SPA Unveils Their 3.3L Corvair

By Anthony Liberatore

In a discussion with Rachel Weseman of Sport Performance Aircraft ... who is the wife of SPA's Founder Dan Weseman ... I asked "does Dan take vitamins?"

She said no. "I tried to get him to take them but he won't."

But Rachel said even without the vitamins, she is amazed at Dan's energy level, how focused he is, and how much he gets accomplished. In the last few years Dan has had a large number of accomplishments.

These include taking his Single Seat Panther aircraft from a dream to a flying aircraft and now deliverable kits with a number of customers close to test flight. It's 2 seat tandem Cousin the Cougar continues to be developed. On the Corvair Engine Conversion side of the business, Dan's signature "5th Bearing Kits, American made crankshaft from a billet, and all his other Corvair conversion products, are deliverables too. And if all that wasn't enough, Dan has another project that just ran on Tuesday, July 13th on a test stand at their Green Cove Springs, FL facility ... and will be displayed at their Booth in the north aircraft display area.

This project is a big bore and stroker kit (an additional 300cc's bring this variant up to 3300cc's) for the Corvair engine. This kit utilizes a stroker version of their US made forged Timken 4340 billet crankshaft, that added an additional 5/16" stroke and also incorporates 92mm forged / CNC machined aluminum Pistons, along with the standard Corvair conversion parts from William Wynne with FlyCorvair.com.

Helping to translate the power to the crank is a set of proprietary forged and CNC machined connecting rods utilizing technologies often seen in stroker applications such as ARP Bolts that secure the threaded lower end cap of the Connecting Rod without a nut and elegant radius on the cap end for rotating.

When I spoke to Dan about the 1st engine run, he said it ran smooth. Dan noted it fired right up and at after a 1/2 hr. they noticed a small leak on the 5th bearing line. It wasn't a major concern, but they did the prudent thing and shut her down to tightened up the leaky nut and fired it right back up. The engine then ran it for another 1/2 hr. Dan noted that when they get back for Oshkosh a serious testing program will ensue with a an interesting twist. Dan noted they have secured Dyno time at an independent Dynommeter facility and will run three engines and publish the dyno results on their website for the whole world to see.

This will include a 2700cc Corvair, (stock) the current 3000cc configuration and the new 3300cc engine. When I asked about potential horsepower of this 3300 variant, we had a discussion about horsepower in general and he noted one reason for publishing the Dyno results of all three engines will be to reflect reality, however he feels this 3300cc unit will probably come in around 115hp.

FMI: http://flywithspa.com/the-stroker-engine-is-here-see-video