At some point in the early 60's GM switched most V8's from a road draft setup to the PCV setup. On my '61 Impala I just stuck breathers in each valve cover and it would idle so poorly and have no power off idle, after doing research I decided to put the PCV back on and it fixed all of the problems I was having. I'm a firm believer that all engines should have a PCV setup, I will be adding one to my 348 W motor's valve cover when I rebuild it.
You touched on what I understand to be the negatives... the venturi effect means road draft tubes are ineffective while stopped and at low speeds. There's also the issue of it not actually being an emissions system, it just dumps the excess pressure and whatever is suspended in the air into the atmosphere...I wish mine card still had the road draft tube and no emissions crap, no fuss, no muss, no exhaust gas introduced into the induction system. And a 1" steel pipe can relieve crankcase pressure faster than a rubber hose connected to a spring loaded valve. If we're talking stock setup, the early 60s 283/348s and 194s had road draft tubes and the carbs were not setup with a vacuum takeoff for a reason, engine was designed to run on straight gas/air and not to suck oily crankcase gases especially when the chokeplate is closed in cold weather. System required only a periodic cleaning of the reusable valve cover breather. These engines cannot run correctly with a breather in each valve cover, the blowby gases will choke and dilute the mixture in the combustion chambers.....no vacuum source and pressure across both breathers so the gases cannot escape the crankcase effectively. Road draft tubes work on a venturi principle where air moving under the car across the end of the tube creates a partial vacuum so fresh air enters the breather and crankcase gases get sucked out the end of the road draft tube. My 194 was a smoker, never saw the blowby gas when moving, but when stopped for a light the smoke from the tube came out of the passenger wheel well, more than one date and adjacent cars had remarked the car was on fire.
For my 2 cents the road draft tube meets 60's emissions so why not reinstall it and run only on gas and air, and not burned crap.....might even increase gas mileage.
I think I'd soil myself if my car rolled a foot after engaging park... My '14 only rolls a couple inches which seems normal to me based on the cars in my signature. If it rolled a foot I'd definitely bump a car in the parking lot.Haven't measured the roll, but it seems around a 10 to 12 in. Which, seems excessive to me. But the young service man at Jerry's Chevy dealership said it was normal.
Will do a little research.
A poorly designed PCV system doesn't render all PCV systems a bad idea. An ideal setup will allow oil mist to separate out and just carry the vapors, thus minimizing oil collection in the intake tract. Putting it back into the intake is a necessity since you need the vacuum source in the first place, and the fact you can combust the nasties instead of breathing them in is a nice side benefit. The PCV isn't the only source of oil in the intake - depending on ring condition and reversion between the cylinders, you'll often see some oil build up just from blowby - I've seen the top ends of race setups that ditched the PCV and just ran a breather and you still get dirty intake ports.Agreed, a properly functioning PCV system is a good thing because it removes corrosive by products of combustion......but what does it do with them?.....it stuffs them right back into the engine where it can crap up the induction system. Sort of like washing the car and dumping the bucket of dirty soap water into the washing machine instead of onto the driveway.
A vacuum pump to keep negative pressure in the crankcase is an excellent idea, but importantly what does it do with the corrosive crap coming out of the exhaust side of the vacuum pump? Because if it throws it back into the induction system it negates the idea of increased vacuum in the crankcase. If it dumps it into the atmosphere, which makes more sense, it is in reality acting on the same principle of a motorized road draft tube, albeit more efficient.
Doesn't seem to make any sense to run a racing engine with a PCV system or an EGR for that matter.
Yea it's not an actual PCV valve like we are used to, it's really just controlling flow through the orifice, enlarging them slows down the gas which helps the suspended solids settle out rather than get sucked into the manifold.Is this "PVC" valve in the pics open inside? I seen a video where they drilled out the holes a little for better flow. I pulled mine this past weekend and it was all gummed up. I cleaned her up and opened up the holes on both ends.
Have the same problem this is the worst ever vehicle gm has ever produced.Been all over the net, U tube, etc.
Nobody has had a seized valve..............Why Me??
But, that thing is coming outta there even if I gotta put a torch on it........and I gotta half a mind to do it.
The BW...IE: Beautiful Wife agrees.........I gotta half a mind.
How bout the "Unsafe at Any Speed"......IE: Corvair?Well I don't know about that. Remember the Vega? Yes this vehicle has it issues but it is far from being the worst. I am on my second Lambda. First a 08 Outlook, WavePlate, P.S. Pump and Rack, waterpump, Plugs at the first 100K, A couple of Purge Valves, 2 sets of Tires, Stabilitrack, Milkshakes, Throttle Body clogged PCV, MAF sensors, 212K I can't reall complain too much. I now have a Certified 2015 Enclave,60K no problems so far.
The '60-'63 Corvair certainly had a problem with the swing axle design that pivoted at the transaxle and could, under certain conditions, cause the axle to "tuck". Ralph Nader's book, unfortunately, painted the '64 and later Corvair's with the same brush. However, the modified design that incorporated universal joints at the out-board end of the axle shaft enable the wheel to remain in a vertical alignment even when the suspension was compressing or rebounding. It was a design very similar to the independent suspension incorporated in the '63 Corvette--but you never hear of them having a safety issue due to rear suspension design. Just my opinion, but I think the '64 and later Corvairs were an excellent car--especially the Corsa with the turbo. Fun cars to drive!How bout the "Unsafe at Any Speed"......IE: Corvair?