how mods can equal better mpg...
I love how these cars are 21 years old, everyone build the hell out of them, then they say they get better than the mpg that was on the window sticker in 87
I think some people need a calculator.
It comes down to physics and chemistry...
There are *ONLY* two ways to increase the power output of an engine:
1. Increase the amount of air and fuel you can run through the engine in a given time frame. Most common methods:
a. increasing displacement
b. increasing boost
c. increasing peak engine rpm (lighter rotating assembly, etc.)
AND/OR
2. Increase the overall *EFFICIENCY* of the engine. Many of the oldest and most common combustion engine mods accomplish this:
a. improved, more complete combustion:
-- improved cylinder heads
-- better fuel management (more precisely calibrated carburation or more precise and faster responding computer controlled fuel injection)
-- better ignition (more precise spark timing control, hotter ignition spark)
b. reducing parasitic engine losses (roller valve train components, better engine oil, revised accessory drive ratios)
c. better than stock thermal management
-- cold air induction, larger intercoolers, aftermarket thermal barriers (heat wrap), etc.
-- vehicle weight reduction (lighter wheels, aluminum engine components, fiberglass body parts, etc.)
The mods I've listed above are just a few common examples I could think of. Other common mods like free-flowing headers, downpipes and exhaust systems as well as higher stall converters could be listed under both 1 and 2.
The bottom line is, by increasing the efficiency of an engine, you decrease the amount of fuel required to accomplish the same amount of work. In addition, one of the biggest advantages of turbocharging compared to any other means of increasing the power output of an engine is that when a turbocharged engine is under boost, you're getting the advantages from both #1 AND #2 above. However, when you're just cruising or accelerating moderately, you're *still* getting the benefits of #2 without the increased fuel consumption associated with #1.
Rob
