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Discussion Starter · #1 · (Edited)
Most of this is on my intake/charcoal can. thread, but I figured I would make this seperate post so people who arent interested in that thread can refer to this :)

The 1G DSM BOV sounds excellent vented or recirc'd (sounds VERY similar to the GReddy Type-S BOV). Vented you get a long whiney whistle, and recirc'd you still hear it (just not as loud), but also get a nice loud hollow "goooshhhh". I personally like the sound better recirc'd as well as the smooth driving when still using the AFM.

Just FYI: The 1G DSM BOV can hold boost efficiently at WOT till around 15psi, then it will start to leak (it also does leak SLIGHTLY at idle and light throttle, but the valve stays shut at WOT). You can however get it to hold up to 22psi efficiently and not leak even at idle by doing one of two mods:

1. http://www.thedodgegarage.com/turbo...od.html
(the one I consider the less-needed and a bit overkill mod).

and

2. Is to "crush" the BOV by crushing the top hat of the BOV (near where the vacuum nipple is) to create a stronger vacuum and to keep the valve seated longer, and to close quicker after release. This is one of the common "free mods" that are done with the 1G DSM's. You must be careful doing this, as if it is crushed to much, the valve will not open properly causing compressor surge which can possibly/eventually ruin your turbo.

I am stating this info because I think the 1G BOV is a great stock BOV and it is dirt cheap (can be had for $30-$40 used on most DSM sites). Another benifit for those of you who eventually want a GReddy Type-S, is that the 1G BOV flange is compatable with the Type-S. You simply drill the holes for the screws in the flange and cover the old ones, thats it. The flange otherwise fits directly on the Type-S.

I also wanted to point out that I did notice some gains in the small pipe and 1G DSM BOV as well.

- It obviously holds boost pressure better
- Its obviously louder (vented as well as recirc'd)
- Noticed a bit of top end difference as well as accel. (probley because of the hardpipe).
- Also noticed louder spool even before my homemade intake. With the intake and BOV recirc'd, the turbo spools about as loud as I have heard on a modded MKIII with turbo back exhaust and 10psi. Cant wait to get exhaust and hear this puppy really breath. Here are the pics:









I can post more info for anyone interested. Let me know what you guys think ;)
 
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Discussion Starter · #2 ·
i have a 1st gen DSM BOV and i have heard that if you crush the top 1mm it will hold 12psi with no leaks. how far will i have to crush the top to get 22psi?
 

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I ran 18psi with the 1st gen dsm BOV in my 97 eclipse. Its a very stout piece. Extreme Motorsports were using this BOV in there 9 second Talon.
 
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Discussion Starter · #4 ·
my friend has his cap crushed 1mm on his 92 DSM BOV and at 14psi his started to leak. how did you get yours to handle 18psi with no leak?
 

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Not sure, I never new they leaked to begin with. Its a recomended upgrade for 2nd gen DSM's.
 
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Discussion Starter · #6 ·
2G DSM BOV's are POS plastic pieces that leak at idle and WOT. A BOV should be one of the first mods to a 2G.

Dlos: The stock 1G BOV will hold 12 psi as is. If you can build or custom fab an intake so you can recirculate it, you will have no problems what so ever. I built my intake from plastic ABS pipe so its very easy. Crushing the 1G BOV 1mm and you should be able to hold 18-22psi with no problems at all.
 

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Supra Dupra
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go to www.vfaq.com
it's a DSM site, but I believe it tells you how to mod the BOV to hold higher psi. I did it when i had my Galant VR4...but eventually went to the HKS SSQV. I think the aftermarket valve is better. DSM is known to have idle problems if the BOV is vented, even with the crushed/modded stock 1G BOV. When I used the HKS BOV, my idle problem went away as it stayed shut. BTW, would the MKIII have idle problem similar to the DSM if the BOV is vented from running too rich????
 
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Discussion Starter · #9 ·
Venting mine the past week was okay. I did notice the drop in rpm when you push the clutch in or pop putta gear on decel. and I also noticed it did drive and shift a lil bit rougher. Now that the 1G BOV is recirc'd, it drives like stock.

Keep in mind that the 1g bov, as well as some other stock BOV's are actually made to leak slgihtly at idle and light throttle. Some stock bov's (such as the 1G BOV) can easily fix this. www.vfaq.com does not have the crush mod on there (at least I cant find it right now, but Im doing a half ass search), but they do have the crush alternative where basically you add another vacuum source (like the Type-S) to make the vacuum close the valve faster after opening, as well as make the valve seat tighter (see my first post for the vfaq link).

And any aftermarket BOV (especially the HKS SSQ-my favorite BOV) will be better than an OEM BOV, but the 1G BOV is a great mod for the money it would cost to convert.
 

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Supra Dupra
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I have a crushed 1G BOV left over from my old Galant VR4 if anyone is interested.
 

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Also sorry to hijack but I'm looking for the intake/charcoal can thread you mentioned Dieselboy. I can't seem to find it searching.
 

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DLosMA70


You might have crushed it too much, or maybe even cracked the diaphragm, cause i've had one before and cracked it held a lot less boost.

I can get my hands on one way check valves for guys running 1g bovs, i have this one on my car after putting the 1g bov on, w/o it when i vented the car would stall, but the check valve would vent out and close so that no air gets sucked back in
 

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I'd love to see more pics of this, I'm considering doing it soon. Need to source a hard pipe, and I don't think 91Supratium has sold his BOV yet, so I may be getting it.
 

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Supra Dupra
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fstlane86 said:
I'd love to see more pics of this, I'm considering doing it soon. Need to source a hard pipe, and I don't think 91Supratium has sold his BOV yet, so I may be getting it.
Still have it....I would post pics, but having problems with my digital camera. Should have it up in 24 hrs. from now. :D
 
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Discussion Starter · #18 ·
I will most likely have this pipe and BOV up for sale here in the near future. I plan on making another pipe with the HKS SQV off my Eclipse GSX. I may just sell the pipe so someone can use the 1G BOV or the GReddy Type-S BOV if they so desire, but I would prolly sell as a whole if someone was interested.

If anyone needs help or more info, gimmie a holler :)
 

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Ahhh, DAMNIT!! Exactly what I need, and I'm stuck fixing the body of my car myself, and everything has to be put on hold until I can get that done.

When do you think you will be selling it, and for how much for both the pipe & BOV.
 
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Discussion Starter · #20 ·
Well, I would probley sell anytime actually. Id like to get either $80 shipped, or Id do $50+ a new HKS flange shipped.
 
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