MidnightBlack

For a 2010 SS LS3. what rpm should you shift at for best et's ?
Thanks

JakeRobb

As high as you can without hitting the rev limiter.

2010_5thgen

id go about 500rpm before redline. thats about the peak hp/tq.

JakeRobb

Shifting at the peak is a waste! There are two areas of the powerband that offer near-peak power -- right before the peak, and right after it. You should shift to maximize area under the curve, and in the case of the LS3 (and nearly all other engines, actually), that means you should be getting as close to the limiter as you can.

HAZ-Matt

This is exactly right.

2010_5thgen

thats why i said before redline. because often, the peak power is not at redline. it is normally within 500- 1000 rpm from redline. i believe mine is 500 before redline.

JakeRobb

Your post indicated that they should shift ~500rpm before redline, which is the power peak on your car (and the OP's too). I'm saying that's wrong; you're wasting all of the power available between peak and redline, and instead landing 500-700rpm lower on the powerband. Run it right up to the limiter.

I'm hoping this image, which I just whipped up in MSPaint, will help to explain. It's very rough, but I think it works:

Bob Cosby

Those images explain it very well, IMHO. For maximum acceleration with stock LS3, shifting as close to the rev limiter as possible - without hitting it - is as good as you'll get. Peak HP is not what is important, rather, it is average HP through the rpm range in each gear.

Slappy3243

Yes, shift right before you bounce off of the rev limiter. However, shifting about 400-500 RPM before redline is what I do on my LSx cars since the tachometer lags very slightly and I find shifting like this gets me to the next gear right before I hit the rev limiter and lose power. If I wait until I hit the redline on the actual tach in real-time, I hit the rev limiter. I hope this makes sense.

Bob Cosby

Makes perfect sense. Not only might tachs be slightly different, but different shifting styles/speeds will result in a different rpm in which one will begin to execute the shift. The key is to get as close to the limiter as possible - without hitting it.

graham

If you have a dyno sheet from your actual car and if you know the RPM range in length you will be using in any given gear, then you can plot that RPM range to.. usually... 8% past peak HP.

You can actually ignore torque at that point in the game since HP is just torque-in-time and time is the name of the game.

2010_5thgen

ill check out my sheet at home. but liek i said when im getting into it, i shift about 500 from redline. which is 5500 rpm. and i believe that is right where my peak hp is.

JakeRobb

You're welcome to do that all you want, but if you race someone with an identical car, and they run it all the way up, you're going to lose.

2010_5thgen

they run what all the way up? you just said not to run all the way up to redline....

edit: honestly, i dont even really care enough to have this conversation. no offense. its just not worth it.

96_Camaro_B4C

He is saying that if you were to race against someone who shifted just before hitting the redline / rev limiter, while you shift 500 rpm before that point, you would lose.

Also, isn't redline in an LS3 SS around 6500-6600 rpm?