• Just passing by? Feel free to reply to discussions, no account needed.
    Or, quickly register using Facebook or create an account the old fashioned way.

BUILD LAME Turbo V6 Camaro

v6buicks

TCG Elite Member
TCG Blue
Oct 22, 2018
5,223
12,538
Franklin, IN

Mr_Roboto

Doing the jobs nobody wants to
TCG Blue
Feb 4, 2012
22,873
24,529
Nashotah, Wisconsin (AKA not Illinois)
  • Wow
Reactions: v6buicks

v6buicks

TCG Elite Member
TCG Blue
Oct 22, 2018
5,223
12,538
Franklin, IN
I'm seeing now that they're doing this in conjunction with the PCV valve. I was kind of guessing this was an old school thing made before "HD" PCVs were available, but it actually makes more sense to me this way. PCV works at idle/cruise. Evac pump works under boost and if your engine is healthy you shouldn't have an oiled intake.

I might try buying an NOS PCV. I saw one on ebay the other day. The originals are good because they have an oring that will actually seal boost. Nobody that I know of makes them like that for 3800s anymore. :(
 

Mr_Roboto

Doing the jobs nobody wants to
TCG Blue
Feb 4, 2012
22,873
24,529
Nashotah, Wisconsin (AKA not Illinois)
I'm seeing now that they're doing this in conjunction with the PCV valve. I was kind of guessing this was an old school thing made before "HD" PCVs were available, but it actually makes more sense to me this way. PCV works at idle/cruise. Evac pump works under boost and if your engine is healthy you shouldn't have an oiled intake.

I might try buying an NOS PCV. I saw one on ebay the other day. The originals are good because they have an oring that will actually seal boost. Nobody that I know of makes them like that for 3800s anymore. :(

Why not an external check valve?
 

v6buicks

TCG Elite Member
TCG Blue
Oct 22, 2018
5,223
12,538
Franklin, IN
Why not an external check valve?
Isn't the amount of air/oil vapor to the intake was supposed to be metered? I thought the valve was supposed to do that. I mostly just like that adding an NOS valve back in the intake because it would be completely unseen and already in a pretty ideal spot over the valley. If this NOS valve does not seal like its supposed to (I went ahead and bought it) I might be interested in the external check valve idea. Are you saying just to plumb it from valve cover to intake?

This crankcase evacuation stuff gets complicated. Both sides of turbobuick.com have good arguments for and against the vacuum pump. For now, I lean towards it. A lot of the issues I have could still be inside the engine. For instance this engine has a high mile bottom end with at least one worn out cylinder head. I probably have decent blow by along with worn guides just huffing into the crankcase like crazy which not only crates the crankcase tornadoes™ Turbocharged400sbc Turbocharged400sbc which slows the crank down, but also cause some pressure build up that is not fully escaping via catch can. I know it's not happening now because there's only ever fuel and water in it. However, I have few intentions of actually fixing those engine problems. :LOL: I will continue running shitty SBEs, so blow-by is just the nature of my game. I may need a little extra help in the ring sealing department especially when I'm running a stick shift and do a fair amount of engine braking.

What confuses me a bit here is the actual steps and order of operations. This Pablo guy is about as clear as his pictures, but one guy specifically says he has a similar system with stock PCV valve and intake hose. Then he added a valve cover vent -> vacuum pump -> to vented catch can. Seems like a solid system. I'm not sure if the water separator between the valve cover and pump is necessary but the amount of water I get running E85 has me thinking it would be smart. Does anyone think this order could be switched up? Maybe valve cover -> sealed catch can -> pump -> atmosphere? I'm sure the pump would appreciate that.
 

sktchy3.8

it'll work til it doesnt
TCG Blue
Jul 27, 2021
3,908
6,611
Talk Talking To Myself GIF by Facepunch Studios
 

sktchy3.8

it'll work til it doesnt
TCG Blue
Jul 27, 2021
3,908
6,611
I'm not worried about the idle airflow thing so much as what the oil vapor does to the octane of your fuel and what happens when you start sucking it back into the intake. Like, I've tried this, it really didn't end well, and I hope you have better results if you continue to pursue it.
 

v6buicks

TCG Elite Member
TCG Blue
Oct 22, 2018
5,223
12,538
Franklin, IN
I mean throw a check valve in series with a PCV. yeah you'll fuck your idle up if you don't have air leaking in a controlled way from somewhere quite plausibly.
Ohhh In series. I would have to snap a picture to illustrate this better, but that may be a tough order to serve. The PCV is internal to the intake. Here's a poor diagram.
1681845477704.png

The valve (bottom) sits in a bore in the upper intake plenum with a passage going directly down to the valley. The valve is held down with a spring (middle) between the valve and the cover plate (top) bolted to the outside of the intake. I cannot remember how far this spring is compressed. To ensure that the valve was actually being a valve, I think I could drill a hole in the cover plate, install a bulkhead fitting with a barb on the inside and replace the spring with a hose. Then the check valve could be in series on the outside of the intake. The locating pin for the spring on the valve also doubles as a hose barb for other GM applications like the GN. If there's enough room even for both fittings, the hose would have to be slightly too long just to ensure that the OD of the valve is sealing on it's oring when the cover plate is bolted down. This could would be a pretty tough and critical measurement becaue hoses aren't springs. lol

OOO 💡

What if my PCV plug isn't plugging at all? Could the extreme vacuum from my intake while engine braking and crank case tornadoes underneath be overcoming that spring pressure? If I recall correctly it's a pretty tough spring, but this too is worth looking at.

I'm not worried about the idle airflow thing so much as what the oil vapor does to the octane of your fuel and what happens when you start sucking it back into the intake. Like, I've tried this, it really didn't end well, and I hope you have better results if you continue to pursue it.
Even the wildest of racecars have PCV systems that use intake vacuum for certain functions. It's just a matter of getting the right check valves and amount of volume caught in baffles so you don't suck up anything but air. Some of those racecars have catch cans for catch cans and hold multiple gallons so that there's 0 chance of engine damage. I'm not going that far, but I should be able to make something work safely.
 
  • Like
Reactions: sktchy3.8

sktchy3.8

it'll work til it doesnt
TCG Blue
Jul 27, 2021
3,908
6,611
I guess if your gonna keep after at least make sure it's pulling from behind the maf, I feel like the vapors hitting it contributed to what happened with mine but that engine did fine up until I tried to run the can back in pre turbo and as soon as I did that car has been parked out back getting parts stolen off of it ever since lol
 

Turbocharged400sbc

3800 > ALL
TCG Blue
Jun 16, 2007
31,143
12,564
hangover park IL
Yes to run an external coalescing filter/oil separator on panda's GTP i ended up drilling and tapping the top of the PCV cover for a right angle nipple that let me shove a hose over the PCV and over the inside of the 90゚ nipple in place of the spring.

I also Drilled and tapped a port on the side of the PCV tower for the return to the air inlet from the oil separator. ....
 

Turbocharged400sbc

3800 > ALL
TCG Blue
Jun 16, 2007
31,143
12,564
hangover park IL
I deep threaded the cover I made it so that the elbow screwed almost all the way down to where you could barely put a hose on the nipple on the outside......

Then before final install I ground away the threads on the end that stick through into a small short nipple for the hose to slide over/center on.

If I recall I cut the hose so that it stuck up a little over an 8th of an inch before bolting down.

Hd trans cooler hose leftovers.

No cheap shit fer the inner "spring" hose
 

v6buicks

TCG Elite Member
TCG Blue
Oct 22, 2018
5,223
12,538
Franklin, IN
I deep threaded the cover I made it so that the elbow screwed almost all the way down to where you could barely put a hose on the nipple on the outside......

Then before final install I ground away the threads on the end that stick through into a small short nipple for the hose to slide over/center on.

If I recall I cut the hose so that it stuck up a little over an 8th of an inch before bolting down.

Hd trans cooler hose leftovers.

No cheap shit fer the inner "spring" hose
Old School Yes GIF
 

v6buicks

TCG Elite Member
TCG Blue
Oct 22, 2018
5,223
12,538
Franklin, IN
Machining stuff is where I start to get a little iffy. It sounds like that's the best way to get a short nipple close to the cover though. There is not a ton of room in there.

Let's say I have the stock PCV ran externally. Now what? My guess is water separator -> catch can -> check valve -> back to intake. Then the valve cover set-up ends up being a totally separate system with the vacuum pump. It's just too bad that the I wouldn't be pulling from all three spots at the same time.
 

Turbocharged400sbc

3800 > ALL
TCG Blue
Jun 16, 2007
31,143
12,564
hangover park IL
The right angle nipple coming out the top that is connected to the nipple on the piece of evolve goes to your catch can/centrifugal oil separater.... It leaves there devoid of as much oil as your extractor can do and enters into the intake of the engine behind the throttle.

On the M90PCV tower I do this by tapping the side of the tower and putting a port there so that the gas flows around the outside of the rubber Spring nose And goes through the factory pcv hole before the rotors.

You are basically splicing into the factory PCV gas path
 
  • Like
Reactions: v6buicks