Mayolives Posted April 15, 2005 Share Posted April 15, 2005 I am nearing the completion of an F54, big turbo buildup with lots of goodies that will be installed in a road course car. Will I experience any pcv system, "oil dumping into the intake system", problems that my 90TT VG30DETT engine has always been plagued with on track? Should I eliminate the pcv system and or plumb a catch can into the system? The VG engine dumps oil in hard right hand corners and blows smoke big time. If I'm going to experience similar problems with the L6 turbo set up, I would like to address it prior to installing the engine. Quote Link to comment Share on other sites More sharing options...
GrayZee Posted April 15, 2005 Share Posted April 15, 2005 You have to either hook up the PCV or install a catch can. Quote Link to comment Share on other sites More sharing options...
randy 77zt Posted April 15, 2005 Share Posted April 15, 2005 with stock 81zxt in my 77 i have had no ontrack pcv problems with system routed as stock.i am installing megasquirt and i am putting 1 of those little k&n filters on the valve cover .i got a 78 pcv hose (zxt not available from dealer) and cut it down for bottem pcv hose.if that breather filter leaks oil i will route it to a puke tank. Quote Link to comment Share on other sites More sharing options...
Tony D Posted April 16, 2005 Share Posted April 16, 2005 Jeff Priddy was experiencing some oil in the intake tract, but was a function of the T/B he used and incomplete separation on the in-block screen. Most people don't have a problem, but go from full on boost blowby at 30psi, to full vacuum of almost 30"Hg on snap-throttle closures and you tend toget the idea that something will get sucked in eventually. So what Jeff did was to 1) Install a separation tank on the PCV 2) replace the stock PCV with a TRUE Check Valve 3) Make another baffle in front of the stock baffle inside the block to keep oil from being slung into the stock separator 4) Installed a restrictor orifice in the PCV line to limit how much vacuum can ultimately be applied. I have seen the restrictor used before on ITB setups. Herve Oluette on his TWM Triple TEC2 Injected N/A 3.0L engine used a .063" orifice in the block, running straight to his idle air manifold log for a PCV system. This kept his oil sucking to a minimum using Individual Throttles---probably the most severe service for oil sucking available. Any combination of the above items can be combined IF you run into a problem. There is nothing that can't be overcome... Quote Link to comment Share on other sites More sharing options...
Guest bastaad525 Posted April 16, 2005 Share Posted April 16, 2005 Jeff Priddy was experiencing some oil in the intake tract' date=' but was a function of the T/B he used and incomplete separation on the in-block screen. Most people don't have a problem, but go from full on boost blowby at 30psi, to full vacuum of almost 30"Hg on snap-throttle closures and you tend toget the idea that something will get sucked in eventually. So what Jeff did was to 1) Install a separation tank on the PCV 2) replace the stock PCV with a TRUE Check Valve 3) Make another baffle in front of the stock baffle inside the block to keep oil from being slung into the stock separator 4) Installed a restrictor orifice in the PCV line to limit how much vacuum can ultimately be applied. I have seen the restrictor used before on ITB setups. Herve Oluette on his TWM Triple TEC2 Injected N/A 3.0L engine used a .063" orifice in the block, running straight to his idle air manifold log for a PCV system. This kept his oil sucking to a minimum using Individual Throttles---probably the most severe service for oil sucking available. Any combination of the above items can be combined IF you run into a problem. There is nothing that can't be overcome...[/quote'] Holy jeez... that's a lot of trouble to go thru to keep oil outta the intake I dont run a PCV on my L28, I just run open breathers, but my Sentra I have to leave it all stock of course for emissions, and it has a HUGE problem with buildup from the PCV and EGR... sux to think I'd have to go to such great measures to get rid of it Quote Link to comment Share on other sites More sharing options...
Afshin Posted April 16, 2005 Share Posted April 16, 2005 I run the stock PCV system with 15 psi on open road tracks with no hint of a problem yet. I rebuilt my head 2 years ago so valve seals..are in good condidtion which probably helps. Quote Link to comment Share on other sites More sharing options...
Tony D Posted April 17, 2005 Share Posted April 17, 2005 I run the stock PCV system with 15 psi on open road tracks with no hint of a problem yet. I rebuilt my head 2 years ago so valve seals..are in good condidtion which probably helps. 15psi is about half of what Jeff is running. Even with good piston ring seals, there will be some blowby---the key is to minimize any oil migration whatsoever. After several tens of thousands of miles, when deciding to turn the wick up, Jeff decided he wanted to make ABSOLUTELY there was NO chance of getting any oil in there! One good surge on the compressor, and a wiping out of the carbon seal ring in the turbo, and everything on the PCV end of it is all for naught anyway... Once oil gets into the stream on boost, and detonation that will result is baaaaaad! The L-Series sealing is FAR supreior to the problem with a Z32. The Z32's are notorious for it, and I understand his concern, I was just letting him know the maximum legnths to go through if he's really concerned. This keeps a functioning PCV system, and really, with an EGR attached, Jeff's car could pass smog... Not many 500HP Turbo L-28's out there that could pass both a visual AND functional test in the state of California... Quote Link to comment Share on other sites More sharing options...
Mayolives Posted April 17, 2005 Author Share Posted April 17, 2005 Tony D, You are correct about the severity of the problem with the Z32 and the potential for detonation disaster. Doing all of the preventive measures to protect a high dollar engine would not be, IMHO, an over kill if they helped to prevent a bigger problem. I will call it cheep insurance. Thanks for the good advice. Quote Link to comment Share on other sites More sharing options...
Drax240z Posted April 17, 2005 Share Posted April 17, 2005 Well I went with the K&N breather method a while ago and am not liking it at all on my 82 turbo engine. I end up with oil on my valve cover all the time. I don't mind spending the money to get this system right though. Right now I have some mild detonation issues, and I am burning some oil under high vacuum cruising down hills. This has been the case on essentially 2 different engines I've used with the same PCV setup, so I'm thinking now that it's the PCV system or the turbo. I know quite some time ago Tim posted up his L6turbo PCV system, but those that have built a PCV system that flat out works, post it up! Aftermarket PCV valves are useless, has anyone found a check valve that they would recommend? Quote Link to comment Share on other sites More sharing options...
Afshin Posted April 17, 2005 Share Posted April 17, 2005 Originally posted by TonyD 15psi is about half of what Jeff is running. Even with good piston ring seals, there will be some blowby---the key is to minimize any oil migration whatsoever. I don’t believe that I was referring to Jeff’s car in any way whatsoever. I simply stated that with my set up, I have had no noteworthy problems to date, no more no less. I also have not implied that the stock set up could or should not be improved. I have thought about using a catch can myself, and certainly would modify it if I where to run 30psi. My point is that with 15-17 psi on a healthy stock engine (my car burns no oil) you can maintain a reliable and competitive car for non-professional level open road track events. I may very well modify my PCV system at some point, it’s just not on my priority list, but it is on my extensively never ending wish list (I have no significant oil build up in intake track, even after extended and hard use on the track…). As we all know, there is no end to reasonable enhancements that can be made to these cars, which is clearly demonstrable by my credit card bills However, I don’t see a healthy l28et having enough blowby at 15-17 psi level to cause detonation and damage the engine (many many of us have been running under 20 psi with stock pcv systems over many years). So my 2cents is that for non jeffP extreme set ups stock pcv will NOT cause engine failure…. Sure the system can be improved, but that is far from having to do it as the many other things one would have to do prior to having a reliable track worthy car. So the direct answer to the initial question is: No you will not experience the same problems as with the VG30DETT engine. BTW can you tell us a little more about your set up, 17 vs. 30psi goal, turbo, fuel system..… Quote Link to comment Share on other sites More sharing options...
510six Posted April 17, 2005 Share Posted April 17, 2005 In my turbo car a aircraft style air/oil seperator is used via the vent on the valve cover.The stock pvc system is retained.The oil seperatoe does have a vent outside the engine compartment for residual fumes.Works great. Quote Link to comment Share on other sites More sharing options...
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