Quote:
Originally Posted by Taylor95
On forums I've heard people say that the roller rockers would give you an easy 1 mpg. They are expensive though.
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That claim sounds highly suspicious. Motorcycles and a lot of high performance cars use bucket lifters. A roller rocker's pad still slides on the valve stem, and the roller is a plain bearing, so the friction is on the same order of magnitude (as opposed to e.g. roller bearing vs hydrodynamic journal bearing, where you have a 10x decrease).
Higher compression ratio definitely helps a lot since you're only at 8.8 if I'm reading specs on the internet correctly. If you want to mess with cams, going higher duration while keeping overlap the same will reduce torque but increase part load efficiency.