January 17, 2022
GMMG Owners and Enthusiasts Group
Jeffrey Griffin · 12h ·
Thought of this while driving home today. Seeing and knowing what engine CETA 7BB, PR1 BB, and all other GMMGs have brought this up.
How much of a difference does the hood decal hp differ from actual hp?
Talking dyno numbers. Not looking for exact, but a ballpark area.
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Wade Phillips
GMMG HP decals are flywheel HP numbers.
The actual dyno numbers on the cars are wheel HP. For example: PR-1 BB dyno sheet shows 558 wheel HP. Based on calculations
(I’ve been told to multiply wheel HP by 1.18 to make flywheel HP ) that means PR-1 BB flywheel HP is about 658.
Hence the 650 hp on hood. (basically you lose about 15% of flywheel HP through the drivetrain).
The numbers on the hoods of the cars is accurate. Actually, it’s usually a little lower than the real dyno numbers.
Thanks for asking & sharing. Jim
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GMMG Engine question
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daytonajim
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GMMG Engine question
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