They look like 174's.
I have the same blowers.

Thanks for the reply. Maybe I should just keep hem for now. I seem to always get that Tim Allen bug wanting to make it bigger badder faster...I need a shrink...

I think they are great blowers. If your looking for over 600hp you may want larger.
I plan on intercooling mine this winter and running a bit more boost.
Going to put on dyno and see what we get!

They are 174's.

How much boost are you running????? You may be able to try a smaller top pulley or innercool them.

here is a pic of my motors, they have kuhl bros. single 1050 dominators on 514's making 8lbs of boost. another combo with a single 1050 on 540's made over 750 hp.

I am running 5lbs of boost around 4800RPM. Running just shy of 600HP each. I was thinking of the options to cool the intake charge and would rather slow down the blower before I intercool. I would love to do both but budget just wont allow that yet.