Has anyone experienced a knock sound over bumps with lowering springs? It does it only on the drivers side in my 08 997TT.

 

Yes. Most likely it's the spring hitting off the perch. I had that issue with my Cargraphic springs. Very common.

 

Thanks, So this is common with lowering springs? I did not notice any noise until I put about 2000 miles on the car then it started knocking. The installer said that it could be the perch as well and also stated that it could also be the spring compressing and knocking when the coils rub together. He says the reason the noise did not occur initially is because there was a plastic type coating on the spring that wears off then the noise starts. I figured I would get other opinions on the matter.....I am very annoyed by the sound and may consider coilovers if they DO NOT make the knock sound.

 

you can either wait for your stock shocks to wear out due to the aftermarket springs you have or go to coilovers now.

 

Ive had my GMG springs for 9,000 or so miles now and have not experienced this. I would pull those f-ers out though if it did! That would drive me nuts and to coil overs in a hurry.