Brake Specific Fuel Consumption: A Really Useful Concept

[tasdrouille]

There's a very interesting article on BSFC over at Autospeed. It's a must read for anyone concerned about FE.

http://www.autospeed.com/cms/A_110216/article.html

[Daox]

Very good article. It cleared up a few things I had thought (and was wrong about).

[RH77]

Great find!

It seemed to explain quite a lot that remained unclear...

RH77

[PaleMelanesian]

I have. Pulse & Glide is the best way to take advantage of BSFC.

[tasdrouille]

CVT transmissions are based on this concept.

[Daox]

I just wish that manufactuers published this info! Its almost impossible to find BSFC charts for cars.

[PaleMelanesian]

I've been tempted to go out and make my own bsfc chart. Using the scangauge, do multiple runs on a flat level road. Start at 1000 rpm so and run up through the rpm range. One run at 5% throttle, one at 10%, etc... Rig up a video camera for review and chart out the Gallons / hour vs rpm.

or something like that...

[PaleMelanesian]

I used it to determine the optimum rpm and load for the pulse. I don't have a chart for my engine, but looking at several others, it seems that 1500-2000 rpm and about 3/4 throttle is the peak. That's what I use for the pulse part of my P&G. This way, when you do use the engine, it's at its best (lowest?) bsfc. And when you're not doing that, it's off.

It works, too. Grille block, tire pressure, scangauge, and P&G give me the numbers I have.

[MetroMPG]

I've changed my P&G technique since finding the BSFC map for my engine.

The little 3-cyl mill's peak efficiency is at a higher RPM than I'd been going to previously. It's basically centered just above 3k RPM, where I was aiming for low 2k range before. Makes for brisker acceleration.