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The donkey CRX · 07-15-2015, 08:13 PM

Thanks for your kind words, Its great when others "connect" with what we are trying to accomplish.

Here is the list of modifications that are listed on my fuel log on this site. Most of these changes were all made at the same time and I don't have "documented" MPG improvements for each modification separately. But I do have a lot of experience with the results of these changes with 3 other Honda cars. 88 CRX, 95 VX, and the red 92 VX that had all of these same modifications done prior to putting them on the white 94 VX.

So here are the major modifications and my opinion of the MPG benefit of each:

14 X 5 1/2 HX wheels with Bridgestone RE 92 low rolling resistance tires. 7 or 8 MPG improvement over "regular" 13 inch tires.

Fuel pump "kill switch". 10 to 12 MPG. This is what I use to make EOC (engine off coasting) much easier. I am able to coast without using any gas between 17% and 20% of the total miles of my daily commute.

Alternator delete. 5-6 MPG. Because of the high up front cost of this modification, you may never recoup your cost with gas savings, but this modification also allows me to EOC at any time (night, winter, etc) without over working a regular starter battery.

Pre-heater for oil and water, 3-4 MPG. This mod really works in the winter, but also lowers the wear and tear on the engine all year long.

Next would be all the aero mods we did. Again the individual MPG numbers are my opinion, but I am very confident of the total MPG benefit.

Lowered car by 2 inches. 3-4 MPH. I was totally surprised by the improvement we saw with this modification. There seems to be a lot of doubt if this helps at all. I think it helped by lowering the "frontal area" and the amount of air that gets under the car. The downside is the rougher than normal ride quality that is not for everyone.

Adjustable grill block and filling of the fog light holes, along with the smooth transition to the belly pan by using an aftermarket spoiler. 3 MPG.

3/4 belly pan with rear diffuser 3-4 MPG

Larger than stock Kammbach 2 MPG

Delete of stock outside mirrors and addition of one small "moto" drivers side mirror. 1-2 MPH

Side skirts between the front and rear wheels. 1-2 MPG

Adjustable WAI (warm air intake) It's hard for me to put a MPG number to this mod, but I know it helps warm up the engine on start up and by keeping the intake air around 130 degrees I am convinced the computer leans out the fuel enough to improve MPG

Hand throttle. <1 MPG. The main reason I installed this was to allow me to rest my ankle and leg during my commute (54 miles) and to act as a "manual cruise control" for long trips. It would only help MPG by the amount of time it was used to precisely control the throttle.

Filled all gaps in front between the fenders, hood, bumper and headlights. <1 MPG. I can't measure any benefit from this modification, but I don't think it hurts MPG either.

Hope this helps. Remember, your mileage my vary from these numbers.

07-15-2015, 08:13 PM	#77 (permalink)
The donkey CRX Master EcoModder Join Date: Feb 2013 Location: TN Posts: 300 MULE VX - '92 Honda civic VX Team Honda 90 day: 92.6 mpg (US) White 94 VX "Show Car" - '94 Honda Civic VX VX 90 day: 79.92 mpg (US) The Walrus - '02 Honda Insight base Gen-1 Insights 90 day: 100.88 mpg (US) Thanks: 399 Thanked 564 Times in 189 Posts	Reply to Rwhyde Thanks for your kind words, Its great when others "connect" with what we are trying to accomplish. Here is the list of modifications that are listed on my fuel log on this site. Most of these changes were all made at the same time and I don't have "documented" MPG improvements for each modification separately. But I do have a lot of experience with the results of these changes with 3 other Honda cars. 88 CRX, 95 VX, and the red 92 VX that had all of these same modifications done prior to putting them on the white 94 VX. So here are the major modifications and my opinion of the MPG benefit of each: 14 X 5 1/2 HX wheels with Bridgestone RE 92 low rolling resistance tires. 7 or 8 MPG improvement over "regular" 13 inch tires. Fuel pump "kill switch". 10 to 12 MPG. This is what I use to make EOC (engine off coasting) much easier. I am able to coast without using any gas between 17% and 20% of the total miles of my daily commute. Alternator delete. 5-6 MPG. Because of the high up front cost of this modification, you may never recoup your cost with gas savings, but this modification also allows me to EOC at any time (night, winter, etc) without over working a regular starter battery. Pre-heater for oil and water, 3-4 MPG. This mod really works in the winter, but also lowers the wear and tear on the engine all year long. Next would be all the aero mods we did. Again the individual MPG numbers are my opinion, but I am very confident of the total MPG benefit. Lowered car by 2 inches. 3-4 MPH. I was totally surprised by the improvement we saw with this modification. There seems to be a lot of doubt if this helps at all. I think it helped by lowering the "frontal area" and the amount of air that gets under the car. The downside is the rougher than normal ride quality that is not for everyone. Adjustable grill block and filling of the fog light holes, along with the smooth transition to the belly pan by using an aftermarket spoiler. 3 MPG. 3/4 belly pan with rear diffuser 3-4 MPG Larger than stock Kammbach 2 MPG Delete of stock outside mirrors and addition of one small "moto" drivers side mirror. 1-2 MPH Side skirts between the front and rear wheels. 1-2 MPG Adjustable WAI (warm air intake) It's hard for me to put a MPG number to this mod, but I know it helps warm up the engine on start up and by keeping the intake air around 130 degrees I am convinced the computer leans out the fuel enough to improve MPG Hand throttle. <1 MPG. The main reason I installed this was to allow me to rest my ankle and leg during my commute (54 miles) and to act as a "manual cruise control" for long trips. It would only help MPG by the amount of time it was used to precisely control the throttle. Filled all gaps in front between the fenders, hood, bumper and headlights. <1 MPG. I can't measure any benefit from this modification, but I don't think it hurts MPG either. Hope this helps. Remember, your mileage my vary from these numbers.