L78 vs COPO in 69 ('real' engine horsepower ratings)

**JRSully** · #1 08-01-2023, 10:56 AM

One of the old tricks the manufacturers used was to take the HP reading (to be reported to the world) at a LOWER rpm and use that, eventthough the power band was still advancing up. One of the tools to keep the insurance companies happy...

**69 Post Sedan** · #2 08-01-2023, 12:23 PM

Quote:

Originally Posted by JRSully

One of the old tricks the manufacturers used was to take the HP reading (to be reported to the world) at a LOWER rpm and use that, eventthough the power band was still advancing up. One of the tools to keep the insurance companies happy...

Correct…..the L88 was rated at only 430hp at 5500rpms. But we all know that wasn’t even close to the rpms the L88 could twist. It’s my understanding that they didn’t want to outdo the hyped up 435hp tri-power motor.

Kurt

**Steve Shauger** · #3 08-01-2023, 01:16 PM

Quote:

Originally Posted by 69 Post Sedan

Correct…..the L88 was rated at only 430hp at 5500rpms. But we all know that wasn’t even close to the rpms the L88 could twist. It’s my understanding that they didn’t want to outdo the hyped up 435hp tri-power motor.

Kurt

Also keep the lethal L88 out of the hands of novices. It was as close to an all out race motor GM had built at the time.

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