Call your fuel pump manufacturer.

I run the 300 Magna-fuel and it requires a 100 micron before and whatever you want after like maybe a 40 to trap more and yes it does matter on the pre side especially w/big pumps............

thanks for the people that answered my question. yes I put new needle and seats in, that's why I wanted to try a finer filter. when I went to monte's nitrous class he said that pump will handle what ever you put in front of it. that's why I have it on my one car and got another cheap so I'm using it on my other car.
There is a definite difference in filter flow with the same micron. I ordered one thanks