It may be 3/8 also.

 

http://www.ebay.com/itm/Honda-S2000-...77cf1d&vxp=mtr

Look what i found. pretty cool.

 

bery nice

 

How is everyone running there vacuum/boost lines? I'm thinking about sourcing it from the open port on the intake mani from the PCV valve and using some t fittings to get the number of hoses I need

 

Ebay vacuum block

 

I have a vacuum block but I just don't have time to find a way to mount it anywhere. Looks like I'm gonna have to zip tie it haha

 

Mine is on drivers side front cross member brace. Just in front of alternator. Screwed right in.

 

That is where my cruise control and my catch can bracket is. I can't put anything else there haha

 

How necessary is it to use a vacuum block?

 

you don't really need one, but it is a more reliable source for vacuum than running a bunch of T's
though i dont really know how many ports you need.. one for a boost controller and one for a boost gauge? (assuming your compressor housing doesnt have a port)