Marina Blue

Ever since the April birthday bash, where a slide was presented showing the LS2 rated at 395 horsepower, there have been numerous threads in which people refer to the LS2 as having 395 SAE Certified horsepower. Since that time I had doubts that the 395 figure was correct, so yesterday at Carlisle I talked to both Tadge Juechter, Corvette Chief Engineer and Harlan Charles, Chevrolet Corvette Product Manager about that slide.

The first question I asked was whether the LS2 had ever been rated under the J2723 certification procedure. Both said the engine never received a certified rating. It is a costly procedure and certainly not worth doing for an engine that would never receive other than a 400 horsepower rating and due for replacement by the LS3.

I then asked about the 395 rating given to LS2 during the slide presentation. Both said the figure was incorrect, the slide was wrong, and that the LS2 really did make 400 horsepower. Both Harlan and Tadge told me the 395 figure came from the Trail Blazer SS and that someone in the chain of operations mistakenly used that figure. This was posted, on this forum, by Harlan Charles back in April.

No engines, that I am aware of, produced by GM, Ford or Chrysler and re-rated under the new methods lost 5 horsepower. I find it highly unlikely that the LS2 would lose 5 hp if it had been re-rated (which it wasn't). The numbers I saw, for US manufacturer engines, lost no more than 1 or 2 horsepower and in most cases gained horsepower.

So for all of you who are concerned that the LS2 was less than 400 horsepower, relax, it did make a true 400.

johnodrake

Tuners that I have talked to say they often see more than 400HP..

huckleberrydude

baseline on mine was a corrected 414 crank and 352 rwhp before blower

glass slipper

Wow! You actually went to the trouble of removing the engine and putting it on an engine dyno??? Did you have the stock exhaust manifolds and exhaust system (including cats) hooked up when on the engine dyno?

LS1LT1

For the record, I had suggested that very same probability when that chart was first posted here way back when, I knew it had to be the Trailblazer SS's info.



I never doubted it for a second.

Marina Blue

There was a time I was leaning 395, but as more evidence rolls in I think the LS2 would have rated 400 under any standard.

jdwk

Yeah I am little confused by the rating myself. The LS3 is rated at 36 more hp with the NPP, however, average dyno's are showing closer to 40 more at the wheels than stock LS2's.

So I was thinking the new rating system that the LS3 uses produces lower numbers than the old one, about 5-10, which makes up for the extra power on the dyno.

However, I remember when the Z06 was first coming out the original badges had 500hp on them, and then after it was rated on the new J2723 certification procedure, the badges changed to 505. It actually went up.

So confusion confusion. I had my first Corvette dyno experience last weekend, and was not impressed. Numbers were all over the place. Cars that ran equal mph traps at the track, had 30 hp differences on the dyno. Supercharged C5's were getting less hp than they had NA, and we were told an LS2 GTO threw down 280. The last part was just a mistake, but it didn't help its credibility.

I might let a tuner throw it up on the rollers again for tuning purposes only, but I have very little faith in dynos anymore. If you want to impress me, show me a timeslip.

dennis50nj

thats always best

32valves

welcome2try

BLU-BY-U

oh, barf. not again...

71stang99

I think that the LS1 and LS3 were sandbagging the ratings or the LS2 is underated or right on par. I dont see it being any other way as the ratings for the LS1 & LS3 appear above what they should be rated at and the LS2 is seems like its the under achiever of the two.

Rob 99

For me if it's 400 405 or whatever, im not hung up on any mystery or debate, it's the total experience i get with the car not just engine HP, it's a great platform to leave stock or modify, drive it and enjoy it