[Build Thread] -- Journey to 700+ WHP [Supercharger]

[cupcakez]

Originally Posted by Optimiser

This is a previous post I made regarding my experience with this issue:

During my first session at a recent track day I was getting oil leaking out of the breather valve on my Vortech supercharger. I'm thinking it's because I'm over spinning with pulley upgrades as it didn't leak at a previous track day when the pulleys were stock. It doesn't leak at all driving on the road. It's just leaks at constant high RPM.
Is there any fix for this other than "downgrading" the pulleys which I don't want to do. Would getting a "Trim" upgrade with the high speed bearings and impeller fix this?
Has anyone else experienced this at the track with an "over spinning" Rotrex supercharger?
The only possible solution I could find on the net was to reduce the oil level in the supercharger by 1/4 to 1/2 oz out of it's normal 4 oz max fill, but I've not tried that yet.

What some of the mustang guys with SCs do is replace the vented plug with the shipping plug for the SC that way there is no way for oil to escape.
Downside is you risk too much pressure buildup and nay or may not break your current seals.

I would only use that solution as a last resort.

If your blower is stock internals and still requires 4oz of oil, I would stay with the 4 oz.
But if its still leaking, I would try a tiny less and see how that works.

I only confidently put less oil because the impeller volume size is a bit bigger than stock v3 sci impeller.

Now what I will say is I have only revved it to maybe 4 or 5rpms at max I think 6rpm by accident in low gears.

From that I still have yet to see any oil leaks but I hope I dont see any oil leaks in the high RPM range!!!

[Optimiser]

Originally Posted by cupcakez

What some of the mustang guys with SCs do is replace the vented plug with the shipping plug for the SC that way there is no way for oil to escape.
Downside is you risk too much pressure buildup and nay or may not break your current seals.

I would only use that solution as a last resort.

If your blower is stock internals and still requires 4oz of oil, I would stay with the 4 oz.
But if its still leaking, I would try a tiny less and see how that works.

I only confidently put less oil because the impeller volume size is a bit bigger than stock v3 sci impeller.

Now what I will say is I have only revved it to maybe 4 or 5rpms at max I think 6rpm by accident in low gears.

From that I still have yet to see any oil leaks but I hope I dont see any oil leaks in the high RPM range!!!

I am just now getting the 928 Motorsports impeller and bearings/seal upgrade/replacement and I'm not clear on how that changes the volume of oil required in the supercharger as you mention.

[cupcakez]

Originally Posted by Optimiser

I am just now getting the 928 Motorsports impeller and bearings/seal upgrade/replacement and I'm not clear on how that changes the volume of oil required in the supercharger as you mention.

Look closely at the impellers.
One has more vanes than the other = More volume of space used up in the blower.

Unless I'm mistaken and that they are still taking up the exact amount of space just one has smaller but more multiple vanes than the other one which has less vanes but bigger?

Not sure. lol.
I'm still in the testing phase too :P

[Chuck33079]

Originally Posted by cupcakez

Look closely at the impellers.
One has more vanes than the other = More volume of space used up in the blower.

Unless I'm mistaken and that they are still taking up the exact amount of space just one has smaller but more multiple vanes than the other one which has less vanes but bigger?

Not sure. lol.
I'm still in the testing phase too :P

Correct me if I'm wrong, but the vanes are in the air stream, and have no bearing on anything relating to oil volume?

[cupcakez]

Originally Posted by Chuck33079

Correct me if I'm wrong, but the vanes are in the air stream, and have no bearing on anything relating to oil volume?

Oh right lol I think thats correct. I had a feeling I was wrong somewhere but couldnt quite put my finger on it.
I guess I may have the same issue then, at higher rpms for possibly even long periods of time, oil may shoot out haha.

Makes sense though cause otherwise oil would shoot out everywhere lmao

Edit:
I take that back.

I am looking closer at it now.
The vanes that are part of the airflow sure dont touch oil but I would assume maybe the extra metal leading UP to that vane (if that makes any sense) = tiny bit more space used up?

I mean they both have 16 lines or whatever you want to call it. But both do not have 16 vanes sticking out for air.

I dont even know if that entire blades side touches oil or not. I would now assume it doesnt otherwise it would spill from the front into the filter right?

Kay Im out of ideas. lol

[Rusty]

Originally Posted by cupcakez

Oh right lol I think thats correct. I had a feeling I was wrong somewhere but couldnt quite put my finger on it.
I guess I may have the same issue then, at higher rpms for possibly even long periods of time, oil may shoot out haha.

Makes sense though cause otherwise oil would shoot out everywhere lmao

Edit:
I take that back.

I am looking closer at it now.
The vanes that are part of the airflow sure dont touch oil but I would assume maybe the extra metal leading UP to that vane (if that makes any sense) = tiny bit more space used up?

I mean they both have 16 lines or whatever you want to call it. But both do not have 16 vanes sticking out for air.

I dont even know if that entire blades side touches oil or not. I would now assume it doesnt otherwise it would spill from the front into the filter right?

Kay Im out of ideas. lol

All the vanes on the impeller are in the air flow. No part of the impeller touches oil. The oil is in the middle housing. Think what is happening is a combination of things. Oil level, high rpm, fluid expansion, poor venting. The oil capacity of the housing isn't that much. With high rpms, the oil gets splashed around a lot. Also with the high rpms, you heat which makes the oil expanses. And then you have a pipe plug with a simple hole drilled into it. One thing to do. You need to do is make a shield on the bottom of the vent plug to keep oil away from it. And put some type of breather on top of it. Also what you could do. Put a hose fitting where the vent plug goes. A length of hose. Then you need an orifice of some type in the hose. Then put the end of the hose into a catch can.

When I worked for ElliottTurboMachinery. I built and repair stuff like this.

[redondoaveb]

Here's an article from SOHO Motorsports blog where they mention over spinning the supercharger and oil coming out of the breather at high rpm/boost. Of course I think Ben's car was seeing about 18psi.
https://sohomotorsports.com/700-rwhp...d-nissan-370z/

[Optimiser]

Originally Posted by Rusty

All the vanes on the impeller are in the air flow. No part of the impeller touches oil. The oil is in the middle housing. Think what is happening is a combination of things. Oil level, high rpm, fluid expansion, poor venting. The oil capacity of the housing isn't that much. With high rpms, the oil gets splashed around a lot. Also with the high rpms, you heat which makes the oil expanses. And then you have a pipe plug with a simple hole drilled into it. One thing to do. You need to do is make a shield on the bottom of the vent plug to keep oil away from it. And put some type of breather on top of it. Also what you could do. Put a hose fitting where the vent plug goes. A length of hose. Then you need an orifice of some type in the hose. Then put the end of the hose into a catch can.

When I worked for ElliottTurboMachinery. I built and repair stuff like this.

"Also what you could do. Put a hose fitting where the vent plug goes. A length of hose. Then you need an orifice of some type in the hose. Then put the end of the hose into a catch can."

This is exactly what I've been thinking and have purchased a few cheap bits and pieces to make something like this up.

[Optimiser]

Originally Posted by Chuck33079

Correct me if I'm wrong, but the vanes are in the air stream, and have no bearing on anything relating to oil volume?

That was exactly my point.