Does anyone have a exploded diagram of the stock DV...does the small amount of crushing/compression of the internal spring really help increase spring force to keep it shut better?

Particularly interested in the crushed area to where the internal spring sits

 

curious myself... BUMP

 

so far, it sounds like snake oil to me

 

Yes. You can verify this by applying a vacuum to the top port of the DV. Each little bit you crush it requires more vacuum(in Hg) to crack the valve off its seat. Thus crushing increases the springs force. I wouldn't waste my time with it though.


If you're looking for a solution to a better boost holding DV with stock like driveability, consider this option. https://www.evolutionm.net/forums/sh...d.php?t=260029

 

To crush the metal, MR DV in a bench vise, try this method: Place a 1/2" thick piece of wood on one jaw of your vise to prevent damaging cast aluminum. Place a socket with a 1" outside diameter on the top of the DV, place in the vise and tighten just a bit and it'll "crush the top of the DV. Don't overdo it, though. I think I went too far, LOL

 

EDIT: Sorry, I double posted.

 

i have done this mod. i thought there was a slight gain, but i would try something else.

if you crush it to much, then you reduce the amount of travel the valve can open.

dont ruin the mr valve.

once you crush the bov, you cant get as much money as you could for a un-crushed.

i am looking to get a spring that has a higher preload & rate. i cut the top off a mr valve, i plan on making it adjustable.

i measured the mr bov spring pressure @ various lift's, but i have misplaced that paper, since i recently moved

i ran other bov's & although i like the boost response you can get from a high preloaded bov, i dont like the low th/hi boost venting characteristics associated with those bovs. none of the adjustable bov's had a pressure port on the bottom side of the bov diaphram which helps reduce the bov openingn/closing/opening abruptness = bucking effect.

by crushing my bov, i increased the static bov opening pressure of the bov from ~9 psi to 11psi by crushing ther bov. that pressure was obtained by only applying air pressure to the bottom side/valve side of the bov.

my plastic bov would leak @ ~6-7 psi.

 

I don't think SlowCar is asking how to crush the DV but your explanation on how to do it is very creative.

His snake oil comment leads me to believe he has doubts that crushing the DV yields any real benefit, e.g., holding boost better

 

m80 or grenade works well.