-01.html A great read but impractical for 99.99% of Hamb members. I had many Corvairs from 1974 to 1995, all had the 164 cu in 110 HP 2 carb units, and all had the Powerglide trans. A very light car with a decent engine, it was good enough for me. Dave
Mt wife and I both daily drove late models for years. Including several multi-day road trips on interstates. Her car had a 102 HP 2 carb engine (smaller cube displacement). the trick is 4-speed, 3:27 rear gears, and taller tires (hers was 15" wheels and 205 60/15's). It cruised out just fine on the interstate at the 70+ speeds we run here and had a lot of grunt with a 4 speed for commuting. Very fun car for around town driving. My car was a 140 HP 4 carb (bigger cube displacement) with an ultimate carburetor kit (Clark's Corvair double Weber two barrel kit) a stage one cam, 3:55's and a 4 speed. Same final tire height as the other car. This one drove the same, but had more pull at the top end and sounded angrier. My point is on a Corvair the best bang for the buck is gears, 4 speed, and tire height. The best two factory configurations are the 102 and the 140, unless you want to start dropping wads of cash on them as described in the posts above. This takeaway is from owning dozens of Corvairs in many configurations. These two combos were the best, and most fun to drive per dollar. The 102 car was built using a combo of a $300 running 1964 car (with a 63 102 in it) and a basket case $400 1966 coupe for the trans swap and rear gear. Her OG car was a 110 PG, and was a pig on the highway.
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