Originally Posted by 2005HHRauto

Great choice, as the HHR SS is a most excellent daily driver...
In these great times, a 'tune' is always the BEST 1st mod, & can be your only mod, as the HHR SS really responds GREAT with any 'tune'...
Even the cheapest & simplest 'tune' will put a smile on your face, & make your HHR SS proform like a true muscle car...

If you have E85 in your area, a simple E47 'tune', which is a 50/50 blend of 93 gasoline & E85, will turn your HHR SS into a mid to low 13 second machine at the track...
Just the Ethanol mix itself gives our engine 30 more horsepower, & 90' lbs of extra torque...
I have been running an E47 mix for the past 8 years, & it makes me smile everyday...

And a 'tune' can be really inexpensive if you know someone that has HPTuner, as he can purchase for $100, the code to unlock your PCM for him to 'tune' your HHR SS...
I have several 'tunes' posted on the hptuners.com site that you or your friend can learn from, just search for my posts, user name 2000Firehawk...

Our HHR SS really responses to just a few simple mods, as GM did such a GREAT job creating it...
1. Coring the 2nd cat gets rid of the exhaust restriction that we have, & can easily done for $5, & one hour of your time...
2. Replacing the plastic inlet pipe with the one that K&N sells for I think $25, that will get rid of our air intake restriction, & will take about 30 minutes to install...
3. A Hi-Performance motor mount from a vendor on this site, which costs maybe $100-$200, to make your HHR SS 'hook', to plant the power, & reduce the 'torque-steer', & will also take about 30 minutes to install...

That's it... Throw a set of slicks on it, & break into the 12s at the track...
Checkout my posts on this site, user 2005HHRauto for lots of info...

An expensive 3" catback will help a little at the track, but really isn't needed for a 100% street car...
Expensive engine part upgrades will probably help at the track, & I don't use any, & my engine is totally stock, as GM did such a GREAT job creating our engine..
The stock intercooler/piping are just fine, really no need to change anything...

I have done a 100 lb weight reduction with lightweight rotors/tires/wheels, & run 12.3s at the track, & it feels GREAT on the street...
I use my own 'track-only-tune' that lets me 'over-boost' the hell out my turbo at the track, & to be able to 'boost-launch' off of the line at 6lbs boost,
to be able to run 12.3s...

One-&-done, just a 'tune' & your HHR SS will put a smile on your face everyday...
3 more simple mods to 'correct' the 'little' things that will make your HHR SS AWESOME... & whatever/any 'tune' you put in doesn't need changed with these 3 simple mods...

I'm 65 & have been hot-rodding cars since I was 16, & the HHR SS is the simplest & easiest car to have 'fun' with, & I still LOVE it, & it still puts a smile on my face everyday...

Cars that I have hot-rodded in the past... 69 440 Charger R/T, 70 HEMICUDA, 71 HEMICUDA, 70 HEMI Challenger. 71 HEMI Charger, 71 340 Duster, 72 440 Charger, 74 360 CUDA,
74 440 GTX/Roadrunner, 88 5.0 Mustang, 98 Camaro Z/28...
I wish that I would've kept one of those HEMI cars...LOL

Keep-it-simple, don't mod just because you think that you need to do crazy things like in the past...