RWD cars with good MPG? (Looking for a highway commuter)

[wdb]

Originally Posted by Grinder74

turbo makes it a little harder to get up to speed without drinking gas.

Congrats on the car. Turbos improve efficiency, that's why many many new cars, SUVs and even pickup trucks have turbocharged engines.

[serialk11r]

Originally Posted by Daschicken

The gearing is just too short for good MPG in the S2000.

Actually, the S2000's aerodynamics are bad enough that the gearing is probably not the biggest problem (lol).

Newer engines have shown how effective EGR is at increasing part load fuel efficiency. The S2000...has none. It has no cam phasing either. The low load efficiency as a result is BAD.

@OP congrats on the Cruze, you can tune the ECU to improve efficiency under boost at the expense of momentarily higher EGT (probably not a problem since you're not racing the car).

[Daschicken]

Originally Posted by serialk11r

Actually, the S2000's aerodynamics are bad enough that the gearing is probably not the biggest problem (lol).

Newer engines have shown how effective EGR is at increasing part load fuel efficiency. The S2000...has none. It has no cam phasing either. The low load efficiency as a result is BAD.

Drag coefficient of .33 with the top up. I think I heard about the top down increasing the Cd by 25%, but don’t quote me on that. That would raise the Cd to 0.41. 70 mph I’m pretty sure was around 4000 RPM. No EGR huh? I never noticed. Now I’m really wondering how Honda got these things to pass emissions. It would blow a cloud of smoke and smell awful when accelerating full throttle last VTEC. Ours never needed emissions work, but it is very possible that the previous owner did some trickery.

I also noticed that the S2000 was about as slow as my I4 accord up to 6000 RPM, then they switched roles as the S2000 screams ahead and the accord lags behind.

[Tahoe_Hybrid]

Originally Posted by Daschicken

Drag coefficient of .33 with the top up. I think I heard about the top down increasing the Cd by 25%, but don’t quote me on that. That would raise the Cd to 0.41. 70 mph I’m pretty sure was around 4000 RPM. No EGR huh? I never noticed. Now I’m really wondering how Honda got these things to pass emissions. It would blow a cloud of smoke and smell awful when accelerating full throttle last VTEC. Ours never needed emissions work, but it is very possible that the previous owner did some trickery.

I also noticed that the S2000 was about as slow as my I4 accord up to 6000 RPM, then they switched roles as the S2000 screams ahead and the accord lags behind.

VVT engines improve the emissions output (WAY less) 100% of all VVT engines have no EGRs.. 50% less no EGR required that is why most of the are LEV2 or SULEV etc.. mine with VVT has LEV2 rating while a non VVT has a LEV rating

[RedDevil]

The second gen Honda Insight (ZE2) has EGR and VTEC, so it is possible to have both. Ultra low emissions (besides CO₂) to boot.

[Vman455]

Originally Posted by RedDevil

The second gen Honda Insight (ZE2) has EGR and VTEC, so it is possible to have both. Ultra low emissions (besides CO₂) to boot.

As well as the Prius since 2010.

[serialk11r]

Dual VVT allows internal EGR but not LIVC. External EGR allows intake timing to be retarded while diluting the charge for very high efficiency down to the 50% load range.

You don't need EGR to pass emissions, 3 way cats do their job very well. EGR just makes it a little easier by reducing NOx production.

Also the S2000 is definitely not .33, it's got a tall windshield and short tail like a Miata, it's probably like .37.

[cRiPpLe_rOoStEr]

Originally Posted by wdb

Turbos improve efficiency, that's why many many new cars, SUVs and even pickup trucks have turbocharged engines.

Turbos alone won't do a miracle. Direct injection preventing the need for an enrichment of the AFR might also be considered, no wonder it became prevalent in newer turbocharged gassers.