Hello, I happen to be a member of the Camry Hybrid forum since I have an 07 TCH as well and I recently came across the following post where the author contends that the sweet spot RPM range mentioned in the "Tao of HSI" document doesn't match up with the BSFC for the 2010 engine. I quote: "Also the rpm ranges in the article do not seem to match up to the Prius BSFC maps. The author keeps talking about the maximum efficiency being in the 1100 to 2100 rpm range. I would suggest for the 1.8L Prius engine it is more accurately from about 1100 to 3100 rpm, and really does not start to drop off significantly until you are over 4000 rpm. This would indicate that the maximum efficiency point is likely to extend well beyond the "green" zone shown in this graphic." Best Hybrid Driving Technique for Maximum Fuel Efficiency? - Page 7 - Toyota Nation Forum : Toyota Car and Truck Forums I am trying to understand what is amiss here. Thanks.
Yes, I also noticed that the ECO zone limit is roughly at 2000 RPM (varies some depending on speed) while ICE is super efficient up to 3000 RPM or more. I'm thinking there are increased tranny losses when you exceed the ECO zone limit, but that's purely a guess.
