Hi
Contacted this company about making rear springs to lower my HHR SS:
EATON Detroit Spring - The leading manufacturer of leaf and coil springs for the street rod and restoration industries
The reason I did was because of two things
1) The Cobalt SS springs (p/n 25821162) from GM Parts Direct the last time I checked was on national back order. No telling when you might get them.
2) Bought OEM used rear Cobalt SS/TC springs off a member on the Cobalt SS site, which had a different p/n than the ones from GMPD, they had same static height and number of coils but had a wire diameter of .500" vs the HHR SS spring which is .650". They lowered the back a little but the car is not level.
This company said they could make just rear springs for our HHR's but it would take 25 orders for them to do it at (you ready for this) $200 plus shipping.
If the 162 spring is that hard to get and this company is willing to make the springs maybe people on this site that would like to lower just the rear's can contact them also and see if the price of the spring can come down to something more in the ball park of the ones from GMPD.
Thanks

 

Torches come to mind, in one way or another.

 

I think a little more detail needs to be included. Spring rate wise, will they be made on par to the SS's stiffer springs ?
Will they be a standard coil spring ? Or one of those progressive types that have the "dead coils" that load and unload( or touch together ) ?
Also. How much drop are you looking for them to make into these ?

 

Hannibal get da torches, measure where your frame will be at fully lowered and gently warm up the coils, I used to go to 4 inches for the lowest point cut down a price of lumber to 4 inches and heat those coils until the frame point touched the block of wood

 

I really didn't get that technical with them other than saying the springs were a pigtail design to see what response I would get from them.
I had emailed them about my question.
Calling them is a better option to ask your questions.
Still looks like the rear could go down another 1".

 

Was this done on your HHR?
What part of the coil to gently warm? Just the middle?
From my understanding heating coils to drop ride height is taboo.

 

No not on my HHR, I speak of days gone by when the internet was for the military and E bay was the 5 th stall down the building where I used to work at the Chrysler dealer!
I used to gently warm up the middle spring coils, don't know about taboo but it worked!
Then I purchased a coil spring compressor and just cut 1/2 a coil at a time to get the correct ride height! then go to the opposite side and cut just once the total amount form the first spring. This however will not work for the pigtail springs on our HHR's

 

Don't be one of those idiots that doesn't re-aim your headlights