Opinions on 1962 Spyder was: Shades Classic

[66vairguy]

You asked what was "Turbo specific" on the Corvair engine.

In 1962 the connecting rods were "beefed up" on ALL the engines. The Turbo engines got nitrided crankshafts. In 1965 and later the 140HP engines also got the nitrided crankshaft. It is NOT stronger as many believe, just the bearing surfaces are harder to reduce wear. The hardening is shallow and if you "cut" a nitrided crankshaft 0.010" the hardening is removed. Stock pistons were used, although now it's recommended that an aftermarket forged piston be used in place of the stock cast piston.

The Turbo engines did have different heads with improved valves and guides.

In Corvair books I've read the experts say the Turbo boost was limited by the carburetor size and the turbo size - that's why Turbo Corvairs are slow to get to boost and most say you don't feel much boost until you get into third gear. The muffler is stated to NOT be a restrictive part of the Corvair turbo system and in fact has very low resistance.

If you want first gear stop light go then the carburetor engine is probably a better choice, on the highway the Turbo shines. BTW - ALL Corvairs, except the base engine cars, used premium fuel.

[bbodie52]

The engine shrouds were also cut differently, a special exhaust configuration was fitted, and the turbo heads had as lower compression ratio. The right head had a hole for the oil return line from the turbocharger. The distributor was unique, with a timing curve specifically designed for the turbocharged engine. There was no vacuum advance — just a similar device that RETARDED the ignition timing under boost (not necessarily reliably).

Premium fuel was specified for all Corvairs, but I have found that most normally-aspirated Corvairs will tolerate middle-grade or even Regular gas in cooler ambient temperatures, under light load conditions, etc. But on hot days or when the car is heavily loaded, or will be doing highway driving with lengthy uphill grades you may start to hear the engine ping (detonation). Such conditions are very destructive to the engine and cannot be tolerated. If you find you can normally run regular fuel in and around town, you can save some money. But plan on Premium fuel when you expect the Corvair to do some "heavy lifting".

The turbocharged Corvair usually gets the poorest fuel mileage, and MUST run high octane fuel at all times. A low compression ratio, high octane fuel, and the special distributor with pressure retard device are the only defense mechanisms that keep the turbocharged engine intact.

[8888]

Thanks for the detailed replies!