To answer your question and not go on about speed limits on public roads, there arent any speed limiter's on a FR TDi other than the limited power/weight/aero that stops the car.
I assume you have done this 139ish on a stretch of tarmac, since gone back after the remap and no change of results?
I had the same thing happen to me at 142mph (on the clock) I personally dont think a remap/exhaust/induction kit etc has increased the top speed of my car to any degree worth shouting about. It does get there alot quicker mine
Saying that, ive seen 149mph (on the clock) since both of those tests.
Depending on how many miles the car has done, and what mods you do, you might see a change.
One question that you might want to think about, does it matter if it has got a limiter at 140mph!? Its alot faster than you should be going on any public round, and I cant see you needing even that sorta speed on a race track with a mere 180bhp wont get you there quick enough before you run out of track!
Id be more worried if your 0-60 time, 1/4 time 0-100 etc etc time havnt changed since the remap. Which im guessing they will have, and generally they are the more important figures to be worrying about.. after all the Atom/Elise/VX werent built for top speed, but can still upset most supercars round a normal race track