EvoInGR

I think if the factory EVO BOV is plastic, just like the 95-99 dsm BOV, it is in need of an upgrade. Why do 95-99 dsmers upgrade to a metal BOV then? Because their factory plastic BOV is leaking above 14-15psi... If someone would post some good pics of the EVO BOV we should be able to see what the deal is. Also, as mentioned earlier, Dave Buschur switched a 1stGen BOV on his evo and gained some HP, simply because boost was air tight in the high RPM, not bleeding off as it would appear the stock BOV does. This may be adding more strain to the motor, as every last PSI of boost is getting forced in, maybe Mitsu engineers WANTED this slight bleed-off so as to ensure long term safety of the motor at the expense of a few HP that an upgraded BOV will produce. For an unmodded evo though, a new BOV is not that necessary. I would get one after I got full exhaust, bc, IC hard pipes, and some fuel/ECU modding.

EvoInGR

I tried "cushing" my 1stGen BOV once. Ended up in the trash after "crushing it too much" and it didn't open at all. DO NOT CRUSH YOUR 1G BOV. Total hackjob, waste of $. If you're going for major high boost get an HKS or Tial.

ShapeGSX

There is a tried and true way to crush a 1G DSM BOV. It involves a vacuum pump, and a vice. If you do it wrong, you can make the BOV into garbage. If you do it right, it works every time.

There is an even better way of making a 1G DSM BOV seal, though. It involves some electronics, though.

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

EvoInGR

Huh, that link is not working for me, and I am interested in ways to make the 1G bov seal better. Other than crushing ofcourse, I will never be doing that again.

ShapeGSX

Hmmm, yeah, Gary's site is down. There are other pages detailing the mod, but I used Gary's method. Search for "mahon bov" on www.lycos.com .

Basically it involves drilling a hole in the side of the BOV flange and bringing the "helper" port to the outside. In stock form, the helper port sees the same boost that the valve does. But if you let it see atmospheric pressure, the BOV simply will not open.

So the basic operation you want is for this port to see atmosphere while you are wide open throttle. And at all other times, you want the port to see pre-throttle-body air pressure.

There is a good 3-port solenoid for this with the Borg Warner part number EGR201. You can get it at www.carparts.com for about $20. Then you wire up a switch to activate the solenoid at WOT. You could alternatively use a pressure switch to switch the solenoid when a certain boost level is reached.

You can buy a 1G DSM BOV with these mods here:
http://www.dejontool.web.aplus.net/dsm-misc.htm

Look near the bottom of the page. Personally, though, I like doing my own work and saving some money.

This port that you add to the 1G DSM BOV is the same port as on most aftermarket BOVs. If you want a 2 port Greddy BOV to operate correctly (hold very high boost, yet not cause compressor surge from being adjusted too tight), you will also need a solenoid setup like this. This isn't widely known.

Now where is that guy who blocked all of my posts because he thought I wasn't contributing anything useful?