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On our old engines, I don't see the point of an oil catch can. Why not just put an air filter on the end of the breather tube? Excess oil will eventually just run back into the area under the cam cover, which is fine, right?

Am I missing something?
 

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I think catch cans are a racing or track requirement if you have converted to open breathing.
Pete
 

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Depends on engine build and use. Below is a 1600 "street" engine, which is actually a pure race engine I drive on the street. It has both a front GTA breather and rear breather. Both are set up like road-draft tubes, just ending below the frame rails. Normally, nothing comes in or is blown out other than at high rpm, where a very fine oil mist blows out. Little condenses on the clear tubes, but what-ever does, drips out. This is a fairly fresh engine, and essentially no measurable oil is lost from the sump between oil changes. Track use with this same engine requires catch cans.
 

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Depends on motor and use.
My "other" car had a very tired motor. I ran the vent hose to a regular oil bottle. Not pretty, but kept the air filters alive.
My wife had a turbocharged mini. I installed a catch can and was amazed at how much oily condensation I would drain out every month or so. Prior to the catch can the misty oil helped contribute to a burned exhaust valve.
On my spider, I just have a 18" length of hose with the small filter on the end.
 

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While the subject is open (pardon my intrusion if i’m Hijacking your thread), can you guys tell me what the short tube bent downward coming out of the back of my block is? ‘67 1600 By the way. I would say draft tube but it’s not long enough to reach down into the airstream.

Thanks
Mark
 

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Crankcase blowby outlet/vent.

On my Sprint GT, I installed a hose and attached an oil can full of steel wool to catch the blowby oil. Fair amount, that. Later engines have an oil vapor collector installed as stock. They tend to be only a little efficient.

In the 164, you can get oil running into the rubber intake bellows, downstream from the AFM, from the OVC outlet pipe which is connected to the intake bellows, esp if the little drain/return tube at the bottom of the OVC is plugged with crud, a common occurrence.
 

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Hi Del,
Here's a "catch". Sometimes engines inhale through breathers and will suck stuff in. Fine steel wool dust is not too good. Ferrari, on the double breathers on the old V-12's, used copper wool, and we sometimes replace it today with either more copper wool (heavier than steel wool) or stainless steel pot scrubbers! The latter have big curlies of SS, quite heavy, wont corrode as copper wool does, and cannot be inhaled.
 

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I misspoke when I said steel wool, as what I had was bronze wool from another project.
My father used it when he rebuilt aircraft engines. I was just thinking generic when I wrote the above. You are correct otherwise. Merry Christmas.
 

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I'm open to air on my Spider.

On the S-4 Spider's there is a gasket where the breather hose attaches to the cam cover which has a small hole in it, way less then half the size as the CCV opening.

I replaced that gasket to utilize the full opening to reduce crank case pressure.

The catch can is on the driver's side of the engine bay. I backe dated the dip stick tube to one with a oil return nipple on it, so whatever goes to the catch can gets returned to the crank case.

There is an oil return nipple on the right side of the block that can be used too. That's the one the later Spiders used with the stock oil vapor separator.
 

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I think we should not do open hoses anymore. Chuck a catch can on and stop oil being leaked on our roads, causing motorcycle, etc. accidents!
Pete
 

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I'm open to air on my Spider.

On the S-4 Spider's there is a gasket where the breather hose attaches to the cam cover which has a small hole in it, way less then half the size as the CCV opening.

I replaced that gasket to utilize the full opening to reduce crank case pressure.

The catch can is on the driver's side of the engine bay. I backe dated the dip stick tube to one with a oil return nipple on it, so whatever goes to the catch can gets returned to the crank case.

There is an oil return nipple on the right side of the block that can be used too. That's the one the later Spiders used with the stock oil vapor separator.
I like the oil pressure gauge in the corner, I assume thats a mechanical one to check what the real pressure is? I'm planning on doing the same, but to run the gauge inside the car to keep an eye on it whilst on the road.
 

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I think we should not do open hoses anymore. Chuck a catch can on and stop oil being leaked on our roads, causing motorcycle, etc. accidents!
Pete
What about the other option of just having the breather hose point up rather than down and sticking a little air filter on the end of it?
Yep
Pete
 

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I like the oil pressure gauge in the corner, I assume thats a mechanical one to check what the real pressure is? I'm planning on doing the same, but to run the gauge inside the car to keep an eye on it whilst on the road.
Yes it's a mechanical oil pressure gauge.

I use to have it in the cab but took it out years ago, all the plumbing was there so I rehooked it up in the engine bay a couple of weeks ago.

After a while you stop looking at the gauges in a street car and with the stock low oil pressure warning light in front of you, it will tell you when to turn the engine off. The stock gauge while rather vague, back by a mechanical gauge in the engine bay to check, it works for me.

The mechanical oil gauge while not in the cabin will still let you know when you oil pressure is lower then normal at idle and with the throttle cable you can check the pressure at higher rpm's too.
 

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Yes it's a mechanical oil pressure gauge.

I use to have it in the cab but took it out years ago, all the plumbing was there so I rehooked it up in the engine bay a couple of weeks ago.

After a while you stop looking at the gauges in a street car and with the stock low oil pressure warning light in front of you, it will tell you when to turn the engine off. The stock gauge while rather vague, back by a mechanical gauge in the engine bay to check, it works for me.

The mechanical oil gauge while not in the cabin will still let you know when you oil pressure is lower then normal at idle and with the throttle cable you can check the pressure at higher rpm's too.
Where did you get the 'T' Piece from to split the senders?
 
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