[KevM2]

Came across this video showing significant oil in the catch can:

Those of you who know more about the engineering of the S55 engine, what do you guys think about using a catch can? Some people suggest catch can will prevent proper lubrication to the upper engine/valves. Any thruth to this?

[S55bruh]

My guess is he broke in his motor the ultra easy way. Never getting throttle past 50% and never going over 3k rpm lol.

IMO break the engine in hard within first 20 miles. Lots of heat and lots of pressure. Gets the rings seated properly.

Just my 2 cents, however.

I’ll be adding a catch can very soon. I have 150 miles on the engine and I’ve been driving her hard. Once it’s installed I’ll snap some pics before I go for 1200 mile service.

[akkando]

The S55 has been around for a while. I feel the F80-82-83 owners would have this figured out already, so whatever they say is needed or not needed, go with that.

[ContactPatch]

What weight oil are you using, looks really thin, sounded like water when poured into the measuring cup?

[ONLYA6]

That's mostly condensation. Nothing to worry about. I removed the catch can on my N55 after collecting nothing but that for 40k miles. It would fill up in no time with condensation in the winter.

Catch cans are a good investment on N54s but the 55 motors have an improved system.

[mike@x-ph.com]

Its an upgrade worth having in my opinion

[Project_F87]

Yes that is 100% mostly condensation.

[chmura]

What catch can is he using in the video?

[doughboy]

It's a nasty toxic corrosive emulsion of oil mist/water/fuel and combustion by products. It has zero lubricating qualities.

Better in the can than spread all over your intake system and burnt onto your intake valve stems.

[Dynamic_m235]

Originally Posted by S55bruh

My guess is he broke in his motor the ultra easy way. Never getting throttle past 50% and never going over 3k rpm lol.

IMO break the engine in hard within first 20 miles. Lots of heat and lots of pressure. Gets the rings seated properly.

Just my 2 cents, however.

I'll be adding a catch can very soon. I have 150 miles on the engine and I've been driving her hard. Once it's installed I'll snap some pics before I go for 1200 mile service.

I was under the impression not to rip any car until 500 miles so everything breaks in. Are you sure it's not bad for your engine to rip it only 20 miles in?

[S55bruh]

Originally Posted by Dynamic_m235

I was under the impression not to rip any car until 500 miles so everything breaks in. Are you sure it's not bad for your engine to rip it only 20 miles in?

I actually started it when there was only 6 miles on the odometer after leaving the dealership lol.

And don’t misunderstand, I didn’t needlessly floor the gas as soon as I left the lot. I followed a steady, deliberate process that eventually worked up to limited sprints at WOT.

A member here suggested a particular method, which you can see here: https://f80.bimmerpost.com/forums/sh...&postcount=238

[Dynamic_m235]

Originally Posted by S55bruh

I actually started it when there was only 6 miles on the odometer after leaving the dealership lol.

And don’t misunderstand, I didn’t needlessly floor the gas as soon as I left the lot. I followed a steady, deliberate process that eventually worked up to limited sprints at WOT.

A member here suggested a particular method, which you can see here: https://f80.bimmerpost.com/forums/sh...;postcount=238

Cool I'll take a look thank you

[S55bruh]

Originally Posted by mike@x-ph.com

Its an upgrade worth having in my opinion

Scotty likes them, too. Lol.

Just got mine on. Shipped quickly from xtreme power house.

[mike@x-ph.com]

Originally Posted by S55bruh

Scotty likes them, too. Lol.

Just got mine on. Shipped quickly from xtreme power house.

[twintiga]

Is BMS the best option here? Is it a direct fit onto the M2c?

[S55bruh]

Originally Posted by twintiga

Is BMS the best option here? Is it a direct fit onto the M2c?

“Best” is a matter of opinion. There are others on the market with different features.

I just went with BMS product simply because it’s the most popular. It bolts directly to the frame.


http://www.burgertuning.com/instruct...tall_guide.pdf

[mike@x-ph.com]

Originally Posted by S55bruh

“Best” is a matter of opinion. There are others on the market with different features.

I just went with BMS product simply because it’s the most popular. It bolts directly to the frame.


http://www.burgertuning.com/instruct...tall_guide.pdf

Congrats

[KevM2]

Originally Posted by mike@x-ph.com

Congrats

The BMS one does not require removing any other components such as the CF brace (on the S55) and it's a super easy bolt on correct? I believe other ones like the Turner one is much more involved

[nomoracin]

So, if a catch can is so important, then why doesn't BMW just include one?

[KevM2]

Originally Posted by nomoracin

So, if a catch can is so important, then why doesn't BMW just include one?

Good question! I believe because that would mean admitting that the engines have a problem with carbon build up, and also, many interested buyers would be turned off from having to regularly empty the container.. not everyone is a petrolhead who loves to maintain their cars

[F87source]

Originally Posted by nomoracin

So, if a catch can is so important, then why doesn't BMW just include one?

Because non car enthusiasts may forget to empty them, then it's like have a full can of oil being sucked into the air intake tract which can cause more issues than slowly consuming the vapors.

The rumours about occs stopping valve lubrication is nonsense imo. The valves don't need to be lubricated by the crank case vapors, they only do that to prevent emissions issues as you can't dump oil into the environment. If anything it's worse to have carbon build up clogging up the valves without a catch can than to have a catch can and no oil there. Because the valve don't rub against other metals so it doesn't need to be lubricated.

[doughboy]

Originally Posted by nomoracin

So, if a catch can is so important, then why doesn't BMW just include one?

They do in a way - its in the cylinder head cover, cyclonic oil removal and drainage return.

It just doesn't work very well...

It gets plenty of the physical oil out of the gas stream, but not the oil vapours, mainly as the head cover is plastic and gets very hot the oil vapours don't condense so they carry on back to the intake tract / front turbo / intercooler / charge pipes / inlet manifold and condense in there instead!

A separate catch can will only catch oil mist ejected under boost conditions. Not when idling or on overun, in those cases a valve in the head cover opens and the crankcase is directly scavenged by the vacuum behind the throttle plate, so oil vapours are then sucked directly into the inlet manifold locally, bypassing any catch can etc.

There is nothing you can do to stop oil & carbon deposits getting on the valve stems and inlet tract during the idle or overun phases.

But (i'm fitting the BMS OCC) a OCC will reduce greatly the "on boost" oil vapours (of which the volume is much greater than idle vapours) and which cause the most mess going back through the turbo etc.