LS3 isn't underrated, it makes 430 in the Vette, the Camaro has a harder inlet to get air in so it's 8hp less which seems reasonable. The days of underating are probably over. SAE certification is putting an end to that. If anything these motors are within +/-10hp of what they are rated.

 

Nice catch. Must be a typo with the rpm.

 

yes, but you forget, its 2008 NOW. not 1967. It's not even comparable, thats nearly half a century ago. with the SAE certification, the engine will make ~ +-5 hp of its rated HP.

 

May I remind you you can quote HP anywhere on the curve, if you so choose. Same goes for torque.

 

Exactly, I'm not sure where the confusion with some is, but it seems crystal clear to me.

 

Just give it a little more time as just before the cars are released GM will bump final HP by 5-10 HP in January.

They have done this on the Cobalt SS SC the Solstice, GXP, GP GTP, and many other cars over the last 4-5 years.

 

The rpm should have probably been 5900 for peak power... just like in the Corvette. It certainly won't make more power in Camaro.

 

I don't suggest it will make more, nor do I assume it will make less. It might and it wouldn't be a shock, but we can also agree that in the past the "Corvette" engine in the Camaro made the same numbers as the Corvette engine in the Corvette. Without regard to ratings...

5,900 RPM is the peak for the LS3 in the past...

Any HP difference would be more related to the cats and their ability to flow well. At least that's been my experience. Most manufacturers build the best efficiency into the airbox that they can... but paper filters are a must for nearly all makers, and intake noise trumps flow. Exhaust is similar, although engine note causes much more sweat in the tweaks as it's very easy to get an exhaust sound which is ***. Particularly if a sort of flat fire arrangement is chosen to improve idle vibration. One example is the exhaust sound at idle on Ls1 and Ls6.

All will be apparent when Camaros start to hit chassis dynos once in the hands of customers. RWHP and torque is the real deal in the final analysis.

 

I'm sorry, but it is simply not possible to make 422 HP at 5000 rpm if you make a peak torque of 408 lb/ft at 4500 rpm. Even if the torque curve were completely flat at 408 lb/ft, you would not make 422 HP until you were at almost 5500 rpm (rpm = hp * 5252 / tq) - and again, that assumes the "peak" tq of 408 lb/ft stayed the same to that rpm (by definition, "peak" means the value is less previous to and after that point).

Bob

 

I know what you are getting at, but I don't know why you say that is the peak "in the past." It is the current peak rating and is SAE certified. Obviously it may be different slightly in the Camaro, but 420hp at 5900rpm is much more likely than 420hp at 5000rpm for this car.