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Old Nov 18, 2007 | 04:12 AM
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Whats this for?

Well i got my car serviced yesterday. The mechanic told me there needed to be a plate under the intakes, i didnt know what he was saying so i just trusted him and let him put one in. What is it for? Is it a heat shield from the turbos or something?







Also at what RPM should i hear the BOV?



Will
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Old Nov 18, 2007 | 05:26 AM
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they probably did that so your cool air coming accross in that black plastic ducting didn't dump straight out the bottom of the engine bay. The car would not have blown up because this was not there but it is a good idea.

The BOV is not rpm dependent. It works when you let off the gas pedal and there is positive pressure in the intake tract. It opens when it sees vaccum from after the throttle body and releases the air in the intake. So it is more pressure dependent than rpm. If you are still running the twins in stock sequential fashion you should here it whooosh pretty early, as the twins build boost rather quickly off the bottom.

Hope that helps a little
Dave
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Old Nov 18, 2007 | 06:00 AM
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i have no idea why he put a shield there? should of put it to the left of the intakes cause the engine, rad, and intercooler throw heat twards that area. if i was you, i might take it out and get or make one for the left side. pretty sure thats blocking some cool air comming from the duct and beneath the car.

i hope you didnt have someone install those intakes for you...?


^^and like that guy said, its not rpm based. it relieves pressure when you let off the gas. the higher the rpm you let off, the louder it will be. look at your intakes...one of the lines that plugs into the intake pipe will be the bov that gives off a noticable sound.(it will have a brown bov actuator on it) just unplug it from the intake. it will be one of 2, so just find out which one it is.

Last edited by 4CN A1R; Nov 18, 2007 at 06:08 AM.
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Old Nov 18, 2007 | 06:07 AM
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Originally Posted by 4CN A1R
i have no idea why he put a shield there? should of put it to the left of the intakes cause the engine, rad, and intercooler throw heat twards that area. if i was you, i might take it out and get or make one for the left side. pretty sure thats blocking some cool air comming from the duct and beneath the car.

i hope you didnt have someone install those intakes for you...?
Whats wrong with the intakes?
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Old Nov 18, 2007 | 06:12 AM
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Originally Posted by BigWillieStyles
Whats wrong with the intakes?
nothing, they look great...i mis-understood. i thought you took it to a mechanic to get them put on and in the process he said he had to put on the shield. but i just saw that all you said was the car was being serviced....and so on
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Old Nov 18, 2007 | 06:16 AM
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this is the one you need to disconnect to hear the bov:

edit:

nvm, i tried to take your pict and crop it. but its not working, sorry

anyways in your first picture the bov you can disconnect is the closest to the bottom of the page. thats wat gives you the bov sound

Last edited by 4CN A1R; Nov 18, 2007 at 06:25 AM.
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Old Nov 18, 2007 | 07:24 AM
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That plate isn't going to make it a cold air intake.

But maybe it would be enough to keep rain water from splashing up onto the filters?

Seems kinda pointless since it looks like you have a stock undertray installed.
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Old Nov 18, 2007 | 07:30 AM
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anyways in your first picture the bov you can disconnect is the closest to the bottom of the page. thats wat gives you the bov sound
Thanks mate, the service was done by a Rx7 workshop JUDAS here in Japan. But evenso, im not convinced its a good shield and im going to take it to a different rx7 workshop next time.

Ive got a BOV sound, but being as paranoid as i am, i thought that after the service it wasnt as loud.

Is this what your talking about?

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Old Nov 18, 2007 | 07:48 AM
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sure is

just to be safe, if you take it off i would cap the end on the intake. just so nothing(bugs for instance) will be sucked in it.
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Old Nov 18, 2007 | 08:00 AM
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Originally Posted by dgeesaman
That plate isn't going to make it a cold air intake.

But maybe it would be enough to keep rain water from splashing up onto the filters?

Seems kinda pointless since it looks like you have a stock undertray installed.
Yeah, that was exactly my thinking too. Unless the undertray was gone and the mechanic was worried about water ingestion....
Unless perhaps there is an issue with fluctuating air pressure across the intakes?
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Old Nov 18, 2007 | 08:52 AM
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ok guys it seems ive been left in the dark, i dont speak great japanese, apparently my gf said it was to stop the popping of the exhaust or something....

If anything i just wasted 100bucks, nevermind
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Old Nov 18, 2007 | 08:57 AM
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your mechanic must be thinking that it is better to isolate the intakes as much as possible to lower the intake temps.
the change after installing the plate would be minimal @ best.

the Bov will discharge when there is trapped boost pressure.
the throttle plates close when u let off the throttle leaving the boost air trapped with no where to go. the bov opens to let this air out of the system so there is no back pressure on the turbo compressors, leaving them stress free and ready to spool again.
hence u will only here the bov when u let off the throttle while the car was making boost pressure. rpm is irrelevant

Last edited by Smitter; Nov 18, 2007 at 09:11 AM.
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Old Nov 18, 2007 | 10:41 AM
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Thats pretty cool that mechanic installed that shield. Ask him to also put a left side shield on as a heat shield. Then you'll have a more "cold" air-intake. Good luck with the BOV - waste of money IMO.
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Old Nov 18, 2007 | 10:43 AM
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Originally Posted by MrNizzles
Thats pretty cool that mechanic installed that shield. Ask him to also put a left side shield on as a heat shield. Then you'll have a more "cold" air-intake. Good luck with the BOV - waste of money IMO.
He's running the stock BOV. no money wasted
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Old Nov 19, 2007 | 05:12 AM
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Originally Posted by GoodfellaFD3S
He's running the stock BOV. no money wasted
How do you know im running stock item? Did they make HKS BOVs as stock items? Im completely clueless, the last owner did a few mild mods that im still finding out about.

Im going to take the metal thing out, i think its causing higher temperatures. But there is brace he installed on the side, i might use this to try and make a custom heat sheild.

Last edited by BigWillieStyles; Nov 19, 2007 at 05:24 AM.
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Old Nov 19, 2007 | 12:32 PM
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that plate he installed would block hot air from the rad fans. u might be best to leave it. otherwise when the fans kick in they will pull air right towards your intake
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Old Nov 19, 2007 | 06:35 PM
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The plate is obviously to prevent water ingestion...
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Old Nov 19, 2007 | 06:45 PM
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Originally Posted by BigWillieStyles
How do you know im running stock item? Did they make HKS BOVs as stock items? Im completely clueless, the last owner did a few mild mods that im still finding out about.
HKS did not make the stock BOV to my knowledge. How he knows you're running a stock BOV is because you're still using stock plastic IC pipes and a stock IC(unless you have a Greddy Elbow and ghetto rigged stock plastic pipes...).

Also, in the picture of your intakes, the rubber hoses I've circled belong to the stock recirculitory BOV system. the second circle is one of the stock BOVs.(for all intents and purposes, though they technically have different names)

Attached Thumbnails Whats this for?-img1947smallpj1.jpg  
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Old Nov 19, 2007 | 07:28 PM
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Isnt this my BOV?

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Old Nov 19, 2007 | 07:41 PM
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Originally Posted by BigWillieStyles
Isnt this my BOV?
No, that's an air filter for the air pump.
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Old Nov 19, 2007 | 07:47 PM
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no thats a hose that i believe either sucks air or blows it out(i forgot since i dont have it anymore).. its for emissions, that is connected to the air pump IIRC
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Old Nov 19, 2007 | 07:50 PM
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Originally Posted by FD3S2005
no thats a pipe that i believe either sucks air or blows it out.. its for emissions, that is connected to the air pump IIRC
the piece he circled and added the arrow to is an air filter. it comes with that HKS intake kit. It's attached to a rubber hose which I believe attaches to the air box stock.

In either case, it's not a BOV.
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Old Nov 19, 2007 | 09:15 PM
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Are ---- thanks guys, im so lost with this turbo stuff. I will have a look for the BOV tonight. Where is it located? Can you see it in this pic?



So i probably have a stock BOV. But its quite noisy, i can hear a big woosh. Is this normal, ive only ever driven one other FD and cant remember the sound. Anyone have a sound file for the stock BOV?

Last edited by BigWillieStyles; Nov 19, 2007 at 09:17 PM. Reason: adding a pic
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Old Nov 19, 2007 | 09:50 PM
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Originally Posted by BigWillieStyles
Are ---- thanks guys, im so lost with this turbo stuff. I will have a look for the BOV tonight. Where is it located? Can you see it in this pic?

So i probably have a stock BOV. But its quite noisy, i can hear a big woosh. Is this normal, ive only ever driven one other FD and cant remember the sound. Anyone have a sound file for the stock BOV?
Look back at the circles I put in your other picture. I circled the BOV that was visible and I circled the hose that attaches to the other BOV. follow that hose, and voila...BOV.

Yes, it's perfectly normal to get the "woosh" sound when you don't have an air box. That's a bi-product of a BOV..they go "woosh"
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Old Nov 19, 2007 | 09:54 PM
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Thanks heaps, i really appreciate that.

Im going to try and remove the metal thing this weekend, i think that it might be blocking the fans
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