Pontiac 400 valve covers with nice breather setup

[yellow1098Greg]

I'm looking for a nice set of valve covers for my built pontiac 400. It's having alittle crankcase pressure issue and needs to breath better. A double setup would be better I think but I'm sure u guys know more than me. Just looking for a nice looking set that will help the motor breath. Who makes em? And where can I get em? Thanks guys

Oh it's a 400 with forged crank rods and pistons with aluminum eheads and about a 9:1 compression ration

[72blackbird]

IMO you don't need dual breathers- run one on the passenger cover, and run the stock PCV line from the carb to the hole in the valley pan with a PCV valve. If you don't want to do this, you can get a few different styles of valve covers from Pacific Performance Racing.

http://www.pacificperformanceracing.com/index.html

Geno

[yellow1098Greg]

Right now on the passenger side there is the pipe from the valve cover to the air cleaner under the shaker. Would you replace that with a breather?? Thankyou for the link...

[72blackbird]

Right now on the passenger side there is the pipe from the valve cover to the air cleaner under the shaker. Would you replace that with a breather?? Thankyou for the link...
You shouldn't have to replace the OEM shaker breather setup if your PCV valve is working properly- what kind of issues are you having?

Geno

[Indymanjoe]

are you using an aftermarket valley pan?

[yellow1098Greg]

Just using the regular one from butler you can see it slightly in a pic here, along with the PCV


https://static1.pt-content.com/images/pt/2011/09/photopvc-1.jpg


I was having some crankcase pressure I think and was getting smoke on the highway, the pressure built up I assume and it happend at about 3500 rpm at 70ish mph for a sustained amount of time. That's the only time I was getting the smoke and alittle oil spread around underneath. At first I thought it was the rear main but that was replaced with the neoprene 40$ one from butler at least 3 times and it was sealed good.

Yesterday though I did replace the breather oil cap on the other side because the gasket was hard as a rock and drove the car at the rpm and mph range that it did for a short time (but not that long) and it was fine, tho it was still alittle wet underneath. Here's what it looked like, look at that pepperoni hard gasket......the replacement was identical but of course with a new fresh gasket ......


https://static1.pt-content.com/images/pt/2011/09/photobreathercap-1.jpg

But I was thinking and wondering if a bigger better breather setup might help it breath that much more...what do ya think?

[72blackbird]

Blow-by out of the breather is symptomatic of worn or improperly broken-in rings, or excessive ring-end gap- how many miles are on the engine?

Geno

[yellow1098Greg]

Hmmm well the motor was just freshly rebuilt about 600 miles ago

[72blackbird]

Hmmm well the motor was just freshly rebuilt about 600 miles ago

Hi Yellow,
Have you done compression and leakdown tests? Those would tell alot about the quality of the build.

Geno

[yellow1098Greg]

I haven't had chance to yet. But I plan on doing that ASAP.....any advice as to what numbers I should be looking for, for each test? Thanks

[72blackbird]

I haven't had chance to yet. But I plan on doing that ASAP.....any advice as to what numbers I should be looking for, for each test? Thanks

It all depends which size e-heads you're running- if you got 72cc heads you're at around 10-10.2:1 SCR. Your compression should be in the 195-210 psi range (also depends on cam size too). Leakdown with a fresh rebuild should be in the 2-5 percent range. Here's a thread over at Performance Years about leakdown testers.

http://forums.performanceyears.com/forums/showthread.php?t=708787&highlight=leakdown

Geno

[yellow1098Greg]

I'm actually running the 87cc heads, I bought them with the car. I assume the owner wanted to keep the compression down. They'll be good in that I eventually want a stroker.....I will get the cam specs tomorrow.... Thanks you for the link ill check it out

[72blackbird]

I'm actually running the 87cc heads, I bought them with the car. I assume the owner wanted to keep the compression down. They'll be good in that I eventually want a stroker.....I will get the cam specs tomorrow.... Thanks you for the link ill check it out

87cc e-heads are intended for a 455 or 461 stroker- on a .030 over 400 they yield a 8.8-9:1 SCR- about a point too low for maximum power output on a 400. But the bright side is you can make 425-450 hp on 87 octane with your current configuration.

Geno

[yellow1098Greg]

I think my compression numbers are on the lower side of that.....I have a edlebrock performer rpm cam, kind of mild. I'll get the numbers ASAP. But the pistons are also not the best for compression and performance i was told.

https://static1.pt-content.com/images/pt/2012/10/DSCN0122-1.jpg

https://static1.pt-content.com/images/pt/2012/10/DSCN0119-1.jpg

I didn't know much about getting a performance motor built 2 years ago and it was a budget build definitely....I have spent the last 2 years educating myself a lot and am enjoying driving the car until I get the money to build my stroker and the heads will work great with that. But in the mean time just trying to figure out how to not smoke down the highway.... So your advice about the leakdown and compression test will be my next step to figuring it out for sure.

[72blackbird]

Yellow,
Those two pics tell me alot about your build. If the builder chose those pistons for your 400, he most likely took other shortcuts and didn't use forged rods. The 8-brow reliefs are Sterling/Badger cast aluminum pistons, the cheapest piston most production engine-building companies use to remanufacture an engine. The chamfer around the edge plus the six extra valve reliefs lower your compression even further (8.3-8.5:1- like running 7:1 cast iron heads)- that combined with 87cc e-eheads tell me the builder knew very little about building a Pontiac V-8. I'd bet your ring end gaps are off as well, leading to excessive blow-by and oil getting into the breathers.

Even with e-heads I doubt you're currently making 400 hp, given the poor parts choices I see now. Hopefully your block isn't rebuilt more than once so you can do it right the next time around.

Geno

[yellow1098Greg]

I fully agree with you, guess it's called learning the hard way. All Iv learned about cars and this hobby of ours Iv read, never had anyone show me anything or had any classes. Pretty impressed with myself about how far Iv come in the last 2 years. Thanks for all your info and help geno

[72blackbird]

Yellow,
Glad I could shed some light on your blow-by issues- we all learned this information through experience or networking with other Pontiac V-8 owners, so it's always a learning process.

E-heads should have pretty good PC seals on the valve guides- I would pop your valve covers and see what condition those are in. I run them on both the intake and exhaust sides to keep excess oil out of the combustion chambers, but if your rings aren't set correctly they won't be enough to control the blow-by.

Geno

[yellow1098Greg]

Geno what exactly are the PC seals on the valve guides? .....the learning process continues....I'd like to take every step I can. Thanks again

[72blackbird]

Yellow,
PC seals are located on top of the valve guides- their job is to prevent excess oil from getting sucked into the combustion chambers. PC seals also fit snugly over the valve guide- the top of the guide is usually machined to allow the seal to fit tightly on the guide. OEM equivalents are umbrella-type seals that are located in the same position, but don't fit securely over the valve guide like PC-type seals do. These can be made of a cheaper grade rubber, and often harden and deteriorate over time.

Geno

[yellow1098Greg]

I haven't gotten around to checking out those PC seals yet....I need to read more about exactly what they are....I have a general idea by your description but not completely sure. Once I take off the valve covers and the gaskets where are they from there?

But regarding the situation...I replaced the entire breather that's in the pick a couple posts ago. New gasket and new breather itself. Maybe the other one clocked or something. But the gasket on the old one was definitely bad. I put the new one on and bam no more smoke....you think that could have actually been the fix?

[72blackbird]

I haven't gotten around to checking out those PC seals yet....I need to read more about exactly what they are....I have a general idea by your description but not completely sure. Once I take off the valve covers and the gaskets where are they from there?

But regarding the situation...I replaced the entire breather that's in the pick a couple posts ago. New gasket and new breather itself. Maybe the other one clocked or something. But the gasket on the old one was definitely bad. I put the new one on and bam no more smoke....you think that could have actually been the fix?

I would say yes- let us know if the smoking condition returns however.

[Grim]

Just using the regular one from butler you can see it slightly in a pic here, along with the PCV


https://static1.pt-content.com/images/pt/2011/09/photopvc-1.jpg


I was having some crankcase pressure I think and was getting smoke on the highway, the pressure built up I assume and it happend at about 3500 rpm at 70ish mph for a sustained amount of time. That's the only time I was getting the smoke and alittle oil spread around underneath. At first I thought it was the rear main but that was replaced with the neoprene 40$ one from butler at least 3 times and it was sealed good.

Yesterday though I did replace the breather oil cap on the other side because the gasket was hard as a rock and drove the car at the rpm and mph range that it did for a short time (but not that long) and it was fine, tho it was still alittle wet underneath. Here's what it looked like, look at that pepperoni hard gasket......the replacement was identical but of course with a new fresh gasket ......


https://static1.pt-content.com/images/pt/2011/09/photobreathercap-1.jpg

But I was thinking and wondering if a bigger better breather setup might help it breath that much more...what do ya think?


it happend at about 3500 rpm at 70ish mph for a sustained amount of time.

Thats part of the problem. 3.73 gears?


If your compression checks out then I think that may be most of your problem.

Big motors dont like that sort of RPM for extended runs Probably cooking the oil and being aerated by the crank. Windage tray would help some.

The sweet spot for cruise on most V8's is 2200ish. 3200 is where 4cyl motors like to run but they have half the rotating mass. With the 3.42s in mine I try to stay under 2800 rpm (65mph). HUGE drop in fuel consumption staying under 3k. Yeah I look like a old man in the slow lane but till I get some overdrive in mine thats where I am.

Another issue is you may be sucking oil up the PCV that slinging off the cam and lifters. Make sure your PCV grommet has the narrow slot.

Note the partly blocked area in the following link. Thats to try to keep oil out https://www.yearone.com/Product/1964-72-gto/mrg5425 The other Grommet (what I run in my aftermarket valley pan) has a slot. https://www.yearone.com/Product/1964-72-gto/al59

As for the breathers. I'm running Eddlebrock Elite valve covers and running a filtered breather in both covers since I run a Valley pan PCV. I fill through the PCV hole with a transmission funnel so I can push past the baffle at the bottom of the grommet all though I could pop a breather out but there is a baffle under it to keep oil being slung off the rockers in check..
https://www.pro-touring.com/attachment.php?attachmentid=66520&d=1350858354

[Skip Fix]

Is that the aluminum Butler valley pan or the steel reproduction? A lot of the aluminum valley pans just do not have enough baffling for the PCV valve and will suck oil in high vacuum situations even using the baffled grommet,longer tubes, inline filters-BTDT. In fact the 73-74 SD motors used the valve cover for the PCV not the valley cover.

[Grim]

Skip:
Me or the OP?
Mines the Year one version and I'm not real impressed with it. Little thin. I drive close to Year one a couple times a month so stopped by and picked it up when I found a rust hole in my factory unit. Wish I had ordered the one from Ames.

[Skip Fix]

The OP's pan. Can't see it under the intake.