The Billet GSC Power-Division S1 cams for the Mitsu Evolution 4-8 are designed for those with the stock turbo up to the 550WHP Stock location or aftermarket turbo kits. These cams will not sacrifice any bottom end loss over stock cams; nothing but gains and will promote faster spooling of the upgraded turbos. Gains of 30-55whp (depending on Turbo) have been seen by simply bolting the S1 cams in. Designed for a rev range of 3000-7500rpms, these cams work well on the stock valve springs with lower boost and RPM goals. Idle is slightly rougher than stock. Made 100% In The USA!
**If using aftermarket cam gears(especially AEM) check the bolt lenght, some cam gears are too thick for the OEM bolt on the Billet cams, a 40mm underhead length bolt may be necessary in this case**