Pulsating speed along curve

[thorsnuts]

Hello..

I'm trying to create an effect like blood pumping through a vein.
What I've tried is modulating velocity over time but it seem to effect cluster of particles instead of the entire group... so it doesn't give me that pulsating effect Im going for. I also tried warping the cached file but after the slow down it speeds up to fast to compensate for the lost time.

My next step is to make a longer cache file, stretch it a bit and play with keys.

However.. creating the effect in ICE would be much more efficient.

thanks for the time.