CrispyRX7

iTrader: (139)

Tyson,
I'd like to agree but I'm still leary. It would be awesome if that simple tap worked wouldn't it?
I actually was going to go out to my "private" skidpad with the stickies on and run in the clockwise direction with the catch can drain hose simply plumbed to the top of the dipstick tube (with no check valve) and see what happened. Only problem is can I drag the brakes sufficiently to get the car into a boosted condition and generate some cranckase "pressure" to sumulate real track conditions without looping the car ever few feet?
Maybe this weekend.
Crispy

TYSON

It's easy enough to add one later.

CrispyRX7

iTrader: (139)

With or without the engine in the car?
Crispy

TYSON

The checkvalve should not require engine removal, I hope!

OC94Rx7

Go for it Crispy
By the time I recieve my catch tank and get the baster from my sister in California...my car will be down for the winter so, I really hope it works!

CrispyRX7

iTrader: (139)

Tyson,
LOL
I thought you were referring to tapping a fitting into the side of the center housing at the base of the filler neck.
Crispy

TYSON

What, you don't want to do this when the engine is running?

Kaotic Dan

This may be a stupid thought, but what about capping the nipples on the side of the oil filler tube, and tapping a new line coming out of the top of the oil cap. You can do this with any cheap metal oil cap.

DamonB

That's essentially how the catch can is plumbed now. The cars pull enough g's under cornering to slosh it all the way up to the cap.

SleepR1

No, it's a smart idea. We're just trying to figure out how to make this idea better

CrispyRX7

iTrader: (139)

So I've been trying to hunt down a suitable check valve...just in case one is needed. Lots of net surfing and I returned to old reliable McMaster-Carr. Anyone have any thoughts on the acceptability of the "Brass Spring-Loaded Poppet Check Valves-Low-Cracking PSI"
listed on page 368? male-male 1/8" with a Viton seat.
http://www.mcmaster.com/
The thought was with a pipe fitting on one end this valve would be much easier to tap a hole and screw it in rather than having to fab a fitting and then having an in-line check valve. Kinda kills two birds with one stone.
Thoughts?
Crispy

80-CU.IN.T

That is what I did. #10 Earls 90 degree fitting running into a 1 Quart aluminum can with a K&N filter on top. It has a drain #6 Earls which will be plumbed to the front turbo drain back hole. I haven't plumbed it yet but soon. A check valve is a very good idea but I don't think it will be nessessary with my setup. RX6 single

TYSON

Crispy, with a 6" deep bottle of oil you would only get about .2 psi of pressure at the bottom. Looks like you would need the plastic ones there for them to open when the bottle is full.

The ones you mention are the closest metal ones though. If you can mount it low enough below your bottle they might work. Gotta watch out for the pressure loss in the tubing you would use.

SleepR1

Tyson, I LOVE your avatar quote. It's right up there with my new Speed Sauce Racing motto, "It's always sumpthin"...

CrispyRX7

iTrader: (139)

Tyson,
This is kinda what I figured to. There simply isn't enough head to drive the oil. Course that could work in our favor which may argue why a check valve is even needed if the oil pan never sees more than .5 psi of pressure either with a vented to atm. catch can.
I wanted a metal valve simply for longevity but like you saw I could find none with the specs needed for this appl.
Crispy

DamonB

What you need isn't so much a "valve" but a trap door similar to the hinged baffles in an oil pan. Ideally mounted right to the bottom of the catch can. Even so, I would try this without any sort of check valve first. No sense to add the complexity if it's not needed and it can easily be added later if testing shows it is needed.

CrispyRX7

iTrader: (139)

Damon,
This is essentially just how a check valve works
Imagine a toilet flapper valve housed inside a small plastic housing. It's the same thing FWIW.
But I hear ya...gonna try my skidpad tests this weekend hopefully if the weather holds out. Temps have dropped like a rock the past few days! Hopefully I can get the tires to stick enough
Crispy

DamonB

I thought what you were describing a valve that still had a spring? The "trap door" will open with practically no pressure needed.

TYSON

Trap door ones are difficult to mount vertically, which would be easiest for this application.

TYSON

Pretty much describes my whole summer this year....

CrispyRX7

iTrader: (139)

So the weather was nice a sunny this weekend and and temps were as good as they were going to get so I called my friend and we headed off to my "skidpad" with a G-tech for some loops. The ultimate goal of the testing was to see if the catch can will drain to the dipstick tube and into the pan.

TEST 1) Lets see if I can get some oil up into the catch can just doing loops. Run the oil half way down the dipstick..as I do on the track anyways. At the limit of adhesion on my **2 YEAR OLD** WAY heat cycled A032R's not a drop in the catch can. Test sustained lateral G's at a pretty crappy 0.94. Yeah the tires are toast.

TEST2) Maybe I need some crankcase pressure to "push" some oil into the catch can. Same scenario except with parking brake well and truly engaged. With boost hovering at around 10psi at the same limits of adhesion lapping the pad yielded not a drop in the catch can. So for all of you guys using street tires or heat cycled R-compound tires you should have no worries. There simply isn't enough grip to get oil thrown up into the catch can..or at leats that's my belief.

TEST3) Now to hook up the catch can to dipstick tube drain line. Because no oil would come up into the catch can "naturally" I 3/4 filled the catch can with fresh oil.
With me in the car ready to go my friend quickly opeing the drain valve and closed the hood and off I went dragging the parking brake to keep the car in boost.
About 10 laps later I pull in and pop the hood. The result? Oil everywhere. From appearences most on the ground under the car. The question is was it oil spilling out from the lateral G's or from crankcase pressure pushing *up* through the drain line. Given the narrow neck of the catch can I'd have to say crankcase pressure bubbling up through the oil in the can combined with the lateral G's. The catch can was about a 1/4 full.

TEST4) Well crap....is the can draining at all? With the car idling I refill the can with oil to see if it will drain. Sure enough down it goes..although VERY slowly.

So the can will drain into the dipstick tube under unboosted conditions but is it fast enough to handle what is pushed up during cornering and will it drain when in boost in a straight line? The only real test IMO at this point is to try it at the track. So who's gonna be first?

Crispy

ptrhahn

iTrader: (9)

Hey chris,
I was able to generate enough grip w/ your worn A032s to puke a ton of oil out the top of the catch can and all over my hood at VIR.

'course i still run the hose to the can off the regular filler neck nipple. I had to run it about 2/3 the way down, and even then it filled the can.

CrispyRX7

iTrader: (139)

Pete,
Thanks for the datapoint. I guess I was looking at the whole package as I too was able to pump oil into the catch can with the yoks also under the same conditions a year or so ago. But now consider the catch can hose tap location, ie. cap vs filler neck nipple. Still good info though.
Crispy

gfelber

Hmm...

I use the same catch can without a plumbed drain and run on three tracks out here (Seattle area), all counterclockwise. On two of the tracks there are only a couple of moderate-G right handers. I get very little oil in the catch can. On the other track, however, there are a few high-G right handers which fill up the catch tank very quickly (in about 15 minutes with 1/2 dipstick).

I don't think it's boost that's filling them as I would expect to see that on the other two tracks (and these are sustained high boost tracks) as well as autocrosses (I get very little or nothing in the can autocrossing with Hoosiers).

However, it may be possible that a pressurized crankcase (if that's the case) and a plumbed catch can full of oil might overflow in the engine bay.

On the other hand, if the crankcase is pressured to a fair degree under boost I would think that most of us would be getting oil everywhere in the engine bay from the dipstick tube/dipstick junction since the dipstick merely rests in the tube (i.e., it doesn't provide a very tight seal)...doesn't seem to be the case with me pre-catch can. Anyone else?

Regards,

Gene

CrispyRX7

iTrader: (139)

Gene,
Exactly my experience.

Agree. Quite possibly the reason I saw not a drop
in the can running *in boost* at maximum grip in
a right hand circle for 30 seconds or more continuously.

Bingo. So how to drain the catch can so it's never full and therefore this condition no longer is a problem?

With the vented to atmosphere catch can the crankcase is never "pressurized" per sae. But the tube from the filler neck to the catch can is seeing a fair bit of flow in the form of blowby. Get oil anywhere near that filler neck pickup point and it is going to get pushed out into the catch can by the blowby when under boost.

Without oil near the pickup point even when under boost the blowby into the catch can is going to be nothing more than gas.

And just note even in the OE conditionthe crankcase sees no pressure as the PCV lines take car of that. So yes the dipstick will/should just sit there. FWIW I had a friend (arcwelder) with a stuck PCV valve and he was constantly blowing the dispstick out.

Crispy
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