Quote:
Originally Posted by hyeprofile
Thanks. I was hoping that with the engine in the car the intake manifolds could be popped off enough to sneak a walnut blaster and shop vac in there. Guess not.
BTW how are those blocked off intake CCV ports working out? Any issues with rough idling? I'm thinking that Sophisticated Redneck 's suggestion to add a pressure-adjustable check valve (set at ~-8psi) from both intake CCV ports and running it into the catch can might not be a bad idea. Worse case I could always adjust that check valve to almost entirely closed, and just back it off if I get rough idling issues.
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Blocking them should'nt cause rough idle on the M as it doesn't use MAF sensors, the n63 that remains to be seen if it will as this is something that might have been allocated for on the airflow maps.
The key here is to try to get some negative back pressure into the crankcase. We can't go much over -8psi as air will start being pulled through the front main seal (sounds just like a slipping belt) which is a shame as there hidden horse power gains there. Not to mention less oil running down your valve stems means less carbon buildup and less oil dilution from crank case gases over time. Even at -5 to -8psi the effect on oil burning with engines that have worn valve stem seals is dramatic.
Trade off is you must have a proper catch can to filter the oil out of the air, oil has a dramatic effect on lowering octane, not so much a concern on stock engines, but slap on a tune that pushes the boost and it can become a real issue. Catch cans with built in sintered bronze micro-filters work the best.
Now that I am running a tune and soon a jb4 also, I want to take the CCV system to the next level. I will be installing Bernoulli tubes in the exhaust and completely blocking off the lower and upper intake ports to the CCV system.
I have no idea if this will work, there is very limited info on Bernoulli tubes on turbo charged cars with mufflers a s how much vacuum they can pull. Also how this will effect the air/file maps since I have the n63 as I mentioned before. There is only one way to find out...
If It pulls vacuum even with the exhaust flaps closed and doesn't make the exhaust smell any more unbearable with the downpipes then it already is, then this would be an excellent choice as it would greatly simplify the CCV system, especially on the M
Basically you will have the valve cover line run to a CCV can (don't want that oil in your exhaust pipes) then to the Bernoulli tubes (also called header evac systems) which incorporate a one way check valve) and that's it. Everything else is blocked off, no more combust gases or oil mist in the intake stream.
I have the kit and lines already to make the conversion, going to weld the tubes to exhaust clamps, this way you need to only crawl under truck and drill a hole in each pipe and install the tubes, no welding underneath. I have a vacuum gauge mounted inside the cab to monitor crank case vacuum. If it works I'll weld up some more sets for those interested. Installing this weekend and will post results. I'll do some draggy runs too see if any performance benefit not having combustion gasses in the intake and having vacuum in the crankcase....again assuming it works at all.