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Old 03-18-2015, 02:30 PM   #270 (permalink)
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gueff - '19 Mercedes Benz A250 4MATIC AMG
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Originally Posted by P-hack View Post
not quite a complete picture, but very interesting all the same.

green looks like 265gm/kwh and red is ~294 @ 1800rpm

I wouldn't be suprised if there were more efficiency at a higher rpm with a little more than %25 throttle, but yah, pulls are $$$

I don't have the brain cells to turn it into a bsfc map at the moment though. Part of the issue is that tps isn't load, but is a function of rpm and load.

Do you have more detailed data in table format by any chance?

edit: I think this is the sort of reasonable first step anyway based on the graph, not exactly sure how to translate to load instead of tps, some rpm based scaling and interpolation I guess.

re-expressed as tps/rpm in gm/kwh
40	285	280	282	276	278
25	272	266	265	269	275
20	272	270	271	278	285
15	288	289	294	308	324
	1400	1600	1800	2000	2200
I will make a thread about this in general efficiency forum and post some more data:

also i'm not good at making charts. here is data from wider engine speed operations should you wish to make a graph (attached too). Vacuum and power should help you determine load.

Attached Files
File Type: xls fullrangedyno.xls (23.5 KB, 39 views)

Last edited by ever_green; 03-18-2015 at 03:33 PM..
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