The 509 Touring Cam is designed as a bolt-in, high torque cam. 180 psi cranking compression, no need for compression releases. For 88 CID engines with stock compression ratio. Idle-4500 rpm.
Can be used with stock valve springs.
It's no surprise that the S&S 551 cams for Harley-Davidson bikes have become a favorite with late model riders. The only problem is that, due to the .550" lift, the 551 cams can't be installed in Twin Cam 88 engines without also installing a set of high lift valve springs. That means that the heads would have to come off just to install a cam. That's a lot of work and added expense!
Based on the success of the 551 cams, S&S has come up with 509 bolt-in torque cams that work with stock valve springs in Twin Cam 88 engines. Like the S&S 551 cams, the 509 cams are great for low and midrange torque, but the 509 cam's lower lift allows them to be bolted into stock engines with stock valve springs. That saves a lot of time and money on the installation, which makes the S&S 509 a lot more attractive to owners of older Twin Cam 88 powered bikes.