This camshaft is perfect for a near stock 1JZ-GTE Non VVTi engine! It provides improved low to mid-range power, fast spool, and excellent throttle response, making it ideal for street cars. It is compatible with both stock twin turbo and single 54mm-58mm turbo upgrades. You can use OEM valve spring for the stock boost and rpm limit. However, if you want to go up to 7500rpm and 30psi boost, Kelford Cams recommends using valve spring KVS109-1JZ.