robmar Posted January 30, 2006 Share Posted January 30, 2006 ok so I dooooo want to block of the breathers from my k series head to the plenum 🤔 so fumes are not sucked back into the engine... so the question is what do i block them off with 🤔 or do they in fact need to vent to air and not be blocked off car is a 1600K, CC dry sump, and DVA head running on standard SS ECU rob My MSN Space and Blog - Syndicate Using RSS Link to comment Share on other sites More sharing options...
oilyhands Posted January 30, 2006 Share Posted January 30, 2006 I'll block them for you Rob. Oily Link to comment Share on other sites More sharing options...
robmar Posted January 30, 2006 Author Share Posted January 30, 2006 supa just add it to the bill 😬 Link to comment Share on other sites More sharing options...
Peter Carmichael Posted January 30, 2006 Share Posted January 30, 2006 Those breathers will now (dry sumped) only draw air into the head/crankcase. There is no issue of fumes getting into the inlet charge. All the fumes go out via the venting from the dry sump tank via the catch tank. Option A is to pipe the dry sump tank vent back to the breathers so that the fumes generally circulate. Option B is to leave connected to the plenum, which will result in greater exhalation at the catch tank (sensible with VP2 big end shells as reduces acid condensate inside the engine, but you probably won't have these) Option C is to seal which is stoopid, but people seem to get away with it. Link to comment Share on other sites More sharing options...
robmar Posted January 30, 2006 Author Share Posted January 30, 2006 Peter - ok interesting points why do you want the fumes to circulate (optiona), is it not a good thing to get them (the fumes) out of the system. i currently have the standard plenum dry sump setup where it breathes from the dry sump tower to a catch tank (quite heavily) adn has the pipes fromt he head to the plenum... as oily has built the engine and he is happy to block them off then I am happy to be stoopid, unless you can convince me otherwise, and not too technical/scientific please... My MSN Space and Blog - Syndicate Using RSS Link to comment Share on other sites More sharing options...
Adrian Williams Posted January 30, 2006 Share Posted January 30, 2006 Peter with option A are you suggesting the D/S tank vents into the cam cover and not via it's own catch tank 🤔 Adrian Link to comment Share on other sites More sharing options...
robmar Posted January 30, 2006 Author Share Posted January 30, 2006 thats how I read it Link to comment Share on other sites More sharing options...
Adrian Williams Posted January 30, 2006 Share Posted January 30, 2006 Me too, shame I've drilled some holes for the catch tank isn't it ☹️ Adrian Link to comment Share on other sites More sharing options...
Peter Carmichael Posted January 30, 2006 Share Posted January 30, 2006 No no no.... The dry sump must vent to atmosphere via a catch tank; the blowby gasses have to exit the system somewhere. The dry sump tank is vented, so is at ambient atmospheric pressure. Option A describes an additional bit of pipework that links the crankcase and head back to the dry sump tank at ambient atmospheric pressure. Link to comment Share on other sites More sharing options...
Peter Carmichael Posted January 30, 2006 Share Posted January 30, 2006 Rob, you have option B at present. In my description I explain that this will result in lots of exhalation through the catch tank. If you go to option A, exhalation through the catch tank will be reduced and the engine will not be totally sealed. This will keep your seals working as they were designed and will also make the scavenge pump more consistently effective. Link to comment Share on other sites More sharing options...
Adrian Williams Posted January 30, 2006 Share Posted January 30, 2006 Now it all makes sense. Thanks Peter Adrian Link to comment Share on other sites More sharing options...
robmar Posted January 30, 2006 Author Share Posted January 30, 2006 so let me see if I understand 1. what I have now is that air is being sucked through the breathers into the head/crankcase via the plenum 2. if I move them (the breathers) to go to the catch tank they will suck air from the catch tank instead, 3. so i am guessing what is happening is that as gases are being chucked into the catch tank from the top of the bell tank they are then sucked backed into the engine via the head / crankcase breather of course the catch tank has a breather of some sort and some gases will be expelled via that rob My MSN Space and Blog - Syndicate Using RSS Link to comment Share on other sites More sharing options...
Adrian Williams Posted January 30, 2006 Share Posted January 30, 2006 Rob as I understand it the second pipe from the catch tank to the cam cover will reduce the vacuum in the crankcase caused by the scavenge pump. This gives the seals an easier life and stops the bell housing tank breathing so heavily. No doubt Peter will be along in a second to point out I'm talking out my 🙆🏻 😬 😬 Adrian Link to comment Share on other sites More sharing options...
robmar Posted January 30, 2006 Author Share Posted January 30, 2006 ok - I follow that, and i am guessing what is being said is that it is better to gives the seals an easier life and stops the bell housing tank breathing so heavily. versus getting any potential fumes going back into system rob Link to comment Share on other sites More sharing options...
Peter Carmichael Posted January 30, 2006 Share Posted January 30, 2006 the second pipe from the catch tank to the cam cover will reduce the vacuum in the crankcase caused by the scavenge pump Option A and B try to maintain ambient atmospheric pressure in the crankcase, exactly the same as the engine's original wet sump design. Option C will establish a partial vacuum in the crankcase. Some people (including Neil at Pace) think this is inherently good, but they miss out on some very important considerations This [options A and B] gives the seals an easier life Options A and C: stop the bell housing tank breathing so heavily. Only option A solves the heavy breathing issue and is good for the seals... without going into why option C is stoopid. Link to comment Share on other sites More sharing options...
Peter Carmichael Posted January 30, 2006 Share Posted January 30, 2006 versus getting any potential fumes going back into system The fumes will potentially condense out in the catch tank. It only really matters if you have bearing materials that are susceptible to acid attack, such as Vandervell VP2. Link to comment Share on other sites More sharing options...
robmar Posted January 30, 2006 Author Share Posted January 30, 2006 ok - oily hold off on that blocking up !!!! Link to comment Share on other sites More sharing options...
Peter Carmichael Posted January 30, 2006 Share Posted January 30, 2006 You will still need to block the pipes into the plenum. Link to comment Share on other sites More sharing options...
Rob Walker Posted January 30, 2006 Share Posted January 30, 2006 CC/Minister , pace and titan all advise that the engine be run sealed, helps reduce windage.de-aeriation of the oil and scavenge. I have thought long and hard on the issues with seals getting a hard time and concluded that they in fact get an easier life as the partial vacuum works in opposition to the spring tension within the seal that keeps the seal in contact with the spinning shafts. I have run my k sealed for years without any issues with seal failures. Your choice but I wouldnt call it STUPID Peter. Edited by - Rob Walker on 30 Jan 2006 14:35:31 Link to comment Share on other sites More sharing options...
Tony C Posted January 30, 2006 Share Posted January 30, 2006 With a Pace dry sump: on the advice of Neil at Pace and Matt at Think, I too run with both the cam cover ports blanked off. One sucks and one blows with the engine running. I have no problem with excessive breathing or seal leakage. Occasionally the engine "Clucks" - from where is a mystery 😬 BRG Brooklands SV 😬 It seems that perfection is achieved not when there is nothing more to add, but when there is nothing more to take away. (Antoine de Saint-Exupery) Link to comment Share on other sites More sharing options...
Peter Carmichael Posted January 30, 2006 Share Posted January 30, 2006 Hi Rob (Walker), The "stoopid" comment comes from certain individuals (who should know better) expecting a pump to suck even in a total vacuum. Over the years I have found proponents of "sealed" systems are very quick to assert benefits but have less than concrete evidence to back up the assertions. In the meantime I have been making assertions of my own. Tony, One sucks and one blows with the engine running. Not on a dry-sumped system. Both should suck. The clucking is unfiltered air being drawn past the seals into the engine. Albeit that my engine is highly modified in ways that affect the oil drainage, the problems of running sealed were visible on data logs when using my car on track. The issues appeared at 7900rpm. FItting a filtered breather to the cylinder head solved all the scavenge issues and allowed the engine to be used at up to 9700rpm under power with no oil issues. As my engine uses Vandervell VP2 bearings, it was appropriate to keep a through flow of clean air with the resulting Link to comment Share on other sites More sharing options...
david nelson Posted January 30, 2006 Share Posted January 30, 2006 Rob I would block of the hole thats 52mm in diameter, take the air filter off and put a sock or somthing in it. This will help. 😬 David SL #146 Link to comment Share on other sites More sharing options...
robmar Posted January 30, 2006 Author Share Posted January 30, 2006 David - thankyou for that suggestion 😬 and like most of your suggestions I will ignore it 😬 Link to comment Share on other sites More sharing options...
Rob Walker Posted January 30, 2006 Share Posted January 30, 2006 Hi Peter, I do not agree with your notion that the clucking is unfiltered air being drawn past the seals. The clucking occurs on a hot engine at idle/low revs when the scavenge pumps capacity to remove oil from the sump pan exceeds that being delivered into the engine by the internal oil pressure pump thus it drawings a mixure of air & oil and makes a funny sound " similar to trying to suck every drop of drink out of a glass with a straw. Rob Link to comment Share on other sites More sharing options...
Peter Carmichael Posted January 30, 2006 Share Posted January 30, 2006 RW, You could be right, but isn't this:when the scavenge pumps capacity to remove oil from the sump pan exceeds that being delivered into the engine by the internal oil pressure pump ... true all the time with a dry sump system? Isn't that the point? Why does the cluck happen only at hot idle? Link to comment Share on other sites More sharing options...
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