Not Much You Can Do (to an engine to raise efficiency... o rly?)

[DAN]

THE FACT IS THERE IS NOT MUCH YOU CAN DO TO A MOTOR TO RAISE MPG. AND BE LEGAL. THEY BURN FEUL AT A %99+ to make heat. its the waste heat that needs to be used. in reality we can't do anything about it. the makers used tuber chargers and but they cost more. FOR US THE FEDS CALL IT TAMPERING. AND WITH THE OPEC 2 COMPUTER ITS VERY HARD. THATS WHAT THE FEDS WANTED. I ALWAYS MESSED WITH MINE BUT NOT NOW. IT SETS OFF THE CHECK LIGHT. THERE IS ONE THING THAT MAY WORK. I KNOW IT WORKED BACK IN CARB. DAYS. BUT I HAVE NOT FOUND THE SPACE NEEDED IN NEW CARS. AND ITS NOT THAT MUCH.

[DAN]

Ord Ord Not Opec

[Frank Lee]

Hey Dan, you don't need to yell.

Engineering is compromise, pure and simple. There are things people can do to improve mpg if they are willing to give up something in another arena.

[DAN]

Engineering is compromise, right. too few see that. but the law says what can be done.

[roflwaffle]

Peak efficiency varies little from engine to engine, and I've seen no laws against changing gearing.

[RH77]

Arrest the car dealers! They're installing engine block heaters in vehicles!

RH77

[Daox]

Dan, you are correct that there isn't a lot you can do to an engine to increase its effeciency. At least not at the level most of us are able to do. However, there is a lot of things you can do to the vehicle that will increase mileage. I think if you read what is posted here, very little is actually engine oriented.

Also, in this day and age, piggyback fuel/ignition computers for OBDI & II computers are not expensive. They are much less than buying a new carb (however, much more than just retuning a stock carb).

[8307c4]

One small way in which engine heat can be harvested for gain is to park the car inside the garage in winter, and outside in the summer. That is, so long the garage connects directly to the house the heat from the engine can and does warm the air inside this garage to a point and it does make a small difference in the home's cooling and heating efficiency.

[trebuchet03]

THE FACT IS THERE IS NOT MUCH YOU CAN DO TO A MOTOR TO RAISE MPG.

Sure there is - you answered it yourself... Don't do much to the motor The less work it has to do - the less you can use it, and increase your mpg

That aside - most of us know this already... Which is why reducing friction (aero and mechanical) is a big deal and the focus of many of modification

[Coyote X]

I say there is a lot of stuff that can be done to the motor, just depends on the laws in your area

My list of engine mods:
* Screen type Windage Tray and Crank Scraper
* Shaved head 0.040″ for 10.5:1 compression
* Ported and polished head
* Cam Advanced 3 degrees
* Ignition timing at 6 degrees
* 2″ exhaust with free flowing muffler
* Convert to a 4 wire Oxygen Sensor
* Converted again to an Innovate LC-1 wideband Oxygen Sensor
* MSD 6AL Ignition Module and Accel Supercoil
* Swapped out stock computer for a Megasquirt computer

All of those are legal in my state and each of them helped mileage, some more than others. The exhaust probably is the worst, cam/ignition timing is prob best. I lost the factory exhaust when I hauled the car home so I didn't have any way to test that mod.

There is a lot you can do to an engine that won't trip an obd2 error code so really it is perfectly possible to tune any engine to get a bit better mileage.