Jump to content
SAU Community

Recommended Posts

Originally posted by DennisRB30

If you get rid of the PCV system your engine will build up harmfull acidic gases which contaminate the oil reducing engine life.

I just got rid of my PCV and vented it straight to the Atmosphere. Is this bad? or is it only bad when you block it of completely. I'm finding alot of oil and shite in the intake. Never really known about the PCV, lol.

  • Replies 153
  • Created
  • Last Reply

Top Posters In This Topic

You can remove the PCV valve(illegal) or block it so it looks operational, but you must have a catch can to filter out the blowby gas/oil otherwise it will get sucked up into the intake/turbo/intercooler/engine.

INASNT have you blocked off the PCV valve or not?

VPW mailorder, there in epping but deliver to your door and yes they come with brackets but there kinda crappy so im making better ones also i had to go buy some hose and some fittings but that cost me like $20, and the catch can was $90 soooo its all good alot cheap than the cusco ones

i've installed my cusco oil catch can good 9-10months ago, but i am yet to fill 1/2 of the can with oil ... is this normal? everything is connected correct got it checked by my mechanic when i was servicing my car last saturday... i've heard some stories like someone losing more than 1litre of engine oil on the track and stuff... i've been to 3 track days with the catch can installed and i didn't lose that rediculous amount of oil... is anything wrong here?

nissaner, theoretical part 2: Your catch can is stuffed and doesnt work:) j/k

If you take off the oil fill cap when at idle, you will soon know if you are getting much blow by - on cars with poor (compression) rings, you will notice air escaping at a fair rate - thats if the pcv valve isnt blocked:p

Guest INASNT
Originally posted by turbomad

You can remove the PCV valve(illegal) or block it so it looks operational, but you must have a catch can to filter out the blowby gas/oil otherwise it will get sucked up into the intake/turbo/intercooler/engine.

INASNT have you blocked off the PCV valve or not?

nope, it feeds back after the the catch can

About catch cans. I bought an AVO unit 'bout a year ago. It has two inlets on the top and one outlet on the side. I use it on my RB20.

I have blocked off one of the inlets, connecting the catch-can only to the exhaust-side cover. The exhaust-side cover is connected to the intake-side cover as normal, which is the connected the inlet plenum as normal.

The catch-can outlet is connected to the pipe between the AFM and turbo as normal.

I still find that I have heaps of oil in my intake pipes. I also noticed that there is never a real build up of oil in the catch can (should there be?).

Am I expecting to much (thinking this should leave no oil in my intake)? Should I connect it up differently? I'm asking coz I feel like I've wasted my money - but you guys rekon catch-cans are ok.

if you've still got the breathers connected to the plenum, then the catch can probably won't do much. You've given the air two paths to take, and going straight into the plenum is much easier than going through the filter in the catch can. So there probably isn't much air going into the catch can, thus the lack of oil. I think if you block off the line going into the plenum things may improve. Also make sure that the catch can actually contains some filtering material. Some of them rely on the assumption that you'll have one of thos cute little k&n's attached to the outlet to do all the filtering. If this is the case with yours, then without the little filter all you are doing is running the blow-by through a can, which won't do much at all.

Thanks Belly_up,

Once again for the people in the cheap seats - you reckon I should block off the line between the plenum and the intake-side rocker cover (I'd remove the valve and replace it with a brass plug).

I should then run one line from each of the rocker covers to the two inlets on the top of the catch can. I should then assess whether the can has filter material in it, if it does, I can plumb back to the inlet piping, if it doesn't I should put a filter in it.

Does that sound like what you mean?

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • For once a good news  It needed to be adjusted by that one nut and it is ok  At least something was easy But thank you very much for help. But a small issue is now(gearbox) that when the car is stationary you can hear "clinking" from gearbox so some of the bearing is 100% not that happy... It goes away once you push clutch so it is 100% gearbox. Just if you know...what that bearing could be? It sounding like "spun bearing" but it is louder.
    • Yeah, that's fine**. But the numbers you came up with are just wrong. Try it for yourself. Put in any voltage from the possible range and see what result you get. You get nonsense. ** When I say "fine", I mean, it's still shit. The very simple linear formula (slope & intercept) is shit for a sensor with a non-linear response. This is the curve, from your data above. Look at the CURVE! It's only really linear between about 30 and 90 °C. And if you used only that range to define a curve, it would be great. But you would go more and more wrong as you went to higher temps. And that is why the slope & intercept found when you use 50 and 150 as the end points is so bad halfway between those points. The real curve is a long way below the linear curve which just zips straight between the end points, like this one. You could probably use the same slope and a lower intercept, to move that straight line down, and spread the error out. But you would 5-10°C off in a lot of places. You'd need to say what temperature range you really wanted to be most right - say, 100 to 130, and plop the line closest to teh real curve in that region, which would make it quite wrong down at the lower temperatures. Let me just say that HPTuners are not being realistic in only allowing for a simple linear curve. 
    • I feel I should re-iterate. The above picture is the only option available in the software and the blurb from HP Tuners I quoted earlier is the only way to add data to it and that's the description they offer as to how to figure it out. The only fields available is the blank box after (Input/ ) and the box right before = Output. Those are the only numbers that can be entered.
    • No, your formula is arse backwards. Mine is totally different to yours, and is the one I said was bang on at 50 and 150. I'll put your data into Excel (actually it already is, chart it and fit a linear fit to it, aiming to make it evenly wrong across the whole span. But not now. Other things to do first.
    • God damnit. The only option I actually have in the software is the one that is screenshotted. I am glad that I at least got it right... for those two points. Would it actually change anything if I chose/used 80C and 120C as the two points instead? My brain wants to imagine the formula put into HPtuners would be the same equation, otherwise none of this makes sense to me, unless: 1) The formula you put into VCM Scanner/HPTuners is always linear 2) The two points/input pairs are only arbitrary to choose (as the documentation implies) IF the actual scaling of the sensor is linear. then 3) If the scaling is not linear, the two points you choose matter a great deal, because the formula will draw a line between those two points only.
×
×
  • Create New...