Looking at some of the LS3 dyno postings,compared to the LS2 numbers. Could it be that the LS3 is producing well above the 430 bhp or maybe the LS2 is NOT producing 400 bhp. I mean giving a 10 to 15% drivetrain loss,something seems amiss.Unless I just misread some postings (I know you can`t believe a lot of what you read). Any one else noticeing this. Would like to see some stock dyno postings for the LS2 and LS3 respectfully. Seems to be more than a 30(36) hp advantage.

 

I think the LS3 is underrated. Probably so they don't take business away from the Z06

 

If the HP is not underated, it sure seems like the torque may be...the LS3 sure pulls better....especially when you downshift at speed....60 to 100 sure comes up fast.......

 

Thats what I keep hearing. perhaps for insurance reasons. Didn`t one of the big three do that back in the late 60s early 70s?

 

 

I've driven all three, LS2, LS3, and LS7.

The LS3 does pull better than the LS2. It feels about 30 hp better to me, maybe 40, so I believe the ratings are accurate. You can tell the diff, but a good driver in an LS2 will have no problem keeping up with an average driver in an LS3.

Please don't confuse either with the LS7. That puppy GOES!

 

All 3 Big 3 did that in the 60's and early 70's....everything from the Boss 302, Z28, Hemi 'Cuda and 427/435 'Vette were way underated for the insurance companies.........but it was a GREAT time to grow up though!!

 

I have an 05 z51 MN6 and I drove a friends new 08 non-z51 MN6 last week. His car is FASTER! But mine pulls harder from the start through 1st and 2nd gear. Then his just walks after that. You can feel the difference in HP. I think mine just fells stronger from the start because of the z51 gearing, but it may not be. All I can say, is yes the LS3 is stronger.... I have also driven an 07 Z06, and it makes both the LS2 and LS3 feel weak.....

 

Would like to see some dyno postings of both the LS2 and LS3. we all know how awesome the LS7 is. Not just seat of the pants driving. Thanku in advance

 

enough already!

 

The LS3 is SAE certified, as is the LS7. The LS2 was not. The very purpose of the SAE review and certification of the motor was so that ratings cannot be hedged or inflated by the manufacturer. They are limited to a 1% +/- variation in the actual recorded output.

Comparing Dyno graphs of an LS2 equipped car to an LS3 equipped car is not really apples to apples either due to the drivetrain changes for 2008 (both manual and auto). It seems to be presenting that there is less driveline loss in the new transmission than what the LS2 equipped cars have and some of the "standard" assumptions regarding driveline loss are out the window.

 

Talon......thank you for not letting AO 08 put a damper on our fun here. I wish people would not do that to a valid thread like this......ask him which wax he uses....I DO think perhaps we've seen enough of those.
Repeat posts are a fact of life here, and we should all be considerate to each other when that is done.........

 

Over-rated...but how? Dyno printouts are fine but real performance results may be something else. I expect the LS3 to be slightly faster than the LS2 but in looking-at the 1/4 mile times in the showroom stock category, I'm surprised that the LS3 has not yet conclusively demonstrated its "superiority" over the LS2. The last time I looked, finally one LS3 has broken-into the top ten...at #10 on the list. Granted the LS2 has a 3 year head-start and the LS3 will likely prove it is faster but IMO it is extremely close.

I checked the Corvette Action Center for the GM press releases on both the LS2 and the LS3. The performance numbers provided by in the GM press release for the 2005 LS2 were as follows:

"The 2005 Corvette reaches zero to 100 km/h (62 mph) in 4.2 seconds. With the optional Z51 Performance Package, 0-100 km/h acceleration time improves to 4.1 seconds. The 2005 Corvette covers the quarter-mile in 12.6 seconds at a speed of 183 km/h (114 mph)."

Unless I missed something, the GM press release for the LS3 equipped 2008 C6 only listed a 0 to 60 mph time for the paddle-shift equipped C6, as follows:

"The LS3 with the six-speed paddle-shift automatic is the fastest automatic-equipped Corvette ever, with 0-60 mph capability of 4.3 seconds."

I note the rating for the 2005 LS2 C6 is 0 to 62 mph while the 2008 rating is 0 to 60 mph. I would also expect the 2008 C6 with a manual shift will produce a slightly faster time than a paddle-shift. I also expect GM's performance numbers to be the ideal, best case scenario.

Again, I believe the LS3 should be slightly faster than the LS2 but based on the current listings of 1/4 mile times in the showroom stock category and based on the official GM press releases, I can only conclude the actual performance between the LS2 and the LS3 is extremely close...perhaps even comparable. The LS3 may win on a dyno but to date, there is not an over-whelming body of real world evidence to support the claim the LS3 is significantly faster.

Something may indeed be over-rated but at this point, I'm unsure exactly what. I'm not knocking the LS3...by all accounts it is a superior engine to the LS2...more power is better! I just find the real world results and data contained in the GM press releases an interesting paradox. I imagine as more 2008 C6 owners hit the drag strip we will see the LS3 creep-up in the ratings with an LS3 eventually surpassing the LS2 in 1/4 performance. Time will tell.

 

You may have answered my ?.....SAE rating. So I`ll pose another one. If the LS2 was to be SAE certified. What would it`s BHP numbers be?
Seems the SAE rating lowers an engine s BHP

 

The SAE rating is simply a witness and certification of the actual test that was performed. While it applies certain standards for the test methodology it - in and of itself - will not raise or lower a horsepower number. What it does do is prevent the manufacturer from publishing underrated or overrated numbers from a test. So lets say hypothetically that the LS2 was tested and witnessed to be 395 hp. It would not be a stretch for the manufacturer to publish a 400 hp number just by rounding. Under the SAE certification they would only be able to publish a 398.5 hp (395*1%=3.95).

Inversely if they wanted to produce a sleeper, in the old days a motor that may have actually dynoed at 425, they may have publised a 400 hp number to keep the insurance companies from balking at the performance.

 

 

FWIW, my 07 MZ6 dyno'd at 353/357 stock with 450 miles on it.

 

Agreed....

I thought the whole brouhaha about SAE ratings was settled a while back, and the upshot was that, yes, the LS2 really does have 400hp, even when SAE rated.

 

It is alot like a ferris wheel. One minute you are on the top, the next, you are on the bottom. Nothing is ever really "settled" some things just take longer to come back around then others.

 

Was fortunate enough to own a 67 427/435.