Can Aluminum Rotors survive BOOST?! 1000 Miles Later…

he remembered his password

When ppl say the miata sounds like a lawnmower, thay ain't ever heard this thing 😂

That balancer could have been flexing the shaft causing that wear. Just look at how bad it made the whole vehicle shake. That had to be an enormous force on the shaft. I'd say to write this wear off due to that and start fresh.

I suggest once clearances are sorted to do some hard anodized or self lubricating coatings.

It's insane this thing didn't catastrophically explode or weld itself into a solid mass considering the broken balanceing shaft and completely wrong timing

Difference in expansion rates between the steel and aluminum maybe causing some of the issues?

the gumminess is the cause of low compression. excess heat caused the oil to gum up. apex seals were not able to seat properly because they were stuck from the gum.

That 1 rotor is cool and all... But it sounds like someone tryng to fart into a white claw can.

I wonder if the side wear was because the counter weight was off balance causing the rotor to wobble and rub the sides.

Rob. I've rebuilt hundreds of rotories and built race engines. I would machine some spacers to the exact dimension of the width of the rotor housing. Then assemble the engine without the rotor housing. Then rotate the engine assembly and measure all rotor tolerances while rotating the eccentric shaft this will give you a lot of information about the eccentric shaft and rotor. It looks like the rotor was oscillating from the wear marks and this would kill compression.

"This is the part where the video is either made or broken, aside from the entertainment part." I'm so happy you are someone who is a car enthusiast/maniac that wants to teach before you are an entertainer. Don't get me wrong your sense of humor always make it enjoyable or entertaining but I know the core fans are here because they want to learn first, laugh second.

On the Norton rotary engine the apex pin seal path on the alloy side walls were a molybdenum material surface, this worked wonderfully and increased the engine reliabilty and life span. I don't see this being used on your engines?

Something like this but carbureted and on a go-kart would be insanity and it would be so reliable as an N/A rotary

Could the weird behavior of the rotor be due to the higher coefficient of expansion of aluminum compared to steel?

That wiped area is where the aluminum is getting hot and expanding faster than the steel around it and its binding slightly. i say this because its on the trailing side where the flame is going to be the longest. and more heat is going to build up causing un-even thermal expansion. may just have to warm the car up more or heat the oil before you start it to keep the steel and aluminum from being too different in heat

Rob Dahm, the science guy!

Aluminum expansion rate is my bet.

I wonder if the apex seals need a little more clearance in their slot. The rotor might be pinching the seal once the aluminum gets to operating temperature. I am guessing it is expanding incrementally more than the standard rotor on the outside surface of the Dorito. If I had the means, I would try heating the aluminum rotor with the apex seals inserted to operating temperature to check for clearance to make sure it can move. The pattern on the rotor face reminds me of ring-wash in a piston engine.

i could feel an upload tingling in the back of my brain

Job well done! Your analysis and dissemination of information is very thorough and thoughtful