Kiddo
You're serious bro?!
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So i was reading an article on Autospeed about engine designs, and came across something called the BMEP calculation. Below is a snippet from the article explaining what it is and how its worked out;
OK, so how do you use this wondrous formula? Keeping it all metric, it looks like this:
BMEP = kW x 1200/litres x rpm
So i thought I'd calculate the BMEP for popular holden engines, as an unbiased comparison on their design.
RB30E VL Commodore - 114 kW at 5,200 rpm - 8.8
RB30ET VL Commodore - 150 kW at 5,600 rpm - 10.7
3.8 Buick - 125 kW at 4,800 rpm - 8.2
Ecotec - 147 kW at 5,200 rpm - 8.9
5.0 V8 (VS HSV Clubsport) - 185 kW at 4,800 rpm - 9.25
L67 Supercharged - 171 kW at 5,600 rpm - 10.4
LS1 (VT) - 220 kW at 5,000 rpm - 9.2
LS1 (SV300) - 300 kW at 6,000 rpm - 10.5
LS2 6.0 (HSV) - 297 kW at 6,000 rpm - 9.9
LSA Supercharged 6.2 - 430 kW at 6,000 rpm - 13.8
BMEP refers to the average pressure that acts on the piston during the engine’s four strokes. The higher it is, the more the design has been optimised. And the key thing about BMEP is that it takes into account engine rpm, engine volume and engine power output. It’s the only equation to use when comparing engines from the perspective of saying which is more highly developed. It doesn’t matter whether the engine uses pushrods; 2 valves per cylinder, 4 valves per cylinder or 5 valves per cylinder. It doesn’t matter whether the engine revs to 8000 rpm or 1500 rpm. You can use the equation to directly compare any 4-stroke engine, whether it’s 660cc or 5.7 litres
And you can even use it to compare naturally aspirated and forced induction engines. The BMEP figure for a forced induction engine will have a major advantage, but it’s still a valid method of comparison.
OK, so how do you use this wondrous formula? Keeping it all metric, it looks like this:
BMEP = kW x 1200/litres x rpm
So i thought I'd calculate the BMEP for popular holden engines, as an unbiased comparison on their design.
RB30E VL Commodore - 114 kW at 5,200 rpm - 8.8
RB30ET VL Commodore - 150 kW at 5,600 rpm - 10.7
3.8 Buick - 125 kW at 4,800 rpm - 8.2
Ecotec - 147 kW at 5,200 rpm - 8.9
5.0 V8 (VS HSV Clubsport) - 185 kW at 4,800 rpm - 9.25
L67 Supercharged - 171 kW at 5,600 rpm - 10.4
LS1 (VT) - 220 kW at 5,000 rpm - 9.2
LS1 (SV300) - 300 kW at 6,000 rpm - 10.5
LS2 6.0 (HSV) - 297 kW at 6,000 rpm - 9.9
LSA Supercharged 6.2 - 430 kW at 6,000 rpm - 13.8