Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post - VW quantifies MPG gain of 4- to 2-cylinder deactivation at 31 mph = +16 mpg

shovel · 04-07-2012, 04:11 PM

I don't see any big scary red flag on this, engine building is a pretty well established science and I trust VW's done their homework. They do a 10/100 powertrain warranty on the touareg, which would probably be appropriate for this too.

I'm curious though, wouldn't vacuum pull valves open a bit even if the cam wasn't pushing them? Especially with the help of manifold pressure on the other side of the exhaust valves..

04-07-2012, 04:11 PM	#23 (permalink)
shovel Master EcoModder Join Date: Feb 2009 Location: Phoenix Posts: 593 Thanks: 106 Thanked 114 Times in 72 Posts	I don't see any big scary red flag on this, engine building is a pretty well established science and I trust VW's done their homework. They do a 10/100 powertrain warranty on the touareg, which would probably be appropriate for this too. I'm curious though, wouldn't vacuum pull valves open a bit even if the cam wasn't pushing them? Especially with the help of manifold pressure on the other side of the exhaust valves.. __________________ Work From Home mod has saved more fuel than everything else put together.