Originally Posted by bwilson4web

I notice Popular Mechanics seems very pro-diesel and did a report on the VW Polo:

Another manual transmission auto body part vehicle being compared to the automatic Prius.

Popular Mechanics also likes the Jetta diesel:

(Both photos come from Popular Mechanics web site.)

I notice these Popular Mechanics high mileage claims occur on the highway and not from the EPA test protocols. Any idea about why that may be the case?

One of the reasons I prefer the EPA test protocols is all vehicles follow the same driving profile in well defined, standard conditions. It is a vehicle test that can be reproduced by anyone.

Bob Wilson

Originally Posted by kerpal

What kind of EPA test do they conduct??

Originally Posted by bwilson4web

Hi,

My question was rhetorical since the EPA tests are well defined at their web site, fueleconomy.gov

Over time, I've noticed diesel advocates make sure their 'tests' includes these key features:

• diesel tests use manual transmission vs. hybrid automatics
• diesel tests at speeds of at least 75 mph (not using an HCH)
• diesel tests in cold weather, the closer to freezing the better (and no radiator block on the hybrid)

My studies indicate that Toyota (possibly Honda) could close down these faux, high-speed tests by providing the following:

1. high-speed transmission lock-up - in theory a mechanical brake on MG1 could convert the transmission into a fixed gear unit at high speeds. This would eliminate the MG1-MG2 energy flow needed to balanced the engine torque.
2. radiator block - an automatic system that blocks the front air inlet to reduce drag and preserve heat, especially in cold weather.

Now I cruise at 65 mph which delivers at least 52 MPG all day long on a standard 70F day. In fact, down to 35F, my 65 mph highway speed on cruise delivers at least 50 MPG without fail.

Bob Wilson