It kind of depends what area of ME you want to work in, but if it is at all related to design and manufacturing, get machine shop experience any way you can. Hands on experience will give you a huge advantage when it comes to designing parts for manufacturing.
If you have access to a machine...
Look for a club that interests you on campus, usually lots of interesting projects going on (robotics, race cars, electric cars, human powered submarines etc...). Sometimes they run through summer.
Arc second resolution is readily achievable with an external optical encoder, several companies make them, such as Renishaw: https://www.renishaw.com/en/atom-encoder-series--37564 (~$500?)
Even if you used a stepper, at least you could monitor the actual position not just commanded...
Lots of great bearing options have been listed already.
If you want to invest some time and money on the motion control side adding a rotary encoder, brushless motor and motion controller+motor drive, would do quite a bit to improve repeatability over a stepper.
There are probably lots of reasons why. Off the top of my head, higher efficiency due to higher compression, lower pumping losses due to no throttle in intake, diesel is safer and easier to store. I am no engine expert, just an ME who likes engines.
Gasoline self ignites just fine in a high compression diesel engine, way too quickly in fact, violently. "does not self ignite easily" makes no sense, maybe it means it is uncontrollable?
There are new gasoline engines working on using controlled autoignition google this "Controlled...
FYI, dry sump oil pumps achieve this effect. What kind of pumps are you using? Electric?Yes, you are on the right track, to pull any vacuum at all you need to be able to keep up with the blowby flow, to pull an actual vacuum, you need to "pull" many times more than the blowby flow.
Horsepower is horsepower, this is really more of a duty cycle question. For example the semi engine is designed to put out 400 HP mile after mile, day in day out. The Hemi gas motor is much ligher duty, only designed to put out the 400 HP for accelerating onto the freeway or a drag race. You...
Do you have a forcing mechanism with displacement sensor for the output? (e.g. shaker table?)
If not, a quick and dirty method is to excite the system with a known/repeatable forced displacement, then watch the ring down to calculate the fundamental frequency (counting peaks and calculating...