Night Run: Carb and Intake testing


A quick look at Sunday night, outside my hangar. Dan Weseman was looking for an intake design and a Carb orientation and model, specifically for Corvair powered Panthers with tricycle gear. Tonight was the test run, and it turned out amazingly good.



Above, a look at the back of my test stand; Notice it is now sporting two lab grade 5 wire O2 driven Air/Fuel meters.  The test question was essentially this: If a Rotec TBI is turned 90 decrees, will it still have excellent mixture distribution to both sides of the engine. The answer is yes. This was the largest spread under power, .3 on the air/fuel ration. That is as good as carbureted engines get.



Above, Dan runs the controls.



Above, a look at the Rotec on the manifold. It started and ran exceptionally well.


After tests, Dan Rachel and I ate dinner at their place and talked about a lot of stuff, ranging from airport business to the new “Ford vs Ferrari” movie. It was a real nice end to a productive weekend.


For more info on carbs, look at this: Corvair Carb Reference page for 2020.




About William Wynne
I have been continuously building, testing and flying Corvair engines since 1989. Information, parts and components that we developed and tested are now flying on several hundred Corvair powered aircraft. I earned a Bachelor of Science in Professional Aeronautics and an A&P license from Embry-Riddle Aeronautical University, and have a proven 20 year track record of effectively teaching homebuilders how to create and fly their own Corvair powered planes. Much of this is chronicled at and in more than 50 magazine articles.

7 Responses to Night Run: Carb and Intake testing

  1. Why the Rotec when Ellison is made in the USA? Well… some may debate the idea that California is still part of the USA.

    • Read my other stories about Rotec carbs, the latest generation have 2 fine advantages over Ellisons. The host of Corvair College #36 owns Ellison today, we are friends, and that allows me to say with some degree of accuracy that their availability fluctuates. Rotec’s are available and work. If someone wants purely made in US in their cowl they can use an MA3 or an Ellison. It’s debatable if California or Australia is more repressive to individual liberty, so Ellison or Rotec, you’re inadvertently supporting repressive regimes.

  2. David says:

    Would you say that the MA3SPA is always going to be the best value for the money William? Or would you pin that to the mission of the aircraft?

  3. David says:

    And from what Ive heard about the rotec radial engines I hope their carbs are much better.

    • think of all the stupid things people say about Corvairs and consider that there is probably nothing wrong with their engines. Their carbs work perfectly so I’m putting money on the idea the engines are good also.

  4. rickifly says:

    Thank you for this conclusive test run of the cantilevered intake and Rotec TBI for the SPA Panther LS-TG. Very excited to use this solution for my 3.3L build. Dan installed a MAF bung on the intake also for me. Purchased the Rotec MK.II-34-2 series. Getting the CI monster ready for a break in run. well, Back to building…

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