Well I heard the weak link was the clutch so heres my story. I was at the track on the weekend. Car is an 09 SS with 5 spd and LSD only mod is the GM Stage upgrade. I have the Dejon spring and Hahn intercooler and pipes but don't have them installed yet.

My best time was horrible only a 14.7 @ 102mph with a bad reaction time of .72 and a bad 60 foot of 2.45 with the launch control off. I found that the car doesn't have the traction and would even bog at times half way trough first depending on how I left the line. But this isn't the best track.

On my 7th pass I shifted to 2nd and then it happend the clutch let go and the engine just reved up and bonced off the limiter. At first I thought I missed the shift. So I just took it easy put it in third and lined back up for an other pass. On the next pass same thing happend shifted to 2nd and it just reved. I pulled the shifter down just to make sure I was in gear and it was got off the gas then back on and it slipped again. Oh and both times I did full off throttle shifts I wasn't using the no lift shift.

On the way home I got on it in 2nd and it was ok, no slipping. I guess the clutch was over heated. Today I got on it a few times and it held. I let the car cool down between passes I only hot lapped it once or twice that day.

My car has 23000km on it and I know the dealer will just tell me it's abuse or I burned it out if I take it in or that they can't find a problem. It's ok for the street but I guess it can't handle the track. I'm going to keep it in there till it doesn't hold at all then I'll change it my self with something stronger. I've heard the weak link in these cars was the clutch but I didn't think I would run in to it till I was pushing somemore power then just the stage kit.

 

I know others have had the same problem and used the clutch upgrade from the Cobalt TC/SS, It was advised to get the flywheel too, as it would have to be resurfaced anyways.

 

I just had the trans replaced in mine and will prolly regret not upgrading the clutch. you prolly got yours hot, just like brakes , once they cool theyre ok. mine slipped once in second on the street, but I have not had any problems with the clutch since. do you think gm will warranty breakdowns at the track.

 

https://www.chevyhhr.net/forums/show...t=23231&page=9

I am wondering about the ''no lift shift'' feature for those who have the SS stg 1 with 5 sp. Is the tranny sturdy enough to withstand the no lift shift? Anyone here knows if the ABS reprogramming involved in this repair procedure, is done to adress wheel hop?

 

On my 7th pass I shifted to 2nd and then it happend the clutch let go and the engine just reved up and bonced off the limiter. At first I thought I missed the shift. So I just took it easy put it in third and lined back up for an other pass. On the next pass same thing happend shifted to 2nd and it just reved. I pulled the shifter down just to make sure I was in gear and it was got off the gas then back on and it slipped again. Oh and both times I did full off throttle shifts I wasn't using the no lift shift.

The stock clutch has an organic lining which overheated and thus the loss
of grip you had. Kinda suprising since clutch usually goes in 4th/5th gear
where the lower gear multiplier does not help torque capacity.
In my case, I had a tune that had such monster low end torque and it hit
so hard, that if I tried going wot in 4th/5th at 2500 -3000 rpm, the clutch
would slip. No problem in 2nd or 3rd and pull was as good as new vette.
I got GM stage 1 tune which is pretty stock like in 1st gear, way less
torque and response than aftermarket at low to mid range but then
as rpm rises it pulls harder and harder. GM did that to save parts and as rpm
rises they allow more boost. On my car, the clutch no longer slips in
4th/5th at 2500-3000 rpm because the GM tune lowers the torque in
this area compared to aftermarket. It raises it at 5000 up and my clutch
is OK there. If yours is like mine, you should see 19-20 psi rising to
21-22 at higher rpm

turbofreak

sae engineer

 

Yes turbofreak thats how mine is too. The GM tune keeps the boost low in the lower gears and ramps it up near the end of the rpm range. I actually think my car had more power in first when it was stock then it does now with the GM tune. I find that this lack of power in the lower rpms and gear makes it hard to get a good 60 foot time at the track(my car would bog due to the added traction at the track). I've got the mph but not the low end. I'm looking for a tune that will work on top of my GM tune to give me a bit more in the lower range. Does anyone know of any? I'm going to be getting HP Tunners soon so I might just try to do it myself.

 

I want Westers to take the best of his tune, great low/mid power and better
throttle response and combind it with the GM stage 1 tune. I will send him
logs from my HP Tuners Pro to guide him. We that have the HHR SS must
somewhat limit how hard the boost hits cause that is what I believe causes
the clutch slip in 4th and 5th.

tf

 

You should never hot lap an organic clutch. They need lots and lots of cool down time between runs. Once they glaze up, throw em in the trash.

 

Thats the sad part I wasn't hot lapping it. It had cooled all afternoon before it slipped.

 

Maybe your tranny has a crack, and is leaking oil in the clutch housing...

I hope this is not the case.