Quote:
Originally Posted by SOCAL.M6.ZLE
Thanks for the clarification Rob! That said, here are the revised calculation...
peak RWHP was around 6,100rpm... Dynamic Airflow was 5,600 lb/hr or 93.3 lb/min = * 10 as a representation of crankshaft hp would equal 933hp at the fly . At 838rwhp x 1.18 = 988bhp so it looks like a 6% difference so far?
Now... checking at 6,950rpm... Dynamic Airflow was 6,114 lb/hr or 101.9 lb/min = * 10 as a representation of crankshaft hp would equal 1,019bhp...
Am I doing this right?  |
There you have it. I'd say you are in the ballpark.
I think most people find that the M6's lose about 12-13%, so
933*0.87 or 0.88 = 812 to 821rwhp
There is also an odd bump in the dyno around 6100 where you had your peak. If that was flattened out, it looks like peak would still be about 835-840 but around 6300rpm. I'd wager that your lb/min at 6300rpm, times 10, times 0.875 would be about 840.
The higher airflow numbers you see near 7000rpm where the power doesn't match, is where the engine is dropping off. It might (or might not!) be able to take some more timing as the engine gets less efficient in that last 800-900rpm approaching 7000rpm. If it could take more timing, then your HP peak would push higher toward the 880+rwhp range (1019*0.87 or 0.88).
In any case, I think the Dyn Air estimation works pretty well here. It's just an estimation, and assumes you are using that air the the best of it's ability.
With the old design Terminator cam, I think that might be what's holding back the last 1000rpm or so. I believe that cam is smaller than his current design. I think Ted added duration and widened the lsa on the newer ones, which would make that thing pull to 7000+. You can see it in the
boost curve here. Above 6000, it ramps up the boost because it can't get it out of the cylinder.
This is just my opinion. I'm no expert here!
