Quote:
Originally Posted by MauriSSio
say what you want, but 600+ of those horses are consistently finding their way to the rear wheels which is about 100rwhp more than the 580hp zl1
since youre so versed in sae ratings, what do they (sae certifiers) say about the overrev feature on the GT500? and how does that affect the ratings?? links?
is it at all possible the 662hp rating is at the designated "redline" and the "overrev" rpm range isnt part of the sae certification since its technically limited?? sources please.
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Quote:
Originally Posted by Barracuda
The "overrev" doesn't come into play in the certification at all. The engine is certified on an engine dyno. It makes what it makes. As long as the engine can operate at that engine speed in-vehicle, the manufacture can advertise it. In the case of the GT500, it makes peak power at 6500 RPM. The fact that it can run at, and be shifted beyond, that point makes the advertising legitimate.
NOTE: When I say it doesn't come into play at all, what I mean is it doesn't limit what can be advertised. It obviously comes into play in allowing the vehicle to operate at and above the engines peak power point.
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Well, if Automobile magazine has it right, the 662hp rating is WITH the over rev feature. From the article:
"Seven grand from a huge stroker of an V-8 means piston speeds approaching those of a NASCAR engine, so all of the rotating masses are forged for lightness. And strength: at maximum load, the supercharger takes some 150 hp to run, so the engine block is actually supporting more than 800 horsepower. The high revs and enormous power output come with a corresponding buildup of heat, and for that reason the GT500's engine can be revved past 6250 rpm for only eight seconds at a time. Each second spent over 6250 rpm must be redeemed with a second under 6000. If the full eight seconds are used up, the engine computer will lock out the overrev function until the engine has been under six grand for fifteen seconds and has ventured once under 5000 rpm.
Since the 662-hp rating occurs within this overrev band, you can technically have all 662 hp only for eight seconds at time. That would be a problem except that the only gear in which you'd be able to exceed 6250 rpm for more than eight seconds would be fourth while going uphill -- as you approach the shift point into fifth at 173 mph. The GT500's top speed is reached in fifth just below the 6250-rpm limit. In other words, the eight-second limit is irrelevant."
Read more:
http://www.automobilemag.com/reviews...#ixzz1vvT8aDlM