Just done dyno test after fitting 3.15 differential to my 328iM - here are the results...
Before differential fit...
RPM BHP KW NM BMEP
2000 60.7 45.264 216.1 9.699
3000 96.7 72.109 229.5 10.301
4000 135 100.669 240.3 10.786
5000 170.3 126.993 242.5 10.885
5500 184.2 137.358 238.5 10.703
6000 186.2 138.849 221.0 9.918
After differential fit...
RPM BHP KW NM BMEP
2000 60.8 45.339 216.5 9.715
3000 98.1 73.153 232.9 10.450
4000 135.4 100.968 241.0 10.818
5000 172.1 128.335 245.1 11.000
5500 190.5 142.056 246.6 11.069
6000 193.4 144.218 229.5 10.301
RPM GAIN%
2000 0.165
3000 1.448
4000 0.296
5000 1.057
5500 3.420
6000 3.867
Graphic summary...
NOTE : Last test (315) done with 235x45x17 tires at the rear - results WILL be slightly better with the usual 235x40x17 (currently 1 puncture)
ALSO : BMEP here only 'abstract' term - i can see flames coming...
Thanks to Quinton @ Dastek
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