Just to chime in, I have the Speedtech uppers with QA1 coilovers on my '69 Bird. The springs are 350lb rate. The car sat real low and didn't seem harsh, but with an all iron pontiac motor I scraped my headers on a couple rolling bumps(ouch). I have recently purchased the speedtech lowers and 550lb springs. Not on car yet, but the speedtechs have delrin bushings and are so pretty I almost am afraid to install them.
Brian Hobaugh SCCA National Tour June 2014
First Hemi 'Cuda Convertible Ever Built
Short clips: Goodguys Pleasanton autocross and pit videos
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