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- MSP 1145
x2 it makes sense.
xDJ DUBx's 03.5 Pure White LX-T
- Thread starter xDJ DUBx
- Start date
x2 it makes sense.
Laser Blue
Member
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- '03.5 Mazdaspeed Protege / Laser Blue Mica
Low boost is the issue.... Dub had the turkey before the CAI... he just couldn't hear it. The backflow wasn't bottled up... it just escaped through the open turbo. Now its bottled up and wants to get out and the stiff spring in the BOV lets it open when the boost is greatest, but as the pressure reduces the stiff spring is closing the BOV before all of the boost pressure is completely gone. So... gobble gobble. If Dub had higher boost pressure it would overpower the spring and hold the gate open to allow more boost gas out. So again, weaker spring or secondary relief device.
Wagonbacker9
Member
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- 2004 'Hoe
its got everything to do with fluid dynamics, and my bet, nothing to do with amplified sound.
I look forward to being proven wrong or right. either way I'll be happy.
if you ran more boost, it would just close at the same (lower) boost level after releasing more air... so that would functionally change very little..
I look forward to being proven wrong or right. either way I'll be happy.
if you ran more boost, it would just close at the same (lower) boost level after releasing more air... so that would functionally change very little..
Laser Blue
Member
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- '03.5 Mazdaspeed Protege / Laser Blue Mica
Dub, when you remove the filter the gobble will be gone, for the same reason it was gone with no CAI at all. But you don't wanna be running without a filter for too long.
Stock BPVs are a dime a dozen around here. SOmeone around you prolly still has one they're not using. Run it between the CAI and cold pipe and I'll bet you the gobble is gone.
Stock BPVs are a dime a dozen around here. SOmeone around you prolly still has one they're not using. Run it between the CAI and cold pipe and I'll bet you the gobble is gone.
Wagonbacker9
Member
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- 2004 'Hoe
what reason does the "no cai" have in common with "no filter"? and now its the filter? before it was alloy pipe. I'm confused.
my bet is that the added restriction on the intake of the filter is changing the dynamics of the air in the entire system, and having that restriction is creating a partial vacuum on the intake side of the compressor, which fluctuates when the BOV suddenly releases pressure upon the TB closing. that partial vacuum is causing the pressure wave to be out of balance where it was in balance before.
and you get: compressor surge.
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Laser Blue
Member
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- '03.5 Mazdaspeed Protege / Laser Blue Mica
Dub said tomorrow he was gonna remove the filter to see if that changed anything... and yes it will. But that would prove it isn't the pipe amplifying turbo noise... but I already know its not that.
Wagonbacker9
Member
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- 2004 'Hoe
oh thank god... i'm not the only one that thinks that sounds bogus?
Laser Blue
Member
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- '03.5 Mazdaspeed Protege / Laser Blue Mica
I had the turkey with my WeaponR intake. I cut off the nipple connecting it to my stock BPV and removed the BPV. I welded a 1" diameter nipple onto the SRI and cold pipe and used 1" hose to connect them to my new Boost Sciences RDV which replaced the stock BPV. Suddenly, the turkey was gone, even though the long aluminum SRI pipe was still there.. Its all about removing restrictions that were keeping boost gases from escaping.
Wagonbacker9
Member
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- 2004 'Hoe
and this 1" pipe is a large enough volume to properly release enough air to alleviate the pressure wave that would have otherwise caused surge. wonderful, so we agree then. lol
Laser Blue
Member
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- '03.5 Mazdaspeed Protege / Laser Blue Mica
I think you're very close Wagon, but I think its even simpler than that. If all the pressure can escape through the relief valve then theres no pressure left to create compressor surge. And the little that does remain is distributed into the intake pipe. With no filter that pipe in effect becomes endlessly long and gives all the leftover gas an easy place to go. Add a filter, especially with a very short pipe, and there isn't room to contain much extra pressure so it backs up into the turbo (compressor surge).
Wagonbacker9
Member
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- 2004 'Hoe
so dub, are those plugs working for you now that all your issues are worked out?
Wagonbacker9
Member
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- 2004 'Hoe
he's not recirculating... so nothing goes to the intake pipe.
Laser Blue
Member
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- '03.5 Mazdaspeed Protege / Laser Blue Mica
Yes we do... but remember that I had to go to a 1" system because I have no BOV. For Dub, using a stock BPV will prolly be enough because most of his pressure is already released through his BOV.
So, to summarize.. lighter BOV spring and/or BPV.
Wagonbacker9
Member
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- 2004 'Hoe
haha thats what I like to hear... I will likely switch to the plat for my next set.. I checked one (using copper now) and they're already starting to burn up.
i heard that someone was sayin they were too long causing your #4 issue... i was very relieved to hear that was total bulls***.
i heard that someone was sayin they were too long causing your #4 issue... i was very relieved to hear that was total bulls***.
Laser Blue
Member
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- '03.5 Mazdaspeed Protege / Laser Blue Mica
HeeHee... ooops... you're right. So lighter spring. Or add a BPV... or remove the turbo.... JUST KIDDING!
Wagonbacker9
Member
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- 2004 'Hoe
ok, adding a BPV will put more air (easier) between the turbo and filter.
my vote is do it simpler: get a less restrictive filter and keep the system as simple as possible.
both ways are trying to accomplish the same thing, I just see one as VASTLY easier.
