somender singh grooves on geo metro xfi
 

http://somender-singh.com/content/view/133/37/

look how many mpg's he's getting!

60-67 mpg and he doesn't even have a boattail!

60mpg at 60mph isn't too hard in the mk4 Jetta TDIs either. I avg'd better than 60mpg on a trip from central CA to eastern WA last December... no engine modifications, and only a grill block.

You can see it in my fuel log... when I'm the one driving, I can get pretty high commute mpgs even with stop & go driving.

Further aero mods would help as well... :)

test results test description
 

singh groove testing in a G10 geo metro engine
here is a PDF with detailed testing and test results using singh grooves in a g10 3 cylinder geo metro engine , scroll to the end for the tables including bsfc tables
one groove and no compression increase by surface cutting the cylinder head , so better values are attainable
in a perfect world