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Author Topic:   Lifter Valley Vent Tubes
posted March 05, 2004 03:32 PM
Will using these vent tubes restrict oil from getting to the cam lobes? I can understand that it helps crankcase ventilation get up to the uppper part of the motor and decreases windage around the cam. But I was just wondering if the cam lobes and the bottom of the lifters will receive an adequate amount of oil by using these. Should these only be used with a roller setup and not a tappet?

posted March 05, 2004 04:33 PM
They are most often reccomended for roller setups but you can use them with solids as well. Most of the oil on the cam is thrown off the crankshaft anyway. Thats why you dont want to let them idle too slow because it wont sling enough oil around to keep the cam covered.

posted March 05, 2004 11:15 PM
Well, I plan on using a crank wiper so as far as slinging the oil off the crank goes.......I dont think there will be much to throw up to the cam, if in fact this is what actually happens. I doubt I'll use the vent tubes. Something about these worries me.

posted March 06, 2004 06:36 AM
I've been using them for 8 years or so now. No problems so far. Solid cam, restrictors, windage tray. The only cam wear problem I've had has been on the dist. gear. After about 80 nites or so, its getting pretty thin. I do break in the cam with lite springs thou.

rico 08
posted March 06, 2004 03:53 PM
Popular hot rodding did a test in the engine masters challenge for valley vents vs none and the dyno showed no gain.

posted March 06, 2004 07:19 PM
Most of the oil that is slung on the cam from the crank will come from the rods. I have run them just to keep oil off the bottom of the intake. It may not help but it sounded good to me!

Ego Racing
posted March 08, 2004 01:09 PM
They may not give more power but they do get the oil to the pan faster. If the oil gose through the center holes it has to touch the cam, crankshaft/rods before it can get back to the pan to get pumped back around where the rear and front holes dump to the pan.
Also how many RPM's did they dyno it at and did they pull acceleration tests? Oil adds weight to the crankshaft and can cause an out of ballance condition, by it's nature it will hold on and run to the farthest diameter before it comes off so it will add weight to the outside weights. The added weight of the oil will also slow down acceleration of the rotating assy.

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