Opening Puma Cases for Dirty Valves

Originally Posted by anE934fun

Am I missing something?

Yes: You still need to keep the injectors clean.

Originally Posted by Zeichen311

Yes: You still need to keep the injectors clean.

But all of the ads from gasoline distributors (Chevron for example) talk about their high detergent gas cleaning valves of fouling.

Injectors aren't subjected to blowback fumes like intake valves are. My understanding of the carbonized intake tract issue is that it is caused by blowback fumes.

I am not trying to be pedantic; just trying to understand what appears to be two separate issues. With non- D.I. engines, high detergent gasoline definitely stops intake valve fouling. But D.I. engines don't expose the intake valves to the detergent in the gas. Although some engines (Audi sems more susceptible than BMW, but that is just a gess on my part) seem more susceptible to carbonized intake tract than others. It gets curiouser and curiouser.

Originally Posted by Zeichen311

Yes: You still need to keep the injectors clean.

although im not sure if the formation of deposits is the same on a high pressure piezo injector-- i have not heard of any clogged piezo injectors, between the pressure and the environment, i have a strong feeling that the detergent in the gas has a negligible effect on keeping the injectors clean. i could be wrong though, havent looked into it much.

Originally Posted by Orient330iNYC

although im not sure if the formation of deposits is the same on a high pressure piezo injector-- i have not heard of any clogged piezo injectors, between the pressure and the environment, i have a strong feeling that the detergent in the gas has a negligible effect on keeping the injectors clean.

Which comes back to my original question about the benefit of using high detergent gas in D.I. engines....

Originally Posted by anE934fun

Which comes back to my original question about the benefit of using high detergent gas in D.I. engines....

marketing? old habits dying hard?

shell's marketing is sneaky, they dont come out and say it cleans DI, its implied

Is Shell V-Power Premium Gasoline safe for all vehicles?

Shell V-Power is effective in all gasoline-powered engines found in conventional, modern and hybrid vehicles as well as motorcycles, snowmobiles, and leisure marine vehicles.
Tested in today’s advanced turbo-charged and direct injection engines, Shell V-Power helps resist thermal breakdown at high temperatures, actively protecting against gunk under tough engine conditions.

Jumping into the Way Back Machine....back when carburetors were King, you definitely had carbon fouling in the combustion chambers proper (i.e. piston tops). With multi-port fuel injection that was reduced.
I don't know if DI completely eliminates dirty pistons.....

Originally Posted by Orient330iNYC

marketing? old habits dying hard?

shell's marketing is sneaky, they dont come out and say it cleans DI, its implied

Is Shell V-Power Premium Gasoline safe for all vehicles?

Shell V-Power is effective in all gasoline-powered engines found in conventional, modern and hybrid vehicles as well as motorcycles, snowmobiles, and leisure marine vehicles.
Tested in today’s advanced turbo-charged and direct injection engines, Shell V-Power helps resist thermal breakdown at high temperatures, actively protecting against gunk under tough engine conditions.

I totally 'hear' you. If you extend your example to Chevron gas, does the absence of the V-Power additive in Chevron gas mean that owners of turbo-charged D.I. engines that run Chevron gas are doomed to carbonized intake tracts? I doubt it. And to date, I haven't seen a gas distributor run a comparison test advert that compares their gas vs. a non-branded gas on intake carbonization in turbo-charged D.I. engines. I wonder why no comparo ads?

Originally Posted by anE934fun

Injectors aren't subjected to blowback fumes like intake valves are. My understanding of the carbonized intake tract issue is that it is caused by blowback fumes.

If you mean PCV exhaust, definitely.

I want a cooled catch-can w/crankcase return.

Am I asking too much?

Originally Posted by galahad05

Jumping into the Way Back Machine....back when carburetors were King, you definitely had carbon fouling in the combustion chambers proper (i.e. piston tops). With multi-port fuel injection that was reduced.
I don't know if DI completely eliminates dirty pistons.....

I suspect the carbon fouling in carbureted engines was due more to reduced fuel metering precision of the carburetor compared to fuel injection.

Originally Posted by CALWATERBOY

If you mean PCV exhaust, definitely.

I want a cooled catch-can w/crankcase return.

Am I asking too much?

Attachment 344566

Maybe in the engine that powers the replacement to the F30 cars? Although by then, BMW may have moved on to fuel cell power.

Originally Posted by anE934fun

Maybe in the engine that powers the replacement to the F30 cars? Although by then, BMW may have moved on to fuel cell power.

Interim solution:

Elastic intake valve alloy enables piston slap vibratory shock, fracturing carbon structures to fines requiring an electron microscope to resolve, coke becomes fuel.

Wascally huns!