PDA

View Full Version : Venting the crankcase



TR32
03-19-2012, 07:40 PM
I have seen and ran a block(2.3l) that had the crankcase vent hole plugged. I never had an issue with blow by. I have also ran one with the hole unplugged and had serious blow by through a breather and the valve cover breather. I have heard several different theories. So I am asking the brain trust, what is the best way to vent a 2.3 ford ministock engine? The low end rpm would be 68-7200 and high end would be 78-8000 depending on head and cam.

Milford Motorsports
03-19-2012, 09:23 PM
Run a piece of 3/4 heater hose from the stock crank case vent to a one gallon vented catch can.It's dirt cheap and allows you to keep track of how much oil is being vented out of the engine.

Dirtman29
03-19-2012, 10:52 PM
I use a PCV valve in the block hole (Autozone #1225, use black RTV silicone on it & let it dry overnight), then I attach a 3/8" rubber fuel line to the PCV, run it up the firewall, then use a small cone filter on the that end. Its cheap & it breathes just fine. Ive had the OEM oil separators fall out while racing, Ill never use them again.

mark41
03-20-2012, 09:31 AM
i plug it off and run an evacuation system to the header, i also run extra oil lines from the valve cover to the oil pan (-12 lines, 4 of them) to drain the valve cover and restrict the flow of oil to the cylinder head. that keeps the evac system from sucking oil out into the exhaust...just my .02 though....

TR32
03-20-2012, 11:52 AM
Isn't 4 lines a bit excessive? I would like to hear more about your system though. Does evacuating to the collector free up any hp?

mark41
03-22-2012, 12:34 PM
it is a scavenging effect to get the oil out of the valve cover area. all hoses go directly to the oil pan nothing drops down on the crankshaft. the whole thing started out as the evac system and when the exhaust smoked out the race track we had to figure out why. we made a plexiglass valve cover. one would be amazed to see how much oil is in the top of that little motor!!! yes it does free up something....

TR32
03-22-2012, 02:15 PM
Sent you a PM Mark.

84Dave
03-23-2012, 11:10 AM
If one wants/needs to observe what is happening, vacuum/pressure-wise, inside the engine under actual running conditions, attach a good sized boost-vacuum gauge to the dipstick tube via a rubber hose. Then mount the gauge in the 'pit, level with the driver's head on the left side. Easy to quickly monitor the gauge during practice sessions. -Dave-

Old Rob
04-14-2012, 08:36 PM
A lot depends on your rules. If no vacuum pump, vac u pan systems are allowed, the use the stock breather in the block and run a hose to an canister, with a breather on it, mounted high. We usually put them on the radiator support on the left side. Mounting it high will allow any oil to drain back. No breathers on the valve cover leave it sealed helps with oil drain back from the top. Thats where most of your oil goes.

double7
04-22-2012, 08:33 PM
I use a PCV valve in the block hole (Autozone #1225, use black RTV silicone on it & let it dry overnight), then I attach a 3/8" rubber fuel line to the PCV, run it up the firewall, then use a small cone filter on the that end. Its cheap & it breathes just fine. Ive had the OEM oil separators fall out while racing, Ill never use them again.

do you seal your valve cover off,or do you use a breather on it ?

Dirtman29
04-23-2012, 04:16 PM
do you seal your valve cover off,or do you use a breather on it ?My oil cap is vented also, 3/8" hose to a homemade catch can.