hey guys, dinking around in the shop this weekend and came up with this gem of an idea. we didnt want to cut a hole in the old corvette valve covers but needed a pvc valve set up. the car/motor in question is running an electric pump so this is what we came up with ~some pix to follow more or less we took the mech fuel pump block off plate and added some thickness, taped it and threaded in a fitting ~it was also baffled by the way - then for the trail runs we hooked up a length of red fuel line to the correct spot on the carb. this way we could run it and spot if anything was coming threw the line and ect. seems to have worked preety nice! it will end up hardlined and no one will ever notice it, and you wont have to drill holes and come up with something thats at best a half ass fix. ill post pix in a sec. oh, and although it seems like a great way to go if you see any giant flaw that im not thinking up please speak up.
What intake are you running. You have to have an intake for the system to breath thru. I like the idea.
His intake would be the oil fill tube as long as it has a breather and not a sealed cap. Looks like it should work fine.
i saw that the older V8 chevys before the pcv in the valve cover had a breather that bolted under the intake manifold just to the left side of the distributer shaft (if looking at the front of the motor) i wonder if they made the blocks after that without that hole? or if its still molded into it.
tim I tried this too.. however I noticed erratic "smoke" out the pipe.. which indicated to me that my baffle wasn't sufficient.. you may have better luck.. rather than fight the power.. I just went with a breather. as my valve covers arent that special..
Minor point, but PCV works best to suck out water and other vapors from the entire crankcase, if valve and fresh air intake are on opposite sides and/or ends of the crankcase (front and rear of the intake manifold, opposite rocker covers), too.
I just picked up an oil fill pcv setup for mine and was just going to block off one side of the valve cover breathers. The right side seems to let out more vapors than the left so I figure that'll be the side I'll leave open.The smaller breathers are allready blocked off. Does anyone see a problem with that ?
Just an FYI - GM also made an oil filler tube with a pcv valve threaded into the backside of the tube. It's another option, like say for a guy that's running a mechanical pump but doesn't want to cut holes in his valve covers and wants to run a PCV system. Scroll down about 1/3 page and look at the motor pic... http://www.jalopyjournal.com/forum/showthread.php?t=256757&showall=1
a friend of mine drilled a hole in the back side of his intake manifold (Edelbrock Performer if i remember right) just behind the carb in a flat area. he installed the PCV in that. he also drilled and tapped the underside to hold a baffle in place (use Loc-Tite on the fasteners). he then just bent up some large brake line tubing to connect from the vacuum port on the carb to the PCV. VERY clean set up and it works like a champ.
good to see that you were looking at this Danimal..was going to send you this thread for Courts Truck.
or you could just drill a hole in the intake manifold bolts (second ones from the rear) braze a little tube in it and run some small rubber hose to a vacuum port on the carb it worked for me tk
sjould have a little more drive around time this weekend and we'll see if that baffles goign tow ork or not
so update from a couple thousand hard miles, that car gets beat on haha. and its working just perfect
Yup. Without that fresh air and cross flow pattern you'll want to change your oil more often to get the vapors and acid-forming potential out. Of course modern oils are much better than the old ones, so you can still probably get away with a "normal" change.
nice i like the idea. i dont want to cut my V/C. need to add breathers tho, and prolly a system like this, as mines blown out the front and rear intake seals, lol.
What will probably happen with the PCV valve so low is that it will suck up oil laden air and you'll have some smoking when driving on the highway. If you're spinning up some revs - like my 32 roadster, 80 mph = 3300 rpm - and you cruise for a few miles at 80, flooring the throttle will lay down a cloud of smoke that will put a cropduster to shame. I've done several things, but what will help is to get some good baffling under the PCV hose fitting where it picks up vapor laden air. Some late Buicks (455 etc.) have the PCV valve in the valley, through the intake manifold right behind the carb. Other late Buicks have the PCV valve in the rocker cover. Both locations need a good baffle. Especially the valley location. The valley is laden with oil contaminated air and it looks like your PCV will be in an even oil-richer area far as droplets of oil flying about goes. In my case, highway gears will help. (Going from 3.70 to 3.00). As will a better baffling setup. If you have a well-sealed engine, good rings, valves, compression etc. and you're using oil it's probably due to the PCV setup is carrying oil into the intake. A hundred miles will use 1-2 quarts of oil in highway running. Fwiw - here's a PCV diagram.
on a completely different note, i'm diggin the Charlies Speed & Machine decal on the coil.... they still around? I grew up in that area...my big block stuff, back in the day used to pay Rose's salary, i'd imagine
YearOne and Classic Industries sell that style of oil fill tube. It was also stock on my '62 283 for California emissions. Spend the extra couple bucks for the correct resto-spec twist-on oil fill cap, rather than the cheap Mr. Gasket generic one; I found the Mr. Gasket one didn't seal at all. It didn't even snug down tight. -Brad
Here's the shit ya' need and what Brad54 was talking about. Except, these are from my 30 year old stash of stuff in original GM boxes. Included is a pick of the tube in the back of the block for '67 and earlier. Sometimes GM put the PCV in this hose connection. I also have the part# for the painted filler tube with the threaded bung. There's another style filler tube that takes a really neat looking 4 tabed twist cap. I think Ecklers has all this shit.
Does anyone have any pics of what shape a good baffle would be or what it would look like for maximum effectiveness, say for a valley pan? Some shapes must be better than others, right?
Just in case somebody goes looking for it, the hole for that fitting in the back of the block is where the oil pressure sender is (at least on my '87 block) I left that sender where it was and will be using an aftermarket gauge sender in the threaded hole above the oil filter. If I go to hole-less covers, I will remove the old sender and do what Brad54 is doing.
I had some issues with the PCV valve placement itself. I drilled a port in the back of the intake manifold, built a baffle under it, put a nipple on it and ran the hose up to the air cleaner base, inboard of the air filter element. This is the "intake" portion of the system. I used the same PCV that Modified Driver shows...got it from the parts store. The diagram I saw in the YO Catalog showed it in the port on the fill tube, just like Modified has it. The other end goes to the port on the base of the carb. When I installed it like that, the flow on the PCV was backwards, and what ended up happening was my air cleaner base filled with oil--even though I have a very good baffle under the port. (It's a small 1/4-inch hole drilled in a piece of aluminum, welded to the bottom of the intake. Only way in, only way out.) I put a 45-degree brass fitting on the base of the carb (just like the one that was on the original 2bbl carb on the 283 that was in the truck), screwed the PCV to the carb that way, put a barbed nipple into the filler tube and ran the hose that way. No more problem. So the air enters the engine thru the air cleaner assembly, runs down to the lifter valley thru a port in the back of the intake, up thru the fill tube, thru a hose running the the PCV valve on the base of the carb, which is set up to run from the hose nipple to the threads. I don't know if the OE valve was originally oriented threads to nipple or not, but we cut one apart to make sure I had it installed correctly. Frank, how does your NOS one flow? C9: where did that diagram come from? I've looked for one like that for a long time--I'd like to weave it into a tech article. -Brad
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