General boxer engine question...
 

Is it me or do boxer engines produce more steam through exhaust than twin and V engines during idle? Makes no difference if car is hot or cold.

Below is video courtesy of our beloved member @humfrz

Variables that come to mind after 18.4 seconds of consideration.
Size of engine
Humidity of ambient air
Temperature of ambient air
Engine operating temperature between starts.
Integrity of head gasket

I am suggesting too many variables to answer your question.

hmmmmm........I wouldn't think there would be any significant difference than with any other gasoline, fuel injected, engine with similar displacement and smog control devices.

Maybe it just looks that way to us, because we like to watch and listen to the exhaust when the engine starts up ..... :D


humfrz

Roger that. :thumbsup:

Peter that.

fify

Washed my pickup, then friends 2.5 RS and noticed his exhaust (all stock car) had clouds blowing out of its exhaust when we turned it on, so he asked me to turn on my FRS to compare and same thing! I have TRD exhaust.

Then neighbor's boyfriend came over and he has a SI so we checked his exhaust out and noticed our cars (Subaru's) shoot out/burn out more steam. Got me curious.

Temps on cars read 55-57 for outside. I'm sure that was also a factor, but my truck didnt have huge clouds.


p.s. his car has 65k miles all stock that he bought from older couple two years ago. He pampers that sob more than his mom. His car has zero issues and does not burn coolant nor oil AFAWK.

I think the important thing here, is to note that resident old man, @humfrz made a ricer exhaust video like a young buck.

Bravo good sir.

Horizontally opposed engines notoriously blow smoke at startup.


I have always assumed it was because oil pools on the side of the cylinder when the engine is not running.
This allows slightly more oil to pass the rings than a comparable straight or V configuration.


VWs and Porsches all do it to some extent.


If it is doing it long after startup then it is something else.

General boxer engine question...
 

I have the same problem.(don't know if this is normal) I would start up at 50 degrees and steam would come out, and continue to. Sometimes I would see water underneath my exhaust tips.


Sent from my iPhone using Tapatalk

water means your cats are working good and you are having efficient combustion

We gotta love @humfrz, he's a big child in an adult (o.g.) skin costume.


...wait that dont sound right.


@Jonathanlim,


Pumping gas from Chevron does that for me but not Arco or Shell. It probably has to do with mixes they put in there as well. My .02 cents are also on it being a Subaru thing. Will confirm later at work with a Legacy one of my co-workers drives.

General boxer engine question...
 

My guess is that they don't.. Id say a 4cyl 2.0 boxer makes about the same as any sort of inline 2.0 four. But hey who knows. I know my FR-S bellows a lot of steam on startup.
EDIT: for sure not a problem though. Looks like everyone is doing it

I wonder if its related to exhaust piping design? Our overpipe goes up a bit before coming back down to the midpipe right? Maybe all the water from cats and whatnot pool there after we shut off engine.