311
Well according to my log book I have flown 17 different 341's and 342 's the best one would get to 130 its straight and level and these were 342's
A 341 at IPS is 120 kts, at MPS it will struggle to get to 130 kts
At 81.3psi ( max cont) a 500D is around 135 to 140 kts
However all this depends upon blade track etc etc
Most 341's are happy at around 125 its as are 500's Much past that and you can feel the power through the airframe and they don't half drink the fuel.
If you have a 341 that will do 140 kts straight and level you have a very good one so best keeping it