VW Concept A (R&T)

[Joe_Black]

How is this like a Vehicross? It's super charged and turboed and it still gets only 148 horsepower? Natural gas must be really effecient! 148 HP with a 1.4L - comparing this to a Wankel Rotary NA Engine would be more acurate.

Natural Gas engines produce a bit more torque than regular gas engines, plus it's a more green fuel. A lot of farm tractor manufacturers offered Natural Gas versions as a less expensive alternative to their diesel models.

The Wankel isn't known for having very good economy and has always suffered from low torque, which is why it's pretty much never been seen in the 4X4 world.

[JAFO]

Natural Gas engines produce a bit more torque than regular gas engines, plus it's a more green fuel. A lot of farm tractor manufacturers offered Natural Gas versions as a less expensive alternative to their diesel models.

Ok, but taking 8 hours to half way fill up your car is rediculas.
http://www.usatoday.com/money/autos/...atgascar_x.htm

Still they were comparing a 3.5L 215 HP gasoline engine to a 1.4L 148 HP natural gas. Therefore I thought the comparison to a 1.3L 135 HP Wankel Rotary NA Engine was a more equal comparison.

And if natural gas is so good why does the VW need both a super charger and and turbo to get a meesly 148 HP?

The Wankel isn't known for having very good economy and has always suffered from low torque, which is why it's pretty much never been seen in the 4X4 world.

Naturally aspirated Rotarys yes, supercharged no. My 12AT 1.2L makes 200HP with 200 Ft/lbs of torque. A little off from our VX's 215HP 230 Ft/lbs of torque, but close considering it is a small turbo running 8 psi boost.

[Joe_Black]

Well, you have to admit that the kind of power they're getting out of a 1400cc engine is impressive and much of that's due to all that forced induction. The supercharger gives your low-end grunt while the turbo more or less provides pressure equalization from what I've seen of the VW trend with this set up.

Natural Gas set ups have different fills, so not all take that long to top the tank. The system listed in the article you linked is for the homeowner to use overnight and works on standard household gas-line pressure. Fill stations have much different equipment. From your article:

Filling stations that dispense compressed natural gas under pressure can fill a tank in three to five minutes.

We have a lot of local citrus growers that have converted many of their trucks (regular pickups) to LP and NG as it keeps the thieves at bay. They fill pretty quick, usually about 10 minutes and they've got sizeable tanks.

No doubt you can build torque with a Wankel, but this isn't what we've seen in most of the production rotaries. And at that you absolutely have to pressurize the engine. I've ran two RX-4's and have a 20B slated for use as the engine on a future homebuilt aircraft, which will be turbo-normalized.

[MZ-N10]

Ok, but taking 8 hours to half way fill up your car is rediculas.
http://www.usatoday.com/money/autos/...atgascar_x.htm

Still they were comparing a 3.5L 215 HP gasoline engine to a 1.4L 148 HP natural gas. Therefore I thought the comparison to a 1.3L 135 HP Wankel Rotary NA Engine was a more equal comparison.

And if natural gas is so good why does the VW need both a super charger and and turbo to get a meesly 148 HP?


Naturally aspirated Rotarys yes, supercharged no. My 12AT 1.2L makes 200HP with 200 Ft/lbs of torque. A little off from our VX's 215HP 230 Ft/lbs of torque, but close considering it is a small turbo running 8 psi boost.

technically speaking the 12a isnt considered 1.2, more like a 2.4L.


btw joe_black, u got any 20bs for sale?

[Joe_Black]

btw joe_black, u got any 20bs for sale?

Nope, but Australia is a good source with crate engines running around $4K - $5K last I checked.