Turbocharging the I0-540 or oversized pistons

[a64pilot]

David,
I think the pop off valve is the waste gate. I wasn't accusing you of anything, just 55", I think is almost 30 PSIA boost. depending on compression ratio, that's a lot. For instance the P&W 1340 has a low compresion ratio of 7.3 to 1 but even with that low compression ratio the redline is 36"MP. Yes that is an OLD engine design.
I would think that sea level HP in a turbo normalized system could be 30" MP. Yes charge heating does come into play, but as you noted a good air to air aftercooler can help.
I wonder what the WWII big HP motors could pull without alcohol/water injection?

[210TC]

The waste gate is manual and allows the exhaust gases to be directed via a throttle butterfly to the turbo or out the exhaust (bypass). The butterfly works just like your carb butterfly. Fully closed (butterfly) all gases go to the turbo and vise-versa.
The pop off valve is a safety valve in the intake system. It can be adjusted while the cowl is off. It is to be set at max allowable pressure.
The TO360 is also 7:3 to 1

[210TC]

Normalized only maintains 29.92" to a certain altitude, then falls off.
Turbo normalizing is easy to get an approval because it does not increase the HP of the engine. It just HELPS the engine maintain sea level HP to much higher altitude.
Normal sea level pressure

[a64pilot]

Normalized only maintains 29.92" to a certain altitude, then falls off.
Turbo normalizing is easy to get an approval because it does not increase the HP of the engine. It just HELPS the engine maintain sea level HP to much higher altitude.
Normal sea level pressure

Bingo, but if I could carry sea level power to above 10,000, I'd be happy. Normalized also isn't as hard on an engine if it's done right.

[aero101]

Might be worth giving Tom Anderson at XP Mods at Arlington Airport in NW Washington a call. I have customer Cessna 170 here that he converted a Fuel Injected IO360 to a Turbo'd 360 on a one time STC. We did installation, test program, mostly on floats but works pretty good. I would think that he could tear down and convert a Fuel Injected 360 into turbo like he did on this one? On the M5, could probably be built on the original TCDS and not require the STC? Biggest change is compression ratio gets dropped and all the plumbing... This one makes about 210HP at 32" MP, has manual waste gate, when needed can bump it up to about 38" MP and makes about 230HP. Nice up in the mountain lakes!! He also changed crank dampners to allow for the installation of a long McCauley Prop which helped on floats considerably... He kind of specializes in the Cessna 170 conversions, but I would think he could do an engine for you?

XP Modifications
17403 Smokey Point Blvd., Arlington, WA 98223
360-653-9294 or 800-819-9270 Fax: 360-658-9796