IHADAV8.com - Turbo Buick Tech, and Nonsense

Tech Area => General Buick Tech => Topic started by: Tim Hensley on April 24 2013, 03:14:14 AM

Title: cath can
Post by: Tim Hensley on April 24 2013, 03:14:14 AM
is one needed I hit the search nothing on this sight.
Like to have some input
I like the Mazda Speed  Corkspeed canhttp://www.corksport.com/corksport-oil-catch-can.html
thanks
Title: Re: catch cans
Post by: 1KWIKSIX on April 24 2013, 06:32:56 AM
Here's a couple of links from the other place.


Myself, I'm running a pair of AMW Catch Cans, 1 for PCV system &  for valve covers.




http://turbobuick.com/forums/threads/anyone-running-an-oil-catch-can-system.329436/#post-2596978 (http://turbobuick.com/forums/threads/anyone-running-an-oil-catch-can-system.329436/#post-2596978)


http://turbobuick.com/forums/threads/oil-catch-can-setup.377697/#post-3022968 (http://turbobuick.com/forums/threads/oil-catch-can-setup.377697/#post-3022968)


http://turbobuick.com/forums/threads/installed-an-oil-catch-can-today.392886/#post-3182417 (http://turbobuick.com/forums/threads/installed-an-oil-catch-can-today.392886/#post-3182417)


http://turbobuick.com/forums/threads/valve-cover-breathers.387760/#post-3125632 (http://turbobuick.com/forums/threads/valve-cover-breathers.387760/#post-3125632)


Title: Re: cath can
Post by: $1987 GN$ on April 24 2013, 06:53:22 AM
Not on a typical dd.

If it is a race engine; different story.


AJ___
Title: Re: cath can
Post by: motorhead on April 24 2013, 04:37:26 PM
http://www.ihadav8.com/forum/index.php?topic=2478.msg54721#msg54721 (http://www.ihadav8.com/forum/index.php?topic=2478.msg54721#msg54721)
Title: Re: cath can
Post by: tb3 on April 24 2013, 07:38:01 PM
I was interested in them at one time. 
I never installed one.
I guess whether one deems one is nesecery or not for their appliation, they can't hurt anything, correct?
 
Title: Re: cath can
Post by: Scoobum on April 24 2013, 07:42:42 PM
A catch can is a band aid for a deeper problem.
Title: Re: cath can
Post by: Tim Hensley on April 25 2013, 02:33:48 AM
Its not a DD
I mostly drive it to the race track and occasional Sunday drive
Engine is fresh, Iv been running 12 flat with a few 11.90 ,@25 psi got a new rotating ass.from DLS going to try to get it low 11s
I see no need to go overboard if not needed ,it has a check valve in the PVC,just trying to keep boost out of the crank case and unwonted oil out of the intake
I have seen a few post on this subject that made me look at the catch can as a good option
Members on the board tend to be a little more conservative,and i like to balance the opinions of both (Im keeping my oil cooler)
At 11.0s its not really a race car but I do race it a lot
I have not ruled a catch can out yet but starting to see it my be a over kill Thanks
Title: Re: cath can
Post by: Scoobum on April 25 2013, 04:45:49 PM
I bracket race my car most weekends spring to fall. I have it dialed in to run 7.1 in the Sportsman class. I never have a drop of oil from the breathers. I was out practising last Sunday and pounded 28 PSI through it...and the breathers were dry. I run an RJC valve in place of the PCV. Some have said their BLM's go through the roof with the RJC valve...but my BLM's are 128.
Title: Re: cath can
Post by: Tim Hensley on April 26 2013, 03:28:39 AM
  Those are the new numbers im shooting at
what breathers do you run ,I have a new set of TA covers
And is the RJC valve a check valve inline with the PVC
Title: Re: cath can
Post by: 1KWIKSIX on April 26 2013, 05:48:18 AM
Hey Brad, how bout posting some pictures of your set up. I'd also like to see how you've got your RJC (PCV Valve) plumbed in. 
Title: Re: cath can
Post by: Steve Wood on April 26 2013, 10:22:08 AM
I think obsessing over blm's is highly overrated in many cases.  Here is something I wrote the other day for a guy with a TT chip who keeps worrying about blm's and always wants to change the fuel pressure to "make them right".




BLM's- blm's work at idle and part throttle.  Depending upon the maf reading and the rpm, there are 16 possible blm settings.  Most of these are in effect between idle and 1500 rpm.  The last cell is from 1500 rpm and up but it DOES NOT control wide open throttle.  This is controlled by a programmed fuel curve in the chip.

BLM's that are programmed into the ecm can be adjusted thru a learning mode if the blm's are not consistently 128 and are being changed based upon input from the O2 sensor.  The ecm can adjust fueling if the  blm's are in a range from 105 to 150.  Therefore there is no great concern if, at any given time, the blm's are not 128.  Typically we say that 128 +/- 10 is a good range.  If the blm at a given cell based upon maf flow and rpm is always 120 and you take out enuf fuel pressure to make the blm read 128, then you are simply doing what the ecm is doing internally but you cannot see it do it...in theory, the car should run exactly the same whether you adjusted the pressure or not.  The problem is that you affected the entire fuel curve and not just the blm block that you were looking at when you decided your blm's were bad.  The ecm is a lot smarter than you are.

Look at this link-it spells it out in better detail and notice the rpm bands where the blm's are controlling the fueling.

 http://www.gnttype.org/techarea/faq/BLMINT.html (http://www.gnttype.org/techarea/faq/BLMINT.html)

the point I am trying to make is that obsessing over blms is largely a futile exercise.  Now, if blms are grossly out of whack from what you would expect on a modern chip, then you can start looking for a vacuum leak, a header leak (which fools the O2 sensor so that it sends erroneous info to the ecm which makes it adjust the fueling when it should not), or a fueling problem that may exist.

Note that the last cell covers a much larger rpm band but again, not wide open throttle.  The ecm slips into wide open throttle mode largely based upon Load (LV8).  Contrary to folk lore, tps voltage does not have much to do with it.

Now, on your chip  (TT), you have four parameters that you can adjust.

Parameter 1 controls wide open fueling in all four gears.

Parameter 2 controls wide open fueling in FIRST gear and it is a trim factor based off Parameter 1.  In other words you first set Parameter 1, then you look at your low gear fueling.  If you want to lean it down some to improve turbo spool and get a quicker launch from a standing start, you can.  If you have too much wheel spin from too much turbo spool, you could make it richer and cool down the charge a bit to slow down the spool a bit.  It really depends on how good the traction is and how much boost you are trying to leave on.

Parameter 3 is the timing in first and second.  Normally you can run more timing in first and second at the strip if you can hook the tires because there is less load on the engine and combustion chamber temps are not as high.  This can be a bit more dangerous on the street when the engine is hot because excess timing might cause detonation in that case where it may not on the strip because the engine is cooler.

Parameter 4 is timing for 3rd gear and 4 gear.  Again on the strip you can usually get by with additional timing unless you are hot lapping the car and the engine is not cooled down between runs.

As a rule, I am much more conservative on the street because engine conditions are usually not optimum-particularly if you have been driving in traffic or pounding on the car at boost multiple times.


So what about fuel pressure.  When you adjust fuel pressure you adjust every facet of fueling from idle to wide open throttle.  A change in fuel pressure affects flow by taking the square root of the (new fuel pressure divided by the old fuel pressure).  Therefore a change in fuel pressure is a relative small change in the actual delivery but it is more obvious at idle and low rpm than it is at higher rpms because the percentage of change compared to the fueling is larger due to the small amount of fuel used at idle and low rpm.

This is what I do, I set the fueling to 43 and I drive the car until it is fully warmed up and I have done some stop and go driving, then I stop and look at the O2s in gear idling.  If they are 780-800, I call it good and forget it.  Note that the O2s will change when you stop and the O2 sensor starts cooling down so your 780 might increase to 810 in a short period of time.  Don't be confused because this is a function of the stock o2 sensor not a change in fueling.

If, when I first stop, the o2s read something like 820, then I reduce the fuel pressure 1-2 psi and try it again, until my first readings upon stopping are in that 780-800 range.  Remember that the TT chips are open loop at idle so that first blm cell is not adjusting the fueling like the factory chip.  It does have some learning capability, however, so that is what I like to drive the car for a bit before beginning to play with the adjustments.

If everything is right, the O2s should be pretty stable wherever you set them and they should not be jumping around at idle due to the open loop feature.  That is why the idle is normally smoother and better.

When you come off idle, then the chip goes to closed loop an the o2s will jump around a lot more (at part throttle) as the ecm takes charge.

In essence, you can use the fuel pressure to set up your idle and low speed blms but I only look at the idle O2s first when I stop and the sensor is good and hot.

Now, remember that the fuel pressure affects the entire fueling range so the wot fueling will be a little leaner than what Eric put into his default  if you reduced fuel pressure at idle with the HOSE OFF so you need to look at the wot fueling to see if it needs adjusting.  Normally, it will probably not be noticeable.   Be sure to put the hose back on the regulator before you drive the car."



Title: Re: cath can
Post by: Scoobum on April 26 2013, 04:26:49 PM
  Those are the new numbers im shooting at
what breathers do you run ,I have a new set of TA covers
And is the RJC valve a check valve inline with the PVC


I have a pair of billet breathers from Full Throttle. I run the RJC valve in place of the PCV valve in the intake. I read on the other board of several guys BLM's going through the roof...but didn't get the same result with my engine. I'd call Jason...and ask his recommendation to either run it inline...or replace it with his valve. A few were saying that the RJC valve will act like a giant vacuum leak. Maybe Steve could elaborate...it's way over my head.
Title: Re: cath can
Post by: Steve Wood on April 26 2013, 08:51:12 PM
I don't have any modern experience so I really cannot elaborate.  Long ago, I ran a check valve and could not tell any real benefit.  Sometimes it is hard to share experiences because I have been running either open loop, or closed loop with a wb rather than a conventional chip since the early 90's.

I will say that a good pcv probably does not benefit from a check valve.  People worry about the pcv pressurizing the crankcase.  If you think about it, even if a pcv leaks a little when you blow thru it, there is a very small volume of air going thru it and the more boost you put on the valve, the more it tries to seal.  The crank case has a lot of volume in comparison so it takes a really bad valve to leak enuf to blow oil out in a few seconds.

Be just as easy to put a brass cut off valve in the line and close it when racing, I think.

In the end, my best advice is to do whatever works for you. :)

Oh, yeah...the factory pcv was designed to work with a closed system.  The first thing we do is to put breathers on the valve covers so we immediately F up the function anyway. :d
Title: Re: cath can
Post by: Tim Hensley on April 27 2013, 12:03:34 AM
the closed system remark about the PVC is a  one other thought to go to catch can.
Vacuum in the crank case is good and just driving around sucking air through the breathers seems bad
Title: Re: cath can
Post by: Steve Wood on April 27 2013, 12:40:12 AM
the only reason I can see to use a catch can is to cover up blow by.  It takes a pretty good pump to create a vacuum in the crank case
Title: Re: cath can
Post by: Tim Hensley on April 27 2013, 12:45:33 AM
I wont have blow by
Do I run the billet breathers and let it ride
Title: Re: cath can
Post by: Steve Wood on April 27 2013, 09:17:02 AM
you lost me.   
Title: Re: cath can
Post by: motorhead on April 27 2013, 09:53:18 AM
the only reason I can see to use a catch can is to cover up blow by.  It takes a pretty good pump to create a vacuum in the crank case

Catch-can to the inlet side of the turbo w/ a check valve, pcv on another circuit to the same... that is how I've designed it in my MCSS.
Title: Re: cath can
Post by: Tim Hensley on April 27 2013, 12:42:03 PM
I see how I lost you
I just put the PCV in  stock location
Put two billet breathers on the valve cover
Never mind the vacuum leak at cruse  not that bad.
MY BLMs have be +-10 with that set up in the past
Moterhead that is the way I thought I would do it
Thanks for the in put

Title: Re: cath can
Post by: Tim Hensley on May 12 2013, 01:08:51 PM
I have a 86 Vette 100% stock ,low miles took it for  Saturday cruse.It was idling about 1100 and hunting,and a noticeable knock@ WFO.
Pulled in and raised the hood found the grommet on the valve cover to the throttle plate  cracked ,
I had a new one put it on and Walla back to normal
? is my Buick has vented valve covers with a vacuum leak all the time and its just fine,dose the TT chip adjust for the leak?
SimplePortal 2.3.7 © 2008-2025, SimplePortal