Dual Valve-- Forge BOV/stock BPV How-To+ pics

jeffmsp

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2003 MazdaSpeed Protege
ok, well first ill explain. as most forge bov owners know, the valve can sometimes cause stallling and on the highway, leak at certain rpms (for me I could NEVER cruise going over 125 km/h 3.5krpm) causing the driver to use the right foot like a lightswitch, constantly accelerating and decelerating the car, while the whole time the damn thing keeps blowing off causing tons of hesitation and poor mileage. To help remedy this, I first picked up a 3 way connector. It has a 1" inner diameter.

Connect one end to the hardpipe, then the end pointing down to the stock BPV and the one pointing straight to the forge BOV. Next put a 3 way connector on you vacume source. Make sure to get the vac line as close as possible to the stock BPV. Then make yourself at least a 9" vac line going from the tri-connector to the forge BOV. The point of this is to get the stock BPV to activate slightly before the forge BOV. A slight delay in the BOV is desired here thats why we use at least 9" of vac line. After 12" of line, I noticed the turkey starting to come back, so that means the BOV is too delayed. It may differ slightly for you/ If you hook them up to their own vac sources then the forge will open and vent all the air before the BPV even has a chance to recirculate some of the air.

(if you think you are smart and try to just run a long hose to your normal forge BOV setup so that it just doesnt open as much you arent going to like the outcome lol the dual valve is needed)

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I dont have any installed pics cause I dont have a digi cam now cause of my ex g-friend, (fu) but i might be able to get one later in the week. until then, look at the pics and think what it would look like lol

Now let me just say that this isnt perfect. If you accelerate and let off a huge pisssssst and then dont touch the gas and let the rpms drop it will studder a bit, however not as much as having just the BOV by itself. Mine is yet to go under 300rpm, but im sure it could happen if I blew off like 3 times in a row trying to get it to stall. The major improvement that I have felt is on the highway. It feels very similar to the stock BPV only setup, but when you need the throttle responce, it doesnt lag like stock.

Anyways, try it out and let me know what you guys think.

TTYL, Jeff
 
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well after my 1.5 hour drive to work, I cant tell you that this setup is a real improvement over just the BOV. The car runs like it should....seems like a first for a msp ;) somebody else wioth a forge try it, you will be happy you did
 
thx for the write up. I was wondering how long it would take for someone to do a multiple valve setup using a forge. I've got no hardpipes currently though. I really don't have any issues with mine, but your speed is way serious compared to mine. Peace
 
oh and the vacume source that you tap for the BOV/BPV will have a impact on the length of hose used. car is still liking the dual setup, is there anyone with a forge that tried it?
 
Possible to get an update on this? Maybe some installed pictures especially one of the 3 way connector... Thanx
 
ill try and take a few pics tommorow. Ive been running just one or the other recently since I havent had alot of time to make things nice under the hood. This setup would be rendered obsolete by moving your maf to the IC to TB pipe BTW
 
How would you want to moove the MAF there? I would have to cut a part out of my cold pipe... Not too fond of that...

Also while were in the subject, I bought my valve used. What kind of maintenance should I bring to it?
And does your's make a slight turkey and then a slight swoosh shound?
 
yep slight turk, then swoosh with the FMIC and pipes, lts more turk with stock pipes. As for maintenance, just lube it up when you get a chance. Ill try and get that pic for you, ive just been uber busy lately.
 
So to lube it, I'm guessing I should take it apart and just use a bit of regular motor oil? Correct me if I'm wrong.
 
jeffmsp said:
yep slight turk, then swoosh with the FMIC and pipes, lts more turk with stock pipes. As for maintenance, just lube it up when you get a chance. Ill try and get that pic for you, ive just been uber busy lately.

Jeff, I started to take it apart a while back for lube but I felt like I was going to strip the first allen screw I touched. I just stopped. Are they tuff to get off?Maybe I was just paranoid. Bump on the motor oil question. I can't remember what it looked like new. thx
 
I only had my camera phone so you might have to zoom in to see the BPV. The BOV also did not have a silicone coupling holding it to the T in that pic so you can get a better idea of how it works. Looks better with the silicone on.

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Thanx for the pictures, but when I zoom them we dont see very well. If you can try to get better ones it'll be greatly appreciated.

Let me know on how to lube it also.
 
Allen screws are on very tight. I'm trying with a bit of penetrating oil to see if it'll budge. I also tried to loosen them but felt like they were going to strip.
 
I was able to loosen the allen bolts. Wasen't easy though. Cleaned the whole valve and used grease to re-lube it. I also had a chance to mess around with different resistance springs. Yellow is good, but I get more turkey than swoosh... then I tried the green one with a metal spacer.. good also, less turkey but the best IMO is the original green spring. Too bad they dont make a softer spring because i'm pretty sure we'd get more swoosh.

Still waiting on the better pictures!
 
So today i switched over back to the stock bpv, because i was getting tired of the way my car was running on the Forge bov. If you get some better pics soon. Ill try your setup.
 
ok ok ill get em.i just got no digi cam so its a bit hard to get a good one.
 
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