efficiency enthusiast here :)

[1337]

Hi all, I bought a Protege last fall, and I absolutely love it. When I graduated high school, my girlfriend and I went to different colleges, 570 miles apart. So, I needed a car that could efficiently and comfortable take me from Illinois to Oklahoma a couple of times per month.

So far, I've racked up 12k miles on the Protege, and I couldn't ask for a better car, for the money.

With just a few modifications, like a grill block, low rolling resistance tires, and some weight reduction, I've managed 35-40 MPG in the Protege. At current gas prices, I can do a 1140 mile weekend roadtrip (Illinois to Oklahoma and back) for under $50!

<3 my protege.

[FE3-323]

grill block???

[Turpro]

[1337]

grill block???

It's a really easy to reduce aerodynamic drag, so I use a little less energy to keep the car moving on the highway.

Also, the block stops bugs and dirt from getting in the radiator.

I blocked off the whole upper grill and about 75% of the lower grill. I leave the rest of it open to provide enough air to cool the engine. If I drove aggressively, I might leave more unblocked, but my Mazda is a 106 hp econobox, and I don't drive fast.

[worldhazard]

but my Mazda is a 106 hp econobox, and I don't drive fast.

around here there's an addiction. Modding your car, and going faster. also handling better. You'll catch it soon enough. No worries.

[1337]

around here there's an addiction. Modding your car, and going faster. also handling better. You'll catch it soon enough. No worries.

That's what my Miata is for.

The Protege is, short of a Geo Metro, the cheapest way to drive to Oklahoma and back on a weekend. I mod for efficiency, and I think of the Protege as a science project, not a performance car. I'm always testing new ideas for how to improve MPG.

When I'm on an 8 hour road trip, speeding is kind of a bad idea. I go past so many speedtraps, that it's just not worth it to speed.

[ArdaPro]

Around here we try to unblock more holes as possible and cut out more openings , but Welcome to CP anyways!!!

It's a really easy to reduce aerodynamic drag, so I use a little less energy to keep the car moving on the highway.

Also, the block stops bugs and dirt from getting in the radiator.

I blocked off the whole upper grill and about 75% of the lower grill. I leave the rest of it open to provide enough air to cool the engine. If I drove aggressively, I might leave more unblocked, but my Mazda is a 106 hp econobox, and I don't drive fast.

[XxaltezzaxX]

welcome.

[erwinz]

welcome..

[SgtRauksauff]

welcome!!

In my '90 323, I've swapped in the DOHC BP engine, but am still running 185/55-13 tires. No other mods, and I get around 37 @ 80mph fairly frequently. I don't take off slowly, and I only go slow around corners because the 13's have rather limited grip, lol! I think with some actual attention towards fuel economy, I could probably get at least 40 consistently. Like, some skirts for the rear wheels, some bubble-skirts for the front, and an undertray. A-pillar covers would probably help a bit, too. And removing my winter wiper-blades.

I've only managed to get 32mpg in my 90 Protege (still with the stock B8), but that's the 4WD with 85w140 oil in the rear and center diff, and snowtires still mounted. I think the slant-headlight front on my 323 helps with the mileage a bit, too, though.

What are you running for ignition timing? what do you run for tire pressure (and what size tires are you using?)

--sarge

[1337]

welcome!!

In my '90 323, I've swapped in the DOHC BP engine, but am still running 185/55-13 tires. No other mods, and I get around 37 @ 80mph fairly frequently. I don't take off slowly, and I only go slow around corners because the 13's have rather limited grip, lol! I think with some actual attention towards fuel economy, I could probably get at least 40 consistently. Like, some skirts for the rear wheels, some bubble-skirts for the front, and an undertray. A-pillar covers would probably help a bit, too. And removing my winter wiper-blades.

I've only managed to get 32mpg in my 90 Protege (still with the stock B8), but that's the 4WD with 85w140 oil in the rear and center diff, and snowtires still mounted. I think the slant-headlight front on my 323 helps with the mileage a bit, too, though.

What are you running for ignition timing? what do you run for tire pressure (and what size tires are you using?)

--sarge

I've considered an undertray, and rear wheel skirts, but I just haven't had time to do the work. I'm running 50 PSI in all four tires. I gradually worked my way up to 50; I ran about 35 when I first started being careful about fuel economy.

I don't usually go more than 70mph, and I only go 70 if it's the speed limit (as it is when I go through Missouri).

I haven't done anything to the ignition timing, though I know some efficiency gains can be had from advancing the timing. What timing do you run?

[Lex]

Here's another tip. Get an innovate wideband O2 sensor with a programmable narrowband output. Set the switchpoint to 15.5AFR instead of 14.7.

[1337]

Here's another tip. Get an innovate wideband O2 sensor with a programmable narrowband output. Set the switchpoint to 15.5AFR instead of 14.7.

Hmm, good thinking. I'd like to run leaner, but I understand that leaner combustion often results in higher combustion temperatures. Could this damage my engine?

I know some Honda engines (namely those in the manual transmission first generation Insight, the Civic VX, Civic HX, and Civic Hybrid) are able to switch into a "lean burn" mode. However, I've never heard of converting a non-lean burn Honda engine to run in lean burn.

Do you know of anyone who's tried to convert a Mazda engine to run with a leaner air/fuel mix?

[Lex]

Hmm, good thinking. I'd like to run leaner, but I understand that leaner combustion often results in higher combustion temperatures. Could this damage my engine?

I know some Honda engines (namely those in the manual transmission first generation Insight, the Civic VX, Civic HX, and Civic Hybrid) are able to switch into a "lean burn" mode. However, I've never heard of converting a non-lean burn Honda engine to run in lean burn.

Do you know of anyone who's tried to convert a Mazda engine to run with a leaner air/fuel mix?

Not while under low load - in other words at part throttle when the car runs in close loop. Once you go WOT, it won't listen to the O2 anymore. Running in the 15s is not an issue, I do so myself. Once you get too far - into the 16s, the car may start to miss and you'll notice.

This is not really lean burn - it's simply a little leaner than stoich. Your NOx exhaust emissions will go up a little as well.

[1337]

Not while under low load - in other words at part throttle when the car runs in close loop. Once you go WOT, it won't listen to the O2 anymore. Running in the 15s is not an issue, I do so myself. Once you get too far - into the 16s, the car may start to miss and you'll notice.

This is not really lean burn - it's simply a little leaner than stoich. Your NOx exhaust emissions will go up a little as well.

Interesting. What kind of oxygen sensor do you use for this? Guessing from your tagline, you use Megasquirt?

Is there any system that's cheaper than Megasquirt that could be used to lean out the mixture? I'm not planning to keep this Protege forever, and $200+ for a Megasquirt system is a lot of money for a 1-2MPG gain. It would take quite a lot of driving to recoup the cost of the Megasquirt system.