- Apr 18, 2006
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Take your (or that person's engine) dyno results (at engine or at wheel, the final number will be like that also), and divide the torque number by displacement. Try converting it to lbs-ft, so you can estimate how much torque in lbs-ft per cc that engine makes, and how much to expect by simply increasing displacement using the everything else unchanged, so if that dyno results are on a modded b16a, then you can calculate the est. horsepower gain by just plonking in a B20B bottom end with similar compression ratio with everything unchanged.sasuke said:
Remember that's it's just an estimate, and the actual may be different as you run into restrictions of your intake and exhaust systems, which might require changes to bigger exhaust piping, bigger manifold, etc. Even your cam duration affects the compression ratio, so you can usually assume 10-30hp difference out of that est. result if you get everything nearly right on parts and tune.
Mine is a little high, which is why when I calculate spoon 11,000 rpm monster, I get 255 instead of near 200hp.
Damn.. gotta get mine dyno'ed on a dynojet one day with correction for a more accurate result.
