two vs four stroke

The old Detroits were 2 stroke with a supercharger (Rootes type, just like the ones on the funny cars and fuellys). The rest are all 4 stroke.

 

detroits cant hold a seal.I love em but they shoot oil like a sprinkler. Not really lmao! uh oily motors tho. Straight pipe detroits sound the best.

 

Everyone calls 2 stroke Detroits leakers.

However they had drains in the block that cleared oil sitting in the bottom of the transfer port passages that spit oil. Sort of a built in leak....

The blowers used on early drag cars came off the Detroit 2 stroke diesels, the blowers used today at the drags are based on that design but highly improved.

 

You don't see the ole screamin jimmys anymore for pollution reasons. I thought it was just BS about running one backwards until I saw it one day. We had an old Detroit dump and the driver was in sand and almost stalled it out when smoke came blowing out from the air cleaner and it was knocking like crazy. I don't remember how he shut it off but I do know it was no big deal and he just restarted the engine and was on the go again.

They were fun on the job site. A driver would stop for a break and we would go and pull the emergency shut down and push it back in. He'd come out from his break and try to start the truck. He'd crank and crank until he'd see us on the ground laughing.

 

Remember when they "improved" them by adding a turbo? Imagine this.... blown turbo seal starts pulling oil from the base and putting it into the intake. Perpetual motion machine...... until it goes bang.

 

Navistar plans to use the opposed-piston engine being developed by EcoMotors. In some ways, it is the new two-stroke, but uses the layout that was in an airplane in the 1930s. The British railway also had opposed-piston diesels.

http://www.ecomotors.com/ecomotors-...r-engine-promises-revolutionize-commercial-ve

Another cartoon.

http://www.youtube.com/watch?v=buX89nlww2E

 

I use to drive an old Mack that would run backwards if you almost stalled it.
Happened a few times to me when pulling out of the pit with a really heavy load.
Darn truck and engine were over 20 years old at that point. And I still would hit the scale at the plant weighing 95k all day long.

 

There's also a design for a new type of engine that fires on all strokes. It fires on the way up then fires when it hits bottom.

 

Hence the emergency shutdown Gashauler mentioned, it was a trapdoor in the intake to stop airflow.