Help on Suspension Ride quality
 

Hi, I currently have a euro-specs MY2006 2.5l WRX. Besides a Cusco front and rear anti-roll bars, the suspension is stock.

I regularly use the car to travel along a highway which looks flat to the naked eye BUT is actually gently rolling up and down. The problem is that the WRX reacts to the gently undulating highway by quite violently oscilliating up and down. It's like the suspension has no control of the up and down movement (no damping). It's so violent that passengers get car sick. The car has been like that since new and I've sent it back to have the suspension tested (it passed).

On smoother surfaces it rides ok and is firm"ish".

I would like to make some changes to the suspension but also have not because I have no idea if the problem is due to strong springs/weaker shocks or vice versa. Also, most of the aftermarket suspension lowers the ground clearance - something which I cannot afford since there are huge potholes, huge sleeping policeman and steep car park slopes here. (have scrapped the front even on standard suspension height).

Anyone with the same experience and any recommendations on what to change to ? I am looking to improve the ride quality (no more hopping) but not at the expense of handling.

Thanks for any suggestions... SH