Ls2_HHRss

Does anyone have the exact numbers of the Auto SS? I can't find the exact numbers for the Auto since it wasn't 260/260 like the manual.

I do know the Auto was 235 HP but not sure about the torque.

Thanks in advance!

2005HHRauto

223
google is your friend...
I just googled; 'hhr ss automatic engine specs' & got 465,00 results...
2008 Chevrolet HHR SS - First Drive - Motor Trend

I doubled my torque...

Remember both the auto/manual 2.0 engines are exactly the same, so the automatic engine still makes the same power...

Our PCM is basically a 'torque-control' type of PCM...


The PCM just limits the torque with the automatic...
This can be easily changed in about 5 seconds in the PCM, by using HPTuner software.
There is a 'table' in the PCM for 'percent of available torque' by gear/RPM.
With the manual, this table is set to 100% everywhere in all columns/rows.
By changing this table in an automatic HHR SS PCM to 100% everywhere, the full power, of the stock PCM, returns to the automatic....

Ls2_HHRss

Oh trust me, I did. Car and driver says the AT is 250 HP and 237 trq. So who really knows right? Lol

2005HHRauto

Actually we do know, it's 260/260, the same as the manual, but limited in all gears, except 3rd gear.
In 3rd gear, as seen in this Gear/RPM table of this stock HHR SS automatic chart, we have the full 260/260 with our automatics 3rd gear...

I believe that they took an 'average' of all 4 gears to arrive at the 235/223 figures...
Also, at some RPM level we may really have that 250/237 average figure...LOL



Now, to confuse you even more, our engine can in fact make whatever hp/torque that you want, within reason...

With all the stock PCM tables as is: 260/260

With some of the tables changed, as in the GM performance 'stage' kit: 290/315
No engine mods are needed with the GM performance kit, but premium gas is mandatory. The GM kit contains a pair of 'sensors' to better monitor the turbo boost, but still a stock engine.

With better changes to the PCM by a 'tuner': 350/350 can be easily reached with no engine mods, premium gas mandatory, & still a stock engine...

In my case, with my PCM changes: 350/450 , still no engine changes made, but instead of premium gas, I use a 50/50 mix of gas/E85, a free flowing exhaust & a K&N plastic intake tube with a K&N filter, to make a free flowing air intake track, still a stock engine...

If you 'open' the engine up to change pistons, cams, bigger turbo, etc. with max PCM changes made: 600/600, with race gas or E100

In fact, if you wanted to, you could change the PCM to create: 100/100 , run regular gas, & probaby get 40 miles per gallon, LOL...

RJ_RS_SS_350

Why does the chart show 7 gears, with one labeled "0", and no "6"?

2005HHRauto

It's just an HPTuner thing...
0 maybe neutral or park or reverse
7 maybe neutral or park or reverse

I can't remember what was what...

Ls2_HHRss

Thank you for the great information. A little confusing but I think i got the jist of it. Lol

RJ_RS_SS_350

I dunno if there's just too much information missing or what...

Outside of 3rd gear, it maxes out at 79%, which is only 205.4 lb-ft.

I see this is a "general" tab, there is also an "engine" and a "turbocharger" tab.

2005HHRauto

All of the 'engine' tables in both the manual & automatic PCMs are the same, & there are 100's of 'tables' in the PCM...

Max engine Torque 'allowed' is always changing in the automatic, because of the percent limits that GM put in place in this table of RPM vs Gear.

So they took an 'average' of all Gear vs RPM figures to come up with the 235/223 for the automatic HHR SS, with the 'marketing' departments approval...

Remember, it's the exact same engine in both manual & automatic HHR SS.

With the 3rd Gear vs RPM column, GM is letting the full 260/260 of the stock engine PCM, to go thru the automatic HHR SS

And you are correct, the automatic is severely limited in 1st, 2nd, & 4th gears.
If GM told the truth about how severely limited it is, with a rating of say, 205/205, sales wouldn't be as great.
Marketing had a say in the numbers...

I still remember my test drive in my new 2009 HHR SS.
When I 'punched' the gas petal down, when cruising along at about 35mph, I bust out laughing, at how bad the power limiting really was...
My wife asked me what I was laughing about, & I didn't have the heart to explain to her what GM had done to our automatic 'buggy'...

I knew all about the GM Performance kit, before my test drive, that would 'unlock' more of the power to 290/315, & ordered one ASAP...
I also knew that HPTuners was 'unlocking' more of the the stock PCM tables, to let as take full advantage of the 2.0 turbos power potential.

Now GM really had issues with putting power behind production cars using our 4T45E automatic.
2007 Malibu as an example:
With the 3.5 V6 which had appox: 220/220 they used our 4T45E automatic.
When they put in a 3.9 V6 with approx: 240/240, they used the 4T65E automatic.
So our HHR SS rating of 235/223 was probaby the highest rating used with a production 4T45E automatic.
So, why would they release & warranty, the GM Performance kit with a 290/315 rating for our 4T45E automatic.
I believe that our new 'torque' based PCM allowed such precision, in the control of real-time power, that testing must've shown that our automatic could easily handle 290/315
So you guys that want 260/260, but are afraid of 'tunes', have a tuner just change the RPM/Gear table values to 100%
With just this change, your stock automatic will feel so much better, & your automatic will be fine.
Hay, I'm at 350/450 with slicks & 1.7s 60' times with no problems with my automatic.

On a side-note:
Some of you have heard of the so called 'learn-down' feature of the stock PCM...
When you add power adding parts to your 'buggy', it feels great at 1st, then the PCM quickly 'learns-down' to the preset stock PCM values...
What really is going on, is that our PCM is totally 'torque' based..
The stock PCM is programmed to allow a certain 'torque' value at every point in time of every RPM/gear/temperture/air pressure/water temperture/ect/ect setting in the real-time running of our engine...
When your power adding part allows the engine to make more 'torque', the stock PCM will quickly 'learn' & restrict the 'torque' increase to whatever the max is allowed in the stock programming...
Most tuning in our PCM is just increasing the 'torque' values allowed..
I default most 'torque' values in my PCM to whatever the max setting is, so that I'm not limiting my power allowed.
I'm thinking that most max setting are at 1,000 foot lbs of torque...
I will never reach this figure, & I know that I will always get max power available.
By the way, the stock rods will bend at 600 foot lbs of torque...

aradmahogany

Even the 2.4 LE5 can be made to be a pretty potent power plant, which is also why these cars are so damn reliable. If you are daily driving an engine and transmission combo with, in my case, roughly 179 HP but could easily handle power in the high two or even 300 hundred range, then the daily use of the LE5 and 4T45E is basically a leisurely stroll. Same with the LNF.