Changing newer motor to vent like 67 f/finned vette covers

[grancuda]

I am considering drilling out the boss on my Edelbrock performer rpm intake and putting in a '67 & down vent tube so I can run vette style finned covers. I really like the look of the older vette covers. I drive my truck 75mi round trip daily and the breather looses too much oil beause of chrome valve covers. Will this system be a cleaner set-up? The motor is a tight 30k mile crate motor.

Anyone have pics of this setup on thiers?

[BAGNDRAGIT]

so your looking to go with the road draft tube setup kinda thing??

[hayhauler71]

Do your chrome valve covers have baffles in them ? Lot of the cheep valve covers don't and will dump oil out your breather. Also make sure your pcv valve is working. I myself recommend using a pcv valve on a daily driver with baffles in both valve covers.

[Livrat]

The only problem with putting in the front intake fill tube and using the early Vette valve covers with no breather holes is that your engine will not breath properly..
The 68 and earlier engines also had a hole in the back of the block with a baffle under the intake manifold then either used a "road draft" tube or a adapter to run a hose to a vacumn source with a PCV valve.. if you add just the tube into your intake your engine will still build up crankcase pressure and spew oil out.

Your chrome valve covers more than likely do not had a baffle under the breather holes in to keep oil from splashing up into your breather caps.. or you do not have a PVC system connected..

[grancuda]

I do have the baffles but they are the cheap $20 chrome with a slight bit of slack in the gromets.

[hayhauler71]

Does your engine possibly have excessive blow bye

[grancuda]

No, I run 4:10 gears and run 65-70 to work so the rpms are up there

[powell72]

I have an old Offy intake with the fill tube on it and finned no hole valve covers with a later (no road draft tube) block. I drilled and tapped the back of my intake and have a fitting screwed in it with a hose connected to it running to a screw in PCV valve from a '67 Chevelle with a 283 in the carb. This is the correct style that pulls instead of pushes unlike the similar looking Corvette ones.
An engine breathes the best with either a PCV in one cover and a breather in the other, side to side; or front to back, with the breather on the fill tube and a PCV or road draft in the rear.
The only problem with this setup is even with a baffle on the underside of the intake you might still pull oil up into your intake because of how heavily oil contaminated the crackcase air is in the lifter valley. This is a common problem with having a PCV in the intake. I am still trying to work the bugs out of my setup. I went on a road trip that was 300 miles and used 2 quarts of oil. My truck used no oil before I did this mod. I see a few guys on The H.A.M.B. with the same problem, and they have yet to find a solution also.

Here's my setup-

[mclairmo]

I have a pcv valve in the driver side valve cover hooked up to the base of my Holley 3310 carb and an elbow in the Passenger side valve cover with a large hose going into the bottom of my factory GM open element air cleaner and no problems with that at all. Have new grommets that are tight and all new hoses. No oil anywhere ever. I suggest you buy new grommets and get rid of the breathers.

[cdowns]

mr gasket makes a gromet with built in baffels to go into cheapo no baffle valve covers its better than being open but still worse than quality baffeled valve covers

[texnician01]

I am using a newer block without the road draft tube and an older intake with the oil filler, I have chevrolet script valve covers so i do not want to poke holes in them for a PCV. I drilled and tapped an area in the back of the intake manifold to put in a thread in PCV valve similar to what Chryslers use. I soon found that I was consuming my oil in a hurry. I built a baffle and mounted it on the bottom side of my intake similar to what the old road draft tubes had. Since then it has done very well with oil. I still have enough pressure to vent out of the oil fill once in a while and leave a nice oil film, I just keep it clean and it is fine. I think oil film is impossible to get rid of when you have a vented system like the road draft and oil filler vent. My engine should not have excessive blow by either it is only a few years old on a once in a while use basis.

[mr48chev]

Originally Posted by hayhauler71

Does your engine possibly have excessive blow bye

+1 if it is blowing oil out the breathers there is too much pressure in the crankcase due to either excessive blow by or the pcv valve not working correctly. The crankcase ventilation system works by air being drawn in the breather, through the engine and out the pcv or road draft tube and it won't vent properly if you don't have one or the other hooked up. Two breathers will just allow the fumes to blow out the breathers. Ok on a drag car that only goes a quarter mile at a time but not really workable on a street rig. Unless you like to clean oil film off everything that is.