HHR SS Gears
I have owned and driven both the Cobalt SS and HHR SS. They are two different breeds of cats. 300 lbs of weight makes a big difference. If you want your HHR SS to be faster than the cheapest fix is the stage 1 turbo upgrade. This gives the HHR SS manual over 300 HP and 300 LBS of torque. This more than compensates for the weight difference and there is no stage 1 kit yet for the 2008 or 09 Cobalt. Down side is problems that I am having with the stage 1 - IE: it keeps randomly dropping back to the "safe" mode IE: max boost 5 LBS. I have two stop engine for a couple of minutes and then restart - upon doing so it returns to the stage 1 programing.
I will be watching your progress. You'll have to keep posting some times slips as they get better and see where you're at. All i'm going by is a local guy with an SS cobalt runing in the 12.7-13.0 range with the trifecta tune, intake, and downpipe. His mph is also around 112-113. Nice to see someone else interested in track times with the SS. Thanks for posting and keep us updated!
you'd be the first i know of using nitrous...soon as you figure how to get it to work with our di let me know
Honestly, I don't plan on doing anything other than working with the tune for a while, next thing will probally be meth injection or MAYBE a 25-40shot of nitrous, and a downpipe. Thats all I really ever plan on doing, its just a family hauler. If I wanted a fast car, I would've kept my cobra and put a little more money into it to finish it off.
my hahn tune was purchased over a year ago. it cost $1000. i recently did a dyno run in the blazing azz heat with a hot azz car and hit 260whp and 310wftlbtq. if a stock ss is rated at 260hp and 260fltlbs with a 15% fwd drivetrain loss that means i roughly was pushing 220whp and 220ftlbtq...so that means i made 40whp and 90ftlbs for a grand with my hahn tune. anyone who thinks that is not worth it is an idiot. as previously stated i am going to go with trifecta's stealth tune in the next couple of weeks. and i will dyno probably the same week i get the tune if possible. if i come anywhere close to the 301whp claimed by the recent version of the tune than my 300 bucks are well worth it. there is no 1/4 mile track close to me... only 1/8th at atlanta motor speedway on fridays...anyway when i get a chance to track it i will and it will also reflect drag radials since there is no point in not hooking up
HHR ss 4.05 to Cobalts 3.84. If stated correctly the HHR should have the better gear for acceeleration.
The 4.05 Should accelerate the HHR faster than if you had a 3.84. The HHR gear would be ideal for 1/4 improvements. Am I missing something here or did you get the numbers reversed?
This is no different than a Camaro with a 3.73 going to a 4.11 to help with times in the quarter mile.
Plus 300 pound will contribute.
Where did you get the info on the engine size? never saw or heard that in any of the GM info listing any of othee LNF 2.0.
The 4.05 Should accelerate the HHR faster than if you had a 3.84. The HHR gear would be ideal for 1/4 improvements. Am I missing something here or did you get the numbers reversed?
This is no different than a Camaro with a 3.73 going to a 4.11 to help with times in the quarter mile.
Plus 300 pound will contribute.
Where did you get the info on the engine size? never saw or heard that in any of the GM info listing any of othee LNF 2.0.
sorry, not sure if you are aware that you are looking at 300 pounds. If so, you don't believe 300 pounds make a difference? You are looking at about .6 in 1/4 mile stock. You might be surprised.. Also, the final gear isn't the only gear in the tranny. I believe the gear ratio's (1-5) are different between the two. Three hundred pounds makes a big difference.
Rob
Rob
my hahn tune was purchased over a year ago. it cost $1000. i recently did a dyno run in the blazing azz heat with a hot azz car and hit 260whp and 310wftlbtq. if a stock ss is rated at 260hp and 260fltlbs with a 15% fwd drivetrain loss that means i roughly was pushing 220whp and 220ftlbtq...so that means i made 40whp and 90ftlbs for a grand with my hahn tune. anyone who thinks that is not worth it is an idiot. as previously stated i am going to go with trifecta's stealth tune in the next couple of weeks. and i will dyno probably the same week i get the tune if possible. if i come anywhere close to the 301whp claimed by the recent version of the tune than my 300 bucks are well worth it. there is no 1/4 mile track close to me... only 1/8th at atlanta motor speedway on fridays...anyway when i get a chance to track it i will and it will also reflect drag radials since there is no point in not hooking up
I will second or third the weight and gear responses. I had a 94 Z28 convertible that I went from a 3.42 to 4.10 gear and gained a little over half a second in the 1/4. Also us convertible guys always ran .3-.4 seconds slower than hardtop cars with exactly the same set-ups. It had to be due to the fact convertibles are 200-300 lbs heavier than hardtops. Just my 2 cents.
Now we're seeing some info come out!! Keep it coming. Dyno sheet comparisons are always a plus for different tunes. I also have the Hahn tune and am interested to see the difference in numbers. might have to switch! I only guessed about the gearing b/c I think the cobalt has an advantage towards the top end of the track b/c I think they can stay in the powerband in 3rd, and i'm just shifting into 4th right before the finish line. We probably do take off a little quicker, but in the time slip comparison with the cobalt had much better times from the 330ft mark on. Yes all the gears are a different ratio, I was just stating the final drive. All the info listed was found at chevrolet.com Point taken on the weight. For all this discussion we must have some 1/4 mile interest, so lets get some times. 1/8 mile or 1/4 mi. Lets us compare what we've ran.


