Choosing EPA Ratings for Highly Modified Automobiles

[DracoFelis]

Originally Posted by SVOboy

I took what I had and improved upon it, and that doesn't show currently. Dracofelis, our newest member, PM'd me last night asking my EPA rating was so crappy, because there's no way to tell.

More accurately, I was curious why a 1991 CRX DX (which just so happens to be my model car as well) was being listed with the HF (a much higher EPA version of the CRX) EPA ratings. The main reason I was asking, was to make sure I was using the correct EPA ratings for my car (since the owners manual for my CRX doesn't list the EPA).

Of course, when SVOboy told me that he had moded his DX with HF parts, it made a little more sense to me. But, since he didn't start with a HF, nor did he replace all the CRX with HF parts, I still think using the HF EPA in his case is a bit of a "pessimistic" way of looking at things.

BTW: If anyone is wondering, SVOboy said to use the FE.gov site for my EPA. So FWIW this is the entry that most closely matches my car:
http://www.fueleconomy.gov/feg/noframes/7472.shtml

[SVOboy]

Holy crap, they actually got a picture of a crx!!! haha, it's always been the civic sedan. yeah, that's the dx though.

[ketel0ne]

I vote for whatever it takes for the site to include more members and promote gas savings of all kinds. If we are too focus on aeromods and mechanical transformations the average commuter who really needs to change their driving habits and buy a scangauge will be turned off.

While I am willing to try anything once on my 1996 Geo, I doubt I will make any aero mods or motor changes to my Yaris during the first 3-5 years.

So the question becomes to want the political party of gassavers.org to be a party of inclusion or a party of elitism.

Some times the vision of a goal blocks the success of a mission.

[SVOboy]

I have 0 idea what you're talking about. People who are just trying to improve through driving technique don't have to worry about this at all, they should be happy, we're just wanting to make a better basis for comparison, if one exists.

I like everyone on this site understands that driving modifications are greater than physical modifications, but that does not mean we cannot pursue both, I think.

[ketel0ne]

I think you overestimate the readers of this site.

If it affects the top ten list it affects the readers and all the people tracking. Correct?

[Matt Timion]

Originally Posted by MetroMPG

As for vehicle mods, if you take a CX hatch and put a VX drivetrain in it, I think you should use VX figures in the gaslog. You haven't done anything the Honda engineers haven't tried already.

But if you create a combination of drivetrain/body components that simply doesn't exist, or improve the vehicle in ways that the engineers didn't originally attempt, then stick with the original EPA figs, and get points for trying harder than the manufacturer.

This actually makes the most sense to me. I think in the end, however, it's going to be up to the user to decide what they put as their EPA ratings. I have no desire to police the gaslogs to ensure accuracy.

The way I see it my car was never created by Honda:

• four door sedan
• d15z1 engine
• CRX HF transmission
• air conditioning
• power steering
• VX rims
• 2200lbs

There isn't a vehicle that even comes CLOSE to that. The same can be said for CRX HF that is outfitted with a Civic VX engine. It's a CRX HF with a better engine, one that had not been "invented" (or at least released to the public) yet.

[Matt Timion]

Originally Posted by ketel0ne

I vote for whatever it takes for the site to include more members and promote gas savings of all kinds. If we are too focus on aeromods and mechanical transformations the average commuter who really needs to change their driving habits and buy a scangauge will be turned off.

While I am willing to try anything once on my 1996 Geo, I doubt I will make any aero mods or motor changes to my Yaris during the first 3-5 years.

So the question becomes to want the political party of gassavers.org to be a party of inclusion or a party of elitism.

Some times the vision of a goal blocks the success of a mission.

This is why I think that it will always come down to the user. The best way to include everyone is to let them choose their own path.

[krousdb]

Originally Posted by MetroMPG

Ahem.... rear wheel skirts, smooth wheel covers, tire deflectors, front wheel arch gap fillers, partial boat tail... ahem....

My average speed is 35 MPH. How much do you think that stuff would get me? Certainly not 80-100 like you.

The point of a partial boat tail is lost on me, at least on the hatchback. There is already a tail / spoiler on the back which I assume is there to promote separation of the flow.

[krousdb]

Originally Posted by MetroMPG

Dan and I have already concluded (if you don't mind me speaking for you, Dan) that it's harder to beat the EPA rating in our purpose-designed "efficient" cars which have been optimized (some more than others) by the manufacturers to perform close to their maximum efficiency in the EPA test cycles, with the result that they "peak" sooner than other cars in % over EPA comparisons.

I don't mind at all Darin and I agree wholeheartedly.

Originally Posted by MetroMPG

As for vehicle mods, if you take a CX hatch and put a VX drivetrain in it, I think you should use VX figures in the gaslog. You haven't done anything the Honda engineers haven't tried already.

Agreed!

Originally Posted by MetroMPG

But if you create a combination of drivetrain/body components that simply doesn't exist, or improve the vehicle in ways that the engineers didn't originally attempt, then stick with the original EPA figs, and get points for trying harder than the manufacturer.

Agreed, as in Matt's case. But for Ben, swapping from auto to manual creates a match for an existing car, so a 5 speed CRX DX would be the closest, although the 2.95 FD gives him HF type credentials. But Ben also has MFPI and the CX IM/TB. So no reasonable match I would agree.

And more food for thought....
What happens when Ben swaps his head to B8 or the engine entirely? What does he have now? Basically he has a CX with taller gearing, lower Cd and less weight and fewer seats. What would you do in that case?

[zpiloto]

I think what your car started out as originally as far as EPA values go.

I think a mod is a mod. Need to leave egos at the door. Look at the pickup that been aero modified. If you have the ability, skills and money have at it. I don't have any of those but strive to get the best I can for the money I'm willing to spend. In the grand scheme of things that what matters. I think that most people that come here won't be swapping engines and transmissions to get the max EPA out of it but will be looking for ideas that can help them save a little gas.

Top ten is the best of the best and people will see what type of cars or modifications they will have to do to get there.

If the top ten is really an issue just add categories: Modified, diesel,manual, standard, hybrid, electric etc that way we could all be in the top ten.