ok guys, i just finished my custom intake which is basicaly identical to the hks racing suction.

Anyway, i just put a small k&n on the air pump and i knew i would get the mooing sound but MAN!!! it is so loud... i can't drive like that, everyone thinks i have an hidden dragon under the hood that is waiting to come out.

what have you guys done with yours open intake? Is it different when it goes behind the air filter? i can't beleive that people can drive with that sound. I suppose that unplugging the air pump is not a good idea since i still have my main cat.

please tell me something.

man i love this board, thanks a lot

puma

 

Apexi Power Intake has a restrictor pill that goes in the hose to the air pump.

Basically a chunk of aluminum that fits in the hose with a small hole drilled thru it to reduce the flow into the air pump.

Sounds like you have a relatively free flow of air to your air pump.
Hope this helps.

 

yep that really help because i drove my friend's car and he has that apexi intake and i didn't hear that sound.

yes i have a free flowing intake on the air pump, i have a small k&n breather right on it.

maybe i should put some restriction there...

 

I recently did a similar custom intake job and currently have the "Moo" sound but mine isn't horribly loud. I still plan to fix it ASAP though. Someone on the forum had mentioned that you can purchase a small lawn mower muffler from Home Depot to get rid of this sound. I plan to check out what they have and see if this is possible. Thought you might like to check it out as well and see what kind of luck you may have with it.

 

do away with all your cats, get dp and mp - if you've got a dragon under the hood, you need to let him shoot his flames!!

 

Put a pair of cattle horns on the hood like the guys in Texas do.

 

I put a lawn mower silencer but it was still quit a moo
so I put some steal wool in to the silencer and no moos anymore.

 

is it ok to plug it up completly and not put on the small k&n breather filter?
the reason i ask is that when i had my pettit intake i had a breather on there and there was mooing.
now i have the arc intake and it plugs the hose up, but no mooing.

 

You guys have it all wrong.

Who wants a ******* lawnmower muffler under their hood?

Go to the parts store and get a valve cover breather for an american car. They should have a large selection just find one with an inlet that is the same size as the airpump hose.

Mine is black plastic and is a circle that is about 2 1/2" round. Its not very noticable and I'm sure that it looks alot better that a muffler. You don't hear any mooing.

It cost me like 89 cents

 

Thansk for the info 93 R1. This sounds like a better option than the lawnmower muffler. I'll check it out and give it a try.

 

I have a custom CAI also. At first I had the airpump outflow(metal tube to the right of the upper intake coupler)venting to the engine bay and the mooing noise was horrendous! The out flow from the airpump is making that shitty mooing noise, not the airpump intake.

What i did was stick about a foot and a half of 1" hose that I had laying around on the tube and run it down toward the gap between the radiator and the body. The noise practically all but went away.

my .02

 

are you talking about the top of the two metal tube that are attached to the lower intake manifold? that would be where the sound come from? i put a small k&n breather there too.

 

Okay, maybe I'm just totally confused, but are you talking about the noise that the air pump makes? If so, then just unplug the air pump.

 

That moooing sound doesn't come from air pump, It comes from that pipe next to the air pump. It's one inch pipe and the restrictor pill that comes with apexi power intake goes in there. I didn't get the pill when i purchased my intake so i made one myself. I just bought one inch of pluged metal tube and drilled small hole in it and put it in that hose. The mooing sound completely went away.

I hope that helps you guys.

 

hmm well i guess i'll try that

the problem with unplugging the pump is that it won't work, making the main cat clog itself

 

Oh Great. That's probably why I'm not getting full boost now. Oh well, the midpipe and Home Depot boost controller is going on next week.

 

Where does that pipe go?

 

I dont' know where that pipe exactly goes, but you should search that's how i found out hot to quiet that sound and how the sound is coming from that pipe, cause i guess it doesn't want a lot of air or something.

 

You know, I guess i'm crazy. I don't mind the moo noise. It confuses people, and makes them a little scared to go. Only a select few(non rx7 owners) knew what it was when they heard it .
I know.
I'm wierd....

 

Yup, I am. That pipe is normally connected to the OEM airbox via a one inch, 2.5' long hose. and with out it it makes the mooings noise really loud.

I also had a breather element on it for a while, but figured out that it was an out flow and didn't need a filter.

 

I took my non rx7 friend for a ride today and he asked if something was wrong with the car when he heard it. Not the impression I'm shooting for. Of course I responded "hmm maybe lets see" and took him up past 100 with him gripping the grab handle the whole way. After that he stopped asking questions about the car-and everything else.

 

That'll learn em'.

 

you see, that is exactly why i want to remove that sound, not for me, because i know it is armless.

i already have trouble explaining what a BOV is when they hear the sound, if i have to explain what is an air pump on top of that...

jpandes, thanks a lot, that is the kind of info i needed. i'll try that out. I too though air was entering from there but thinking about it and looking how the air box is made, it makes sense. Otherwise, the air coming from there would have not been filtered.

thanks again

puma

 

Another solution is to get rid of the airpump. No more mooing.

 

I have had the moo for awhile, I actually got used to it.