pcv again.

[Ian Turgeon]

Im trying to think of a way to simplify life and keep oil out of the induction track, and off my valve covers.

to my understanding:

under vacuum:
drivers side is inlet, passanger side is exhaust.
vacuum from both exhaust branches of the tee on the passanger valve cover flow crankcase fumes into the intake.

under boost:
both valve covers become exhaust?? (or is this only true if we have failing rings)
the pcv valve connecting to the throttle body closes due to boost, but the other branch to the intake is open as vacuum is present in the intake tube.


So since there is always vacuum on the one branch of the passanger valve cover, why is there a branch for the throttle body section?

Assuming I could place a catch-can & oil/air-seperator on the passanger side, and eliminate the tb branch, would there be enough flow out of the crank case? How could I prevent oil leakage from the driver's side without using a seperate catch can.


Then theres air pumps, Id still need a catch can, but I wouldnt have to worry about vacuum. but theres extra hardware and amperage draw.


any clues out there?

 

[ParTyBoy]

Re: pcv again.

Im trying to think of a way to simplify life and keep oil out of the induction track, and off my valve covers.

to my understanding:

under vacuum:
drivers side is inlet, passanger side is exhaust.
vacuum from both exhaust branches of the tee on the passanger valve cover flow crankcase fumes into the intake.

under boost:
both valve covers become exhaust?? (or is this only true if we have failing rings)
the pcv valve connecting to the throttle body closes due to boost, but the other branch to the intake is open as vacuum is present in the intake tube.


So since there is always vacuum on the one branch of the passanger valve cover, why is there a branch for the throttle body section?

Assuming I could place a catch-can & oil/air-seperator on the passanger side, and eliminate the tb branch, would there be enough flow out of the crank case? How could I prevent oil leakage from the driver's side without using a seperate catch can.


Then theres air pumps, Id still need a catch can, but I wouldnt have to worry about vacuum. but theres extra hardware and amperage draw.


any clues out there?

Wish I had a scanner to scan the diagram from the Syclone supplement.. but here it goes... basically forced air travels into the airbox upon acceleration.. PCV hose connected to the bottom of the airbox forces air under velocity into the driver's side crankcase .. air runs through intake/exhaust cycle comes out the passenger's side T fitting to the 2 pcv valves.. reason for two valves??? Basically it's for emissions... rear pcv sucks vapors back into intake to become ignited/thoroughly burned again.. while front pcv shoots vapors back into intake tube... keep in mind air under velocity is being sucked into the turbo.. so vapors are pushed/sucked into turbo.. to be burned in the engine before exiting be back to the exhaust...

At least that's my understanding of the PCV system..

 

[Ian Turgeon]

looked at the supliment.

the drivers side is the frech air inlet. which in case of excessive blow by or extended high load conditions, will act as an exhaust into the air box.

the passanger side is as I described, but the manual explains:

"To maintain idle quality, the PCV valve directs flow
to the throttle body when intake manifold pressure is
low. At high manifold pressures, the system directs
flow to the air cleaner duct.
that system will function as intended."

meaning the valve on the tb branch closes under boost. I can only conclude that there is not enough vacuum in the intake tube before the turbo at idle to draw air out of the crank case? I know it will suffice in boost as thats how it works now. I guess the answer is to try something, and see how it effects idle, if at all

 

[canadian]

Find a Camaro or Vette smog pump on eBay and hook the inlet side to the passenger side PCV system, and you can use the outlet side of the pump to a catch can, or down under the truck.

Steve Gavic has done this on his Ty, I have a smog pump sitting in the garage right now, just need to figure out how to wire it up. Mabye someone can ask Steve to take pictures of his setup? Or anybody else done this?

-- Warren

 

[ParTyBoy]

looked at the supliment.

the drivers side is the frech air inlet. which in case of excessive blow by or extended high load conditions, will act as an exhaust into the air box.

the passanger side is as I described, but the manual explains:

"To maintain idle quality, the PCV valve directs flow
to the throttle body when intake manifold pressure is
low. At high manifold pressures, the system directs
flow to the air cleaner duct.
that system will function as intended."

meaning the valve on the tb branch closes under boost. I can only conclude that there is not enough vacuum in the intake tube before the turbo at idle to draw air out of the crank case? I know it will suffice in boost as thats how it works now. I guess the answer is to try something, and see how it effects idle, if at all

Took way more time looking at it than i did :lol: :lol: learn something new everyday... :lol:

 

[Ian Turgeon]

I'm leaning towards that as it would help get rid of some speculation. isnt to good for enviromentalists though.

 

[canadian]

I doubt you not having a "correct" PCV system is going to make much of a difference in the environment. At least nothing measurable except for your conscience (then again, you can't measure that either).

 

[Hu Ryde]

I got a smog pump out of a 99 ls1 firebird. It worked for a while until I went on a long highway drive. It was pulling air from the pass side valve cover. It would have worked alot better if I hooked it up to the driverside pushing air in the driverside valvecover. Eventually it burnt the pump motor out when it was used as a vac pump.

I plan on trying another pump when I get back from school using it to force air through the crankcase instead of sucking it out of the motor. HTH got the pump for $45 from a ls1 bb fourm member.

 

[Hu Ryde]

Sorry for the huge size.

 

[Ian Turgeon]

thanks for the pics.. so this is a pusher only? I would think the ideal thing would be to have a puller.

 

[Hu Ryde]

Yeah, it's a pusher only. Found that out after it melted down. Like I said I tried it as a puller on the pass side and it burnt up on a long hw drive. I plan on giving it another attempt as a pusher on the driver side after school.

 

[skata]

Yeah, it's a pusher only. Found that out after it melted down. Like I said I tried it as a puller on the pass side and it burnt up on a long hw drive. I plan on giving it another attempt as a pusher on the driver side after school.

i dont understand why you want to push air into the crankcase. so where does the crankcase gas exit? into pass pcv valve? where are the blow-by gasses goin to go? especially while boostin? you will be building pressure up against the pump and the pcv valves and oil and crankcase gasses will try to squeeze out wherever it can.

the whole purpose of the pcv system is to prevent the hydrocarbon emissions(blow-by) from goin into the atmoshpere. that is why they are routed into the intake to be burned by the engine combustion.
the crankcase does not need fresh air. the contaminants are collected in the oil, thats why it turns black and that is why oil is changed frequently.

if you have to be emissions compliant, the crankcase blow-by needs to be routed into the intake to be burnt into a cleaner gas. while the intake manifold is under moderate vacuum, the pcv valves suck the blow-by out of the engine's crankcase.
but when the manifold pressure increases and boost builds the pcv valves shut and the blow-by gets pushed out of the drivers side vent. if the pcv valves do not close when the blow-by increases the engine would perform poorly. if you have a aftermarket intake, you need to run the drivers side vent into the intake to be emissions compliant.

now if you dont want to be emissions approved ::baddevil:: , you can do away with the pcv system if you'd like and just vent the crankcase by running hoses from the top of the valve covers, to down under the truck where the crankcase gasses could just escape into the air and out the back of the truck. if you just put filters on the valve covers, you will get oil everywhere, and the crankcase gasses/smoke will get inside your truck easier.

now if you want a air pump setup, you need to put a filter/filters on one valve cover, and the other valve cover vent would run into the intake side of a air pump. i dont know what kind of pump you could use, especially one that can take heat, but a smog is designed to push only.

well thats my 2 cents worth, and sorry if i wrote too much, ::blahblah:: .

 

[syntax]

I agree, you dont want to force air into either valve cover under any circumstance, the only way air should enter the crankcase is per a compensation of pressure loss from the opposite valve cover sucking air out. If you use the pump and force air into the crankcase/valve cover it could be at a larger volume than the other side is sucking out per the pcv valves, and youll increase the chance of blow-by. the best setup would be a large volume vacuum pump on one valve cover and a breather on the other, this will cause a slight vacuum condition in the crankcase seal the rings properly and decrease the chance of blowby, the breather in-turn will only replace what the vacuum pump is pulling out, and you will have nill chance of a pressurized crankcase.

 

[Hu Ryde]

By forcing air in the driver side it is working the same as sucking air from the pass side. I plan on using no pcv valves and having a filter on the intake side of the pump so nothing get's in there and contaminates it. Oh btw I don't have to worry about emissions anyway, I have historical tags. This is the only logical way to have it work without burning the pump up again. Remember, the theory here is to remove the PC gasses. This is what the pump will do. It will blow all the gasses out into the atmosphere.

 

[jwaller]

sorry jesse it dont work like that...the point isnt to just blow the gasses out. your actually trying to creat a vacume in the crankcase. doing this makes the rings seat better leading to more hp.....do you see anybody blowing air into the crankcase in a dragcar? no all you see are vacume pumps. putting the crankcase under vacume makes more hp !

 

[canadian]

I just cross-referenced your pump with the one I have here and it looks a fair bit different. Check out the pics of mine below:

Looks like this one has an inlet and an outlet port on it. I plan on running a breather on the drivers side valve cover, and running the passenger side PCV lines to the "in" side of the pump, then running a hose to either a catch can or atmosphere on the "out" side of the pump.

 

[Ian Turgeon]

but when the manifold pressure increases and boost builds the pcv valves shut and the blow-by gets pushed out of the drivers side vent. if the pcv valves do not close when the blow-by increases the engine would perform poorly.

However our system does not entirely operate this way.

The passanger side has two valves, one before and one after the turbo. So only one sees boost, while the other recieves vacuum caused by turbo's pull. I dont know if at this point there is enough pressure in the crankcase (or vacuum at the air box) to push gasses out the drivers side.

I do agree we need to create vacuum in the crankcase. Although pushing air into the crank case, would push air out the opposite valvecover. This would only effectively increase pressure in the crankcase.

 

[Hu Ryde]

Good point waller, I guess I should re-evaluate the situation if I decide to do anything in that direction for a HP mod.

O'well everything thing with these trucks is trial and error, it's just that somepeople try and help others with new ideas and I was just giving my opinions on what worked and what didnt in my particular situation.

canadian,
I have seen that pump also on the V-6 and LT1 camaros at the local junkyards. Like I said mine was from a 99+ LS1 firebird. Not sure if yours will hold up any different than mine. My pump basically melted down, the brush/contact holder was held in place with a plastic retainer and it got so hot that it melted the holder and the brushes then moved out of contact and pushed through and basically self destructed because of heat. It's a very good idea but I don't think the pumps are designed to be used as a vaccume style, they are a source of + air. This is why I think mine melted down.

If you are trying to use this as anything like the moroso type pumps it will not work. I know this!

sorry jesse it dont work like that...the point isnt to just blow the gasses out. your actually trying to creat a vacume in the crankcase. doing this makes the rings seat better leading to more hp.....do you see anybody blowing air into the crankcase in a dragcar? no all you see are vacume pumps. putting the crankcase under vacume makes more hp !

Yes john I know that, that was not my intentions at all. I was not looking for more hp out of this mod, I am simply looking for a way to keep all the pc charge out of the motor completely. Thus blowing it out of the motor instead of sucking it out, do you forsee a problem with this?

Again I was not looking for a horsepower mod when this was done, just a way to remove the positive crank gasses out of the motor without having the motor injest it or remove it itself. Looking for a 3rd party system to removes these gasses.

No flame intended, just opinions here, I am always open to new ways to look at things.

If I'm ass backwards let me know.

 

[canadian]

i know steve gavic was using one on his truck. not sure if it's still on there or how long it will/has held up. do you think yours self destructed because of the constant running of it, or the heat of the crankcase fumes? i'm pretty sure these weren't designed to move a lot of hot air. i also noticed on mine there seems to be a little filter on the "in" barb. wondering if that will get cloged up with oil residue or not as well.

 

[Hu Ryde]

From what I heard from the guy that I bought mine off of it was ok to run it all the time, so I don't know on that part. I did completely disassemble mine and there wasnt much oil or anything in there. I had just rebuilt the top end of my motor and there is virtually no blow-by so the impellers were clean. I truthfully don't know why it overheated, other than the fact that I was using it to try and suck air and not to blow the air it like how it was designed for. So who knows, I am definately going to keep my eyes open for another pump because it worked great until it melted down.