Anyone done this? I'd planned on using the stock one until I out boosted it. I've got an extra one though and was thinking about crushing it. Is it just a matter of putting it in the vise and crushing it down the 3mm until the cap is even with the nipple?

I'd do this instead of crushing it:

http://www.thedodgegarage.com/turbo_bov_mod.html

I agree with Eric totally. I've run both modifications of the BOV and the drilled version acts very much like stock with the extra gift of BOV sound. The crushed BOV holds the pressure required but when it opens it opens violently and feels as though it's causing undue stress on the engine components.

I agree with Eric and Marcus. That seems to be the best way to do it. However, I think I'm having better luck with my crushed BOV than Marcus did. It acts like stock, but doesn't leak at high pressures. Of course, I don't think my BOV is crushed as much as Marcus's was either.

OK, I've read the page twice, let it sink in for a day, then reread it again. I can follow the directions but I'm having a little more trouble following the theory. With a crushed BOV, altering the spring rate by crushing is straightforward even to my simple mind. Although I don't doubt the dodgegarage method as being a better route, I'd like to understand what I'm doing here to.

Basicly I started to get a little lost with the whole 'quick release' and swapping the line back to run normally bit. Is the BOV usable for sub 30# boost rates when modded this way?

I've got a feeling this is all a lot more simple than I'm making it out to be but I guess that's what happens when a Joe Average (which at my sharpest I'm probably about 10 points shy of) goes head to head with a bunch of engineers.

Hey Hey! Don't be calling me dirty names like 'Engineer'! J/K

This dodgegarage mod simply keeps the boost pressure from building up under the BOV diaphram. At least this is the case if you don't hook it up for quick release mode. Which I don't. I like the stock-like feeling when it's not hooked up to boost pressure. In fact I didn't even go to the trouble of hooking up a hose barb to the new access hole.

First of all your plugging the small access hole in the bottom of the BOV so that boost pressure in the UICP doesn't push up on the diaphram. This removes any extra forces besides engine vacuum to work against the BOV's spring. This means the spring will hold more boost.

Second of all you need to add an additional access (or vent) to the under diaphram area. This is really just to allow the diaphram to move freely. It's kind of like having a small vent hole in a gas can to release vacuum build-up as you pour the gas out of the can through the large hole.

Hopefully that helps, but if not I'm sure that Nate can throw a couple engineering words at you like 'sampling' and the like.