Carbon deposits

[meicalnissyen]

I am intensly curious in a philisophical way regarding the DI intake valve deposits seen by audi vdub, and us

here are my thoughts/goals

a shaky database of peeps who have actually seen their intake valves

separated by smoky turbo, and non
sub sep by catch can and non

pics and milage would be good

after seeing a pic of a f'd up motor with nasty deposits, except for a clean spot on the piston crown under the injector,..................... I gots real interested

 

[creedns]

catch can or not were all ******. i have 2 catch cans, my egr deleted and 2 pcv valves inline to the manifold and i still have gunky valves. welcome to the world of di bulls***

 

[FrequentFlyer]

There's really no way around it and unfortunately car manufacturers aren't doing much about it (other than maybe changing future designs). Most of it is on the responsibility of the owner and it comes out of your pocket to get it cleaned out, only to have it happen again over time. It doesn't take long either.

You can mitigate it by using a good synthetic oil (preferably a HD diesel blend like Rotella), do Seafoam treatments before every oil change, avoid long periods of idling, avoid stop and go traffic, avoid short trips that don't allow the car to come up to operating temps, etc... For some of us, most of these things aren't realistic. Unfortunately, without a borescope, it's hard to see what your valves actually look like. I can only assume the Seafoam is doing something, but I have a feeling it really isn't.

 

[shpankey]

I have a Catch Can and also have Devil's own Methanol kit to try to combat it, but trust me, they are very dirty anyhow and I can easily feel the loss in performance b/c of it. Thinking of an EGR delete next, but even then, it'll still happen. All we can do is slow it down.

 

[justanothermp5]

egr delete, catch can, and u should be good
the PCV and egr are really the only things that gunk up the valves correct?

 

[shpankey]

The Catch Can will unfortunately not catch it all however. Though PCV bypass to the exhaust using Venturi extractor. By the way, that is illegal.

wink wink

 

[meicalnissyen]

The Catch Can will unfortunately not catch it all however. Though PCV bypass to the exhaust using Venturi extractor. By the way, that is illegal.

wink wink

Venturi extractor in the exhuast

thats interesting, with a check valve in there somewhere I suspect.


Really, the only way the carbon can get to the valve is thru the PCV, and turbo seal. Unless I missed something.

Got pics of that setup ??

 

[Darth Vader]

BITD, some race engines that had low manifold vacuum and loose tolerances use extractor systems to keep crankcase pressure low, primarily to ease resistance on the recip assembly and raise power slightly. It's an idea but, it is totally not practical on a street car, hence the poster's "wink wink"(spin).

What engineers do now, with street engines, is design airflow passages in the engine's crankcase to reduce pumping losses like these. Lots of modern motorcycles have them, as they are expected to rev to 13k+.

 

[creedns]

yup, venturi to the exhaust is the best way to help alleviate the problem, but still wont fix it. and who cares about legalities lol no cats, no egr, all sorts of no no and no on my car hahaha