Was exchanged over PM or were you being sarcastic? I'd like to see it drawn out too if that's available.
Rookie2
PCV 101 for Forced Induction 80's (1 Viewer)
- Thread starter SUMOTOY
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Was exchanged over PM or were you being sarcastic? I'd like to see it drawn out too if that's available.
Rookie2
Was exchanged over PM or were you being sarcastic? I'd like to see it drawn out too if that's available.
Rookie2
he mentioned here that he would draw it out but in a PM he reconsidered. When I get home this weekend I'll pull some info off of TIS and start a new thread.
We've pretty much got all we are going to get here and if it takes pictures then we're on our own. The major stumbling block for me is that after looking at the Supra setup I don't see anything significantly different than a stock cruiser that has had a SC put on it. Yet he says that his changes basically recreate the Supra setup.
And when I try to apply what is written here it doesn't make sense.
- Thread starter
- #43
Rick
You can keep the thread on PCV here if you want, I'd love to see what you explained here in post 29 on the supra turbo PCV:
I read that interpretation to mean that there is a PCV line to the inlet side of the turbocharger, which most turbo PCV systems have. This means that vacuum is present in the crankcase under boost.
When I rerouted to the brake booster tap in the SC prechamber, when the SC is under boost, the PCV is now "vented to a spot pre-compressor"
The definition of "a spot Pre-compressor" just means before the turbo inlet on a turbocharged application, and before the compressor blades of the Supercharger on the SC app.
PCV under boost in both the supra turbo, and the SC.
Scott Justusson
on my 96 the brake booster comes off of the intake pleneum so I know I"m not sure where you are tapping into it on your truck.
On the PCV line that goes to the PS of the valve cover where does that end up on your truck?
On mine it goes to the throttle body which when moved to the front of the SC is pre-compressor.
On the PCV line that goes to the PS of the valve cover where does that end up on your truck?
On mine it goes to the throttle body which when moved to the front of the SC is pre-compressor.
- Thread starter
- #45
The TRD supercharger has you reroute the brake booster to a vacuum source precompressor as shown in the pic. You can see the fitting in the pic
To an idle port on the throttle body. That one is unchanged from stock.
It's not a continuous vacuum source under boost or in a non boosted truck actually. The reason for two PCV sources. The one that goes to the throttle body is considered an idle only PCV circuit. Think of it this way Rick, if you put the brake booster feed on that throttle port, you would have no power assist on the brakes other than at idle.
The SC prechamber becomes the 'plenum' on the SC application. Exactly why the brake booster feed was move there too. If you move the brake booster to a better vacuum source than the 'plenum', then it follows that plenum PCV should be moved to the same vacuum source.
Yer scarin me man!
Scott J
one of the problems for me is that since I don't know what I'm looking at in your picture I don't no what I'm seeing.
For me to understand things I need to visualize them in my head. Until that happens I basically don't get it. It's just how I'm wired, can't help it. That's why a drawing is so helpful for me in my understanding anything.
Here you basically posted a written solution with a picture that I don't know what I'm looking at.
Had you taken several pictures at better angles showing the original routing and explained how that wasn't working. And then followed it up with similar pictures and it's explanation I wouldn't have a problem.
Since I'm probably going to install a turbo I'd like to understand this type of stuff ahead of time.
For me to understand things I need to visualize them in my head. Until that happens I basically don't get it. It's just how I'm wired, can't help it. That's why a drawing is so helpful for me in my understanding anything.
Here you basically posted a written solution with a picture that I don't know what I'm looking at.
Had you taken several pictures at better angles showing the original routing and explained how that wasn't working. And then followed it up with similar pictures and it's explanation I wouldn't have a problem.
Since I'm probably going to install a turbo I'd like to understand this type of stuff ahead of time.
- Thread starter
- #47
Rick:
I can answer specific questions, and can address misconceptions. I'm not used to putting up pics, but did so here.
I really think this is simple. With the original vacuum feed, when you have boost in the manifold, you have no pcv during boost, it closes the PCV valve, turbo or supercharger it doesn't matter.
In either a turbo or a supercharger system, to get pcv under boost, you relocate the PCV feed from the intake manifold to a vacuum port pre compressor, turbo or supercharger it doesn't matter.
The only routing I changed was capping the intake runner port, and moving it pre compressor. The IPCV is hooked up to the same place on the Tbody as it was in the stock truck. The only difference is that the SC changes the location of the Tbody in the engine bay.
Again, if you have any specific questions, PM would be more effective. This is a lot of back and forth over a very simple procedure and concept.
SJ
Reroute the PCV valve feed
I can answer specific questions, and can address misconceptions. I'm not used to putting up pics, but did so here.
I really think this is simple. With the original vacuum feed, when you have boost in the manifold, you have no pcv during boost, it closes the PCV valve, turbo or supercharger it doesn't matter.
In either a turbo or a supercharger system, to get pcv under boost, you relocate the PCV feed from the intake manifold to a vacuum port pre compressor, turbo or supercharger it doesn't matter.
The only routing I changed was capping the intake runner port, and moving it pre compressor. The IPCV is hooked up to the same place on the Tbody as it was in the stock truck. The only difference is that the SC changes the location of the Tbody in the engine bay.
Again, if you have any specific questions, PM would be more effective. This is a lot of back and forth over a very simple procedure and concept.
SJ
Reroute the PCV valve feed
Scott, if Rick isn't there yet, than a lot of other meb4ers aren't either. Solving technical details via PM is not the correct approach here.
Make a drawing upload it and talk about it. Seems like a reasonable request to me.
Make a drawing upload it and talk about it. Seems like a reasonable request to me.
- Thread starter
- #49
Hmm, a very basic concept... Here's my suggestion, someone take a pic of a stock truck PCV, since I no longer have a stock truck. That said, the only change I made is identified clearly in the pics I did take.
Moving PCV to a vacuum source under boost isn't difficult. Possibly conceptualizing how an 80 makes boost is? Or possibly what PCV does?
This is the first forum I've been on where uploading pics is part of the posting game. A lot of technical information is exchanged without this luxury on many other boards.
Or, someone else can give it a try, this is less than a 1
concept and execution. SJ
SUMOTOY
Nice write up.. but I wish you would have done it before I spent many long hours running all my hoses/lines under the Intercooler.
I guess I can't win them all.... and now I have a new project when the yard is finished..
later
Bret
Nice write up.. but I wish you would have done it before I spent many long hours running all my hoses/lines under the Intercooler.
I guess I can't win them all.... and now I have a new project when the yard is finished..
later
Bret
When I get home I'll draw up something in cad. It won't be pretty but it will allow you to more easily get through to me
Scott I understand the theory of how a PCV system works, it's the hardware side of what you did that has me confused.
on my stock truck
the hose on the DS of the valve cover w/PCV valve goes to the plenum behind the throttle plate. This is the one you capped off.
the hose on the PS of the valve cover goes to the throttle body in front of the throttle plate.
When moving the throttle body over to be in front of the compressor it puts that hose from the PS of the valve cover in front of the throttle plate and the compressor.
When I looked at the Supra diagram this is how it is setup with the exception that the compressor and throttle plate is reversed.
Is the 93-94s setup differently stock from the 95+ trucks?
on my stock truck
the hose on the DS of the valve cover w/PCV valve goes to the plenum behind the throttle plate. This is the one you capped off.
the hose on the PS of the valve cover goes to the throttle body in front of the throttle plate.
When moving the throttle body over to be in front of the compressor it puts that hose from the PS of the valve cover in front of the throttle plate and the compressor.
When I looked at the Supra diagram this is how it is setup with the exception that the compressor and throttle plate is reversed.
Is the 93-94s setup differently stock from the 95+ trucks?
Maybe these 3 pictures will help the conversation
Here is a stock set-up ( Overlook Nakmans cooker)
Here is a super charged setup (mine)
Here is Scotts modification
Missing a good angle for the new feed port. The pic makes it look like it is going where the left hose went
Here is a stock set-up ( Overlook Nakmans cooker)
Here is a super charged setup (mine)
Here is Scotts modification
Missing a good angle for the new feed port. The pic makes it look like it is going where the left hose went
Ken, your picture of how your hoses are is exactly as I described and is how the Supra is setup.
Sumotoy, explain to me why the stock pvc on the intake manifold not throttlebody that is closed during low vacuum/high throttle is not closed when under pressure.
The TRD unit looks fine as designed if the parts are in working condition.
Worse case as I see it, the intake manifold pcv valve leaks some due to age/gunk buildup. But the throttlebody pcv tube has a venturi effect/pressure drop from high airflow and scavanges any excess pressue buildup in the crankcase. Are you suggesting that the pressure leak from the intake manifold pcv is higher than the vent tubes capacity?
Easy solution to me is use a turbo speced/sprung pcv.
I reread your post 1 again. As I understand you are suggesting that there is no venturi effect or pressure drop at the throttlebody pcv tube?
The TRD unit looks fine as designed if the parts are in working condition.
Worse case as I see it, the intake manifold pcv valve leaks some due to age/gunk buildup. But the throttlebody pcv tube has a venturi effect/pressure drop from high airflow and scavanges any excess pressue buildup in the crankcase. Are you suggesting that the pressure leak from the intake manifold pcv is higher than the vent tubes capacity?
Easy solution to me is use a turbo speced/sprung pcv.
I reread your post 1 again. As I understand you are suggesting that there is no venturi effect or pressure drop at the throttlebody pcv tube?
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It was in the back of my mind that maybe the Supra had a different PCV valve but I wanted to understand were the issue was better.
As I already mentioned I believe the main benefit is not having to worry about weather or not the PCV valve is closing off completely when under boost. I am not particularly concerned about pressurizing the crank case but I sure don't want any boost to bleed off.
- Thread starter
- #58
No it's not Rick. Here is the supra setup, notice the hose going to the intake after the MAF pre turbo compressor inlet. That is the stock "on boost" pcv routing found in most turbo applications including the supra turbo as you described it. It's also exactly the same stock PCV routing and location found on my ex 22RTE 4 runner turbo. Vacuum PCV under boost, always.
SJ
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so is that the line with the valve or the open one?
So I think I figured out what you did.
A normal SC truck has:
1 line that goes from the PS valve cover over to the throttle body pre throttle plate and compressor.
1 line on the DS has the PCV valve and is attached to the intake plenum post throttle plate and compressor.
Now there is a nipple located on the SC that is post throttle plate but pre compressor for supplying vacuum to the brake booster.
What you did was to take the line from the intake plenum and "T" it into that booster line so it is now post throttle plate but pre compressor.
is this right?
A normal SC truck has:
1 line that goes from the PS valve cover over to the throttle body pre throttle plate and compressor.
1 line on the DS has the PCV valve and is attached to the intake plenum post throttle plate and compressor.
Now there is a nipple located on the SC that is post throttle plate but pre compressor for supplying vacuum to the brake booster.
What you did was to take the line from the intake plenum and "T" it into that booster line so it is now post throttle plate but pre compressor.
is this right?
