after a day at the 1/4 mile i've started noticing a knocking noise coming from the back of the car,i only notice it when i start driving in 1st gear or reversing ,cant hear anything when going faster,this might just be down to road noise though,the best way to describe it is it's like the spare wheel is loose and knocking a bit,it is not loud.
there is nothing in the boot and i have checked the spare wheel ,jack and exhaust nothing seems to be loose.
classic sti6

 

Could be a number of things ranging from diff to wheel bearings - how many runs did you do as if there is a weak point on a car the strip will find it?

 

i did about 5 or 6 runs ,it was wet and i wasn't holding back,it was great fun .how can i check the wheel bearings,tried pushing and pulling the wheel there is no movement in it.it is really annoying me now,it doesnt seem to make a noise untill ive driven it for a very short time ,like i just went to the shop and i couldnt hear it ,but as soon as i got back in the car and started drivin it was back .took it to a car park and it is only really noticable when driving really slowly in 1st or reverse it isnt constant either drive in a straight line slowly no noise then a few knocks then nothing again and so on.
hope that makes sence.

 

antiroll bar drop links by the sound of it.time to visit your whiteline dealer methinks

 

thanks for the responce so far.
any info on how to check things like drop links ,bearings,diff etc would be greatly appreciated