My RPD sure looks like it's peaking at 260-ish horsepower and 300+ lb/ft of torque when I floor it in 2nd gear and let her go to redline.


Do any of you gurus know if this is accurate? ...sure doesn't seem possible to be at the wheels, because my 5-speed car is stock (except for a K&N drop in filter w/original airbox).


I know the accelerometer can calculate these things (I bought a G-Tech Pro years ago that was very accurate). But the car can't know if I have passengers (extra weight), which would change the readings... etc etc


Thanks gentlemen!


(not sure if this is SS-Specific - please move to General Discussion if that's more appropriate)

 

It uses engine data, so it's numbers are at the crank. And I would think it's calibrated to give the max numbers spec'd by gm.

 

Thanks prod... I'll get out my old GTECH Pro and compare the numbers. I'll have to estimate the weight of the car since my scale only goes to 280lbs.

 

HHR SS weight = 2016 Camaro 2.0 turbo weight = 3,339 lbs...

 

Here is a discussion about it.

 

Thanks guys! I entered 3,500 lbs with me in it, full tank of gas...eh, it's pretty close.


While the RPD showed 260 horsepower, the GTECH Pro showed 209. The peak was in 2nd gear, I guess at about 50mph or so.


BUT - I also am running too much E85 in my tank now. In efforts to get cheap premium gas, I put in 5 gallons of E85 with 11 gallons of 87 octane. No, I don't have an E47 tune or ANY tune - heh. I was just trying to get my octane requirements for cheap. In any case, this might be affecting how much horsepower is cranking outta there.

 

Fwiw. I've seen my RPD show values of about 285hp and 310 lbs. torque.
Pretty close to the advertised claims of the 290hp, 315 tq for a HHR SS with the GMTU like mine.

 

5 gallons of E85 + 11 gallons of E10 = an E33 mixture, which I thought would be over the limits of the stock ECM ,'tune/program'. to handle.
If you're not getting any engine service lights, your ok, but you are definitely pushing the limits...
I've never tried anything over E25, on a stock ECM, 'tune/program', as the 'long-turn-fuel-trim', ( LTFT.),
will be close to being maxed out...
The LTFT can only 'swing', from -30 to +30, & if your maxed out at +30 with your E33 mix, on a stock 'tune', there's no room for corrections, if more fuel is needed, & you will run lean, & get 'service engine light/codes, & maybe blow-a-hole thru your piston ring-lands...
Therefore, if you're not getting any engine "codes", it's ok, & you will be making more horsepower with your E33 mix, but I won't push your engine, as you could go 'lean'...

At E20 , the 'mix' is strong enough to stop 'knocking', on any engine, & provide a nice power 'bump', your engine will run cooler, & smoother, go 500,000 miles , & still leave room for the ECM to provide corrections, during operational variables ...
And NO, Ethanol won't hurt your engine, as engines/fuel systems have been designed to handle Ethanol for the last 20 years...
I've been running a E47 mix for over 6 years now, with my best ET of 12.28 this past October...

So, anyone that has E85 available, should be running E22 in their 'buggy".
No tuning needed for E22
1 gallon of E85 + 5 gallons of E10 93 octane gasoline = E22
Always use 93 octane in the 'mix', for the octane 'bump' it provides, & the fact that we do have a turbocharger, that loves octane....
With all your other cars/trucks, without turbos/superchargers, you can use 87 octane gas in the E22 'mix'...

 

Thanks for the very thorough explanation of what my risks are as a result of my "frugality!"


I'm not pushing the car much since I have BandAids on my intercooler outlet pipe. But I'm going to be much more careful, in any case! (still no check engine lights, either)


FWIW, after I put all that E85 in the tank, my Butt-Dyno seemed to show significantly LESS torque... even though the RPD numbers didn't change, it sure seems like the performance declined! The Steering-Dyno concurs -- under 11lbs of boost, the steering wheel really needed to be enthusiastically controlled. After the 5 gallons of E85, the torque-steer is minimal.


Interesting, no?

 

Sounds like you're having fun with it now. Fix the pipe put a tune in it and hang on to the steering wheel, or, make sure you have it pointed in a direction.