What is the answer? Nobody knows...

This is a real colondrum, taht might not make sense, but if you figure it out, tell me immediantly. Then I will try it (first person wins) and tell you if your right next week. And go:

170:251 - 121 + 441 - 340 + 130 - 113 + 409 - 253 + 130 - 181 + 297 - 149 + 081 - 088 + 467 - 059 + 306 - 229 + 345 - 351 + 117 - 047 + 353 - 216 + 401 - 147

This answer mght not make sense, but tell me anyways!!!
You only have until next Thursday!!!