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I am just wondering if anyone has instruction on how to properly "crush" the 1G DSM BOV so that it can hold more boost without leaking. Or at least if you could point me in the right direction and is it something I can do myself or am I going to have to send it off to someone??
 

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Good info

Check out the 1000+ questions already answered for DSM cars:
members.shaw.ca/costall/1000Q/questions.htm#O2sensorquestions[/img]http://members.shaw.ca/costall/1000Q/questions.htm#O2sensorquestions

Here you can find specifics on how to do what you're looking to do:

http://members.shaw.ca/costall/1000Q/answers-minor.htm#WhatisacrushedBOV

If you can't get to the link or find the info this is what is there:

What is a crushed BOV?
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Owners of highly boosted cars have discovered that the stock 1G BOV tends to begin to open too early. This causes a pressure leak in the intake system that limits boost. The valve tends to leak somewhat at lower boost levels, then opens fully when it's supposed to. This low-level leakage is the problem. The 1G BOV will usually hold pressures to about 22 psi, so this problem usually only appears on cars with upgraded turbochargers.

[2G owners have this problem, times two - the stock 2G BOV can just hold stock boost levels, and tends to start leaking at around 15 psi. 2Gers don't crush their BOV because it's plastic and won't crush. Instead, 2Gers often replace their unit with a stock 1G BOV to eliminate the leakage problem. This works until they too reach the limits of the 1G BOV.]

One DIY solution proposed to fix this problem is to crush the BOV. This means exactly what it says - stick the valve into a vise or clamp and squish it so it doesn't open as early. This is really a cheap & dirty method of increasing the spring force holding the BOV shut, and saves the operator from having to install an expensive aftermarket BOV. This techique can, however, restrict the amount of air that can pass through the BOV when it is wide open, making it a less efficient BOV, and therefore not as good as an aftermarket unit. All of this theory was explained by Todd Hayashi in his August 31/99 post on the subject. A follow-up summary post by Robert Mangus can be found here.

Although the technique is simple, individuals should use caution in applying it since various BOVs and crushing techniques are different. The essential technique is to crush the BOV so that it begins to open when 18-20 inHg of vacuum is applied to the reference port. Pristine BOVs will begin to open much earlier than this. Crushing should be done a little at a time until the BOV responds properly. Over-crushing a BOV may result in poor performance.

One opponent to this technique is Jim McKenna; he explains here how moving the BOV pressure reference solves the leakage problem. (Jim explains his original concept here.) Aaron Becker disagreed with the idea, while Warren Tsai supported it. As with most information available about this modification, this debate remains incomplete. Regardless, owners of stock turbochargers need not concern themselves, as the stock 1G BOV works just fine with stock turbos.
 
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