errrrrrrrr........i think you'll find there is!

Standard T3's have the dynamic ring seal.

Phil79 as tabetha is saying though, on a standard T3 they have just a standard dynamic ring seal, which basically like a piston ring, has a tiny tiny gap in the seal, and it relies on simple physics to contain the oil within the turbo, so in this case the back pressure in the exhaust exceeding the oil pressure within the turbo core.

If you start fitting large diameter exhaust systems you majorly reduce back pressure and its common for the oil enter the exhaust, so a step gap seal is what you'll want in your turbo to control this, which basically means there is no straight gap in the sealing ring