So when i'm driving my S2000 and i let go of the accelerator it makes a grinding noise underneath me, any ideas of what could it be?
Perhaps i need a new clutch?

 

Well your in a 00' like me, most likely clutch buzz. What RPM range does it occur?
Clutch buzz is harmless, and irritating to some.

 

Any RPM

 

A grinding noise? Can you find a similar video clip on YouTube? A clutch buzz and a grind are to separate things. Car acting different at all?

 

i really cant find a video but it sounds like a buzz i suppose. It doesnt act different at all, i just need to know if i need to change clutch to fix it.

 

Description sounds like clutch buzz. If thats what it is be happy! Clutch buzz is 100% harmless, and its not very expensive to correct.
Is this what your hearing?

http://www.youtube.com/watch?v=2GkWdHfFkjk

 

I agree it sounds like that could be the issue.

 

The AP1 clutch buzz only occur in very specific rpm range and condition, if you're saying its at all RPM, I don't think its the clutch buzz.

I would take it to a mechanic or at least take a video yourself and link it here once its up on Youtube.

 

All 2000 and most 20001 models that have the original clutch have a friction disk with springs that rattle in response to vibrations from the transmission during deceleration. Some are much worse than others and the only fix is a later model FD which is replaced in a clutch job. The clutch replacement in this car is relatively expensive usually running $700 to $1000. If you can stand the noise there is no other damage from the problem.