Quote:
Originally Posted by Frank Lee
We are aware of the hot rod mods. Biggest problem is, much of the hot rod stuff makes more power by moving the rpm range higher. We can't utilize that for greater fe. The other stuff that doesn't necessarily raise the rpm range has been investigated and found in some cases to do something good and in some cases not, but nothing really gives a radical improvement.
|
I wouldn't think you'd get a radical improvement since the main focus of the OEM's has been meeting the CAFE regs. You just worry about the ounces and the pounds will take care of themselves. However, let's face it, 90% of engine advancements came from racers, not car manufacturers (forced induction, fuel injection, roller cams, etc) and more recently, GM has adopted the aforementioned roller rockers as stock on their LSx engines.
I would think one thing you can do is to improve the precision of your engine. Install flow matched injectors and tune the slop out of the stock program, for example. Something else you might think about is using smaller injectors - smaller injectors would provide more homogenous air/fuel mixture at part throttle speeds. You might need to put some sort of restriction in your air intake, or tune your computer to a lower redline maybe, to keep from going lean at wide open throttle, though.
Maybe porting your heads. Not the intake so much, but optimizing the exhaust port for max low lift flow would help reduce pumping losses.
OEM's have to meet a price point. But many folks are looking for high mileage regardless of cost - anyone who buys a hybrid, for example, fits that description. So if you look at this the same way a hotrodder looks at going fast, that is, he who improves his mileage the most wins, there are lots of things you can do to improve mileage that don't necessarily make economic sense (boat tail).