I've searched far and wide for about 20 minutes and can't find wheel HP and TQ numbers for the auto SS. so my question is, has anybody gotten dyno'd(accurately) with the auto? and maybe with GMTU also?

 

If I know someone with a auto I could dyno it for you.

 

A general rule of thumb is to assume a 15% power loss to the wheels with an automatic transmission, so 260hp at the crank would be about 221hp at the wheels.

Of course the rule of thumb assumes a standard barometric pressure of 29.90 inches of mercury, at 60 degrees Fahrenheit, with a relative humidity of 35%.

 

15% for tq too?

if so then the auto would be:200whp and 188wtq?
and superchips says whp and wtq increase of 47.7 and 55.1 respectively for the auto...so 247/243(ish)?

 

The same for torque, but every vehicle is different, I've seen "identical" cars vary by 30hp and 40-50ft lbs of torque on the same chassis dyno in back to back pulls.

I've looked at some dyno sheets from Superchips and I take them with a grain of salt, they don't supply some info I'd like to see like ambient temperature, barometric pressure, etc. They don't even specify if the same vehicle is used for the baseline, and then the chipped dyno pulls.

 

thanks for the info!

 

Anytime! I might be an old "grey hair", but I still know my way around engines and making power.

 

Autos are supposed to be 230hp, with the 5 sp 260. I have also heard power is limited in the Auto only in gears 1&2. I have a 5sp, so I don't know

 

You call that salt and pepper grey ??

Try as I might I cant buy tires to hold the power this auto makes, and it is still de-tuned

 

Well I guess there's no sense in tuning it up then.