Brent Hudgin
I'm New Here
I am building a Lancair 360 and wanted to post here about my engine in case there are others that are interested. I am working on turbo-normalizing my IO-375. I have had a lot of help from Ross Farnham at SDS, where I bought my EFII system. I am using two Honeywell-Garrett GT2252 car turbos with internal wastegate. I am going this route for cost considerations as well as fitting everything in the tight 360 cowling. Lancair built one turbo 360. I have talked to the guy that did it, and he advised that a dual turbo setup would be much easier. The turbos cost about $1,700, intercoolers about $800 and a new wastegate controller package no more than $1,500. There are some other costs such as making support brackets and the exhaust, but the entire system should stay under $5,000. I should be able to mount the turbos high enough that a scavenge oil pump will not be necessary.
There is a Lancair owner (Nidal at EngineBridge) that has done a number of electronic control devices which have improved the airplane. Nidal?s expertise will bring some very nice advances in turbo wastegate control. His controller will use servos to precisely match each turbos output to a pilot selected pressure. This avoids all of the oil plumbing, any exhaust crossover and in some airplanes a mechanical linkage that attempts to match the two. There will be a pressure sensor at each compressor outlet. The desired output will be selectable instead of a fixed value as in hydraulic controlled wastegates. This will allow the butterfly valve in the servo to stay fully open in cruise, while the pilot selects the desired turbo output. The wastegates are modulated to give that pressure until they are fully closed. If somebody wanted this to work just like their previous turbo aircraft, they could just set a value (say 32?) and leave it alone, using the throttle to set cruise power. With this system, the pilot can control warm up and cool down of the turbo.
I have been asked about complete electrical failure. My airplane will have multiple electrical backups since the engine will not run with a complete failure. In an aircraft where this isn?t the case, a complete failure would freeze the wastegates in whatever position they are in. If fully open, the engine is normally aspirated. Fully closed and max turbo output is available with power being controlled with the throttle. In between will give some turbocharging output.
This controller will also work for a single turbo and an aircraft wastegate.
I am still months away from running the engine. I anticipate beginning to fit the turbos and intercoolers later this month. The reason for posting now is to gauge interest in this controller and to see if anybody has suggestions for added features.
There is a Lancair owner (Nidal at EngineBridge) that has done a number of electronic control devices which have improved the airplane. Nidal?s expertise will bring some very nice advances in turbo wastegate control. His controller will use servos to precisely match each turbos output to a pilot selected pressure. This avoids all of the oil plumbing, any exhaust crossover and in some airplanes a mechanical linkage that attempts to match the two. There will be a pressure sensor at each compressor outlet. The desired output will be selectable instead of a fixed value as in hydraulic controlled wastegates. This will allow the butterfly valve in the servo to stay fully open in cruise, while the pilot selects the desired turbo output. The wastegates are modulated to give that pressure until they are fully closed. If somebody wanted this to work just like their previous turbo aircraft, they could just set a value (say 32?) and leave it alone, using the throttle to set cruise power. With this system, the pilot can control warm up and cool down of the turbo.
I have been asked about complete electrical failure. My airplane will have multiple electrical backups since the engine will not run with a complete failure. In an aircraft where this isn?t the case, a complete failure would freeze the wastegates in whatever position they are in. If fully open, the engine is normally aspirated. Fully closed and max turbo output is available with power being controlled with the throttle. In between will give some turbocharging output.
This controller will also work for a single turbo and an aircraft wastegate.
I am still months away from running the engine. I anticipate beginning to fit the turbos and intercoolers later this month. The reason for posting now is to gauge interest in this controller and to see if anybody has suggestions for added features.
