Pcv?

[Dukes2fast]

On a 68 440 with 906 heads. I have a push in breather on the passenger side and a stock oil filler breather like this one (the one on the right) http://www.texasacres.com/parts/6/breather2.jpg
on the drivers side.
The stock vavle covers have baffles. I noticed oil getting a little messy on the covers from the drivers side breather. I hooked a hose hose up and routed it down to the frame. The question is how necessary is a PCV system? and is the oil by-passing the baffles and the breather any concern?
This is a fresh rebuild. KB hyper pistons with that big top ring gap...028

[dwc43]

First off that hose goes on the bottom of your air cleaner not hanging down by the frame. IT will provide filtered air to the engine as the PCV system works.

Check the PCV valve and the hose and the passage into the carb and intake to make sure it's open. If it's blocked it can build pressure and force oil out of just about anywhere including the breather cap.

That's too much ring gap even on the KB's. We use .018 as a max on the top rings even in our race engines that run them. THat's more than enough as long as the rest of your engine is properly tuned.

And yes, the PCV system is needed. Helps keep moisture from forming in the engine along with building prssures from blow by. On our race cars we delete the system and use two shielded breathers on the valve covers to vent the block. Not a good idea on street car though.

[Dukes2fast]

I am not running any PCV valve.

I spent hours on the phone with KB and they insisted on that gap.

[BigBlockDude]

Then install one and try it out.

[dwc43]

Originally Posted by Dukes2fast

I am not running any PCV valve.

I spent hours on the phone with KB and they insisted on that gap.

That's why you have the issue you have. Without the PCV valve and the breather hooked to the air cleaner your pressurizing the block and blowing oil out and that big gap aint helping.

Like I said, we run .018 on both top rings in our race engines with those pistons, but, those engines are in better tune than any street engine. The larger the gap, more blowby and that causes the block to build up with pressure.

This built up pressure can also blow out the weakest of gaskets as well as leak from the valve cover breather.

[Dukes2fast]

Not listening. The breather is not hooked to the air cleaner, it,s just a push in breather.

[ehostler]

I believe that '69 was the first year that the breather was connected to the air filter. Prior to that, it was a self contained design.

[John Kunkel]

Originally Posted by dwc43

That's too much ring gap even on the KB's.

KB states that their pistons need the extra top ring gap due to top land location, an absolute minimum of .0065" per inch of bore. With a .030" over 440 that computes to .028", just like the OP was advised.

We use .018 as a max on the top rings even in our race engines that run them. THat's more than enough as long as the rest of your engine is properly tuned.

You always seem to get away with doing things wrong. Luck?

[dgc333]

Once up to temperature a KB piston has no more end gap than any other piston when the gap is set to their recomendations. Because of the placement of the top ring you need to have more gap when the engine is cold to allow for the expansion do to the higher temps the ring sees.

Considering how adamant KB is about their end gap requirements anyone not following their recomendations is foolhardy and is asking for trouble.

I would eliminate one of the breathers and install a PCV valve, it will eliminate the oil getting all over the valve covers.

[dwc43]

Originally Posted by John Kunkel

KB states that their pistons need the extra top ring gap due to top land location, an absolute minimum of .0065" per inch of bore. With a .030" over 440 that computes to .028", just like the OP was advised.You always seem to get away with doing things wrong. Luck?

Luck has nothing to do with it. IT's just too much ring gap especialy if it's a race engine. I'd go tighter if I thought it would last.

[pishta]

Originally Posted by ehostler

I believe that '69 was the first year that the breather was connected to the air filter. Prior to that, it was a self contained design.

My CA spec '65 Barracuda S had a factory C.A.P. (clean air package) that included a different 273/4bbl AVS carb number and a PCV hooked to the carb and a push on breather/oil filler in the middle of the crinkle valve covers. It wasnt connected to the air cleaner either if that is what your "self contained" design was refering to. PCV prevents moisture build up from condensation by venting the water vapor and vents blow by. Prior to this design, they (FORD) used to hang a vent pipe cut at a 45 angle down by the lower frame rail. The air passing across it when driving sucked the same stuff out, did nothing at stop/idle though.

[Dukes2fast]

Thanks for the responses.
Doesn't the PCV send a certain amount of "dirty" air to the intake?

[DanL]

Depends on how you define "dirty" air.

Air entering the crankcase is filtered at the air cleaner (small separate filter or in the clean side of the main filter). It's drawn through the crankcase by manifold vacuum. So, it'll have vapors in it, but shouldn't be "dirty".

If it's a street engine, you'd do well to hook the PCV system up; it'll keep your oil in much better shape because it'll constantly be ventilated to keep the acidic vapors out of the crankcase, help reduce sludge, and it'll help keep the air around your car a little cleaner. A simple breather (sounds like how you have it set up now) doesn't guarantee much airflow through the crankcase, since it's only motivated by cylinder blow-by.

So, one valve cover vent to manifold vacuum (via the PCV valve), the other valve cover vent to the air cleaner.

You'll likely have to re-tune your idle settings.

[wilks3]

Yes, the PCV system lets some bypass and oil vapor in the engine. With rebuilt engine, blowby shouldn't be a problem. Are you using a high volume oil pump with stock main and rod clearance? If yes, think of the extra oil vapor in the valve covers. Thats where your oil mess is coming from. Just change your oil more often if not using the PCV system to keep the crude from forming in the engine. BTW my .060 over 440 with KB 184 hypers is .0284 top and .016 second as per KB, with no noticable blowby.

[pishta]

Originally Posted by Dukes2fast

Thanks for the responses.
Doesn't the PCV send a certain amount of "dirty" air to the intake?

I always called them a "controlled vacuum leak". The port I liked to hook them up to was the big nipple that was over the butterfly, only operational at throttle (vent fitting?) and I gutted the valve of its spring and check valve.

[ehostler]

There was one guy here (I'm forget who, so I'm not sure if he is still around) that developed a canister for the PCV system. It was inline with the PCV and allowed oil and anything else to collect in it, prior to entering the intake/carb.

[wilks3]

You use a in-line air-compressor water seperator for that. Sears or NAPA has them. Hook up between PCV and port vacuum. Some have the bottom drain, some you have to take the bowl off to clean.

[John Kunkel]

Originally Posted by dwc43

Luck has nothing to do with it. IT's just too much ring gap especialy if it's a race engine. I'd go tighter if I thought it would last.

Obviously you know more than the people who make the product. NOT!!!

Read dgc333's post, the running end gap is totally different than the static gap. KB has published pics of what happens when tight end gaps are used with their pistons.

[dwc43]

Originally Posted by John Kunkel

Obviously you know more than the people who make the product.

Read dgc333's post, the running end gap is totally different than the static gap. KB has published pics of what happens when tight end gaps are used with their pistons.

I must. And yes, I know what happens when the gap is too tight as well as what happens when it's too loose as well. Next test I want to do with them is some gapless rings and see if I can get rid of even more blowby. The .018 gap helps, but with a gapless ring it could be fine tuned a little better.

[dgc333]

But, following KB's recomendation for the first ring is not to loose but 0.018" IS to tight.

You still need to follow KB's end gap recomendations with gapless rings or you risk breaking them or the piston.

[Dick]

Originally Posted by John Kunkel

Obviously you know more than the people who make the product. NOT!!!

Read dgc333's post, the running end gap is totally different than the static gap. KB has published pics of what happens when tight end gaps are used with their pistons.

John, you just don't understand. The ring gap that KB insists on allows for heat on the top land. If your engine never runs, it isn't an issue, so dw can get by with minimal gap because his pistons never get hot.

[dwc43]

Originally Posted by Dick

John, you just don't understand. The ring gap that KB insists on allows for heat on the top land. If your engine never runs, it isn't an issue, so dw can get by with minimal gap because his pistons never get hot.

They run just fine and all the time. Just bring your money and a trailer so I can load you back up for the trip home.

[John Kunkel]

Originally Posted by dwc43

They run just fine and all the time.

Tell us about some of your recent victories; car number, track location, date, etc. Verifiable link.

[turbododge]

Like Dick and John said, too tight a top ring is only a problem if actually have an engine/car and run it. I don't see any Collins running in any class at Music City, so we just have to assume that the "living the dream" Sportsman ride is still just a dream in DW's head.

[dwc43]

I don't run under my name, but you already know that. Has to do with a legal issue that my lawyers pointed out some time ago. I metnioned it on here one time too. You need to read those release sheets they make you sign when you enter a tracks pit area. After that, you wont sign in under your name either, if your smart.

[dwc43]

Oh by the way, the last set of KB's we bought are 107's at .030 over. Just incase you are wondering what we are using. Still got the box if you want a pic of that ... lol!!!

[turbododge]

Yep, DW won't run under his own name for legal reasons, but "everyone" there knows him. Some legal protection that is. He also runs a car so secret that he can't take a picture of it, but "everyone" sees him race it every week, and win. Wow!, I guess I just don't know anything about the secret world of Tennessee racers. You can run an invisible car, under an assumed name, and be a hero.

By the way DW, whose name is your Nascar license in? If it isn't your name, that is fraud (it is at the track too) and a good, god-fearing, employed in " a type of law enforcement", upstanding citizen like yourself would never commit fraud, or would you?

By the way, let us know when the tooth fairy drops by to see you, we will all believe that too.

[dwc43]

Originally Posted by turbododge

Yep, DW won't run under his own name for legal reasons, but "everyone" there knows him.

Everyone does not know me, especially you.

Some legal protection that is. He also runs a car so secret that he can't take a picture of it, but "everyone" sees him race it every week, and win.

That's not exactly correct. The cars not secret at all, but some of hte stuff we do to it is. That's how you stay competitive. And I never said I win every week. As for psoting pics, I saw someone ( I want mention there screen name) but the car has too much negative RF camber that can be easily seen from the pic. First thing it tells me is that his set up is way off. Too soft a T bar or sway bar allowing too much travel or the upper A arm is too long. I got that from a pic, and it was the first thing I spotted on that car. That's why I don't post pics of current cars. Now I have posted pics of my old cars though. And at years in if one of mine ends up being obsolete due to some new rules that came out this year, you'll get to see some pics of it. But not until.

Wow!, I guess I just don't know anything

You got part of it right anyways.

By the way DW, whose name is your Nascar license in? If it isn't your name, that is fraud (it is at the track too) and a good, god-fearing, employed in " a type of law enforcement", upstanding citizen like yourself would never commit fraud, or would you.

First off, that's none of your business. And it's not fraud at that track. One reason I have a lawyer and a damned good one at that. And no, I would not knowingly commit fraud.

[John Kunkel]

Originally Posted by dwc43

I don't run under my name, but you already know that. Has to do with a legal issue that my lawyers pointed out some time ago. I metnioned it on here one time too. You need to read those release sheets they make you sign when you enter a tracks pit area. After that, you wont sign in under your name either, if your smart.

Pretty much the B.S. answer I expected, kinda like your "secret proof" regarding synthetic oils.

You have never in the history of this or any other forum offered any proof to substantiate your claims.

[dwc43]

Originally Posted by John Kunkel

Pretty much the B.S. answer I expected, kinda like your "secret proof" regarding synthetic oils.

You have never in the history of this or any other forum offered any proof to substantiate your claims.

Well, it's not B.S that's just your uninformed opinion. And I don't have to offer you any proof, it's my business how we set up our racing team, not anyone elses. I have to protect my interest, not make everyone else happy.