Hello everybody!

I have recently bought a Blitz SUS intake, but the instructions are in Japanese, and the pictures are not very good as well. I figured out where all the brackets go, but I am unsure as to which lines the aluminum 'plugs/silencers' go into. If I compare them to the air hoses on the air pump and the ACV, the inside diameters of the hoses seem too large for the silencers - but the BOV and CRV hoses look about right.

Assuming these are meant for the BOV and CRV hoses (the crude diagram seems to indicate these as well, but in mirror image) is there any potential danger here in forcing the valves to discharge through the little holes instead of the regular hose diameter? Can anybody verify which hoses these are supposed to be installed in, or are the majority of you going without them altogether?


Jon
'93 Touring
'85 GSL-SE

 

Anybody?

 

^bump^

 

They are just silencers. Most aftermarket intakes have something like that. It's to quiet the venting air that is released through those valves.

There is no harm. Try it without them, and if you don't like the sound, you can add the silencers.

Adjustable aftermarket BOV's work in a similar way. You'll have adjustable holes to vent the air through. Smaller = quieter...

 

I had the instructions translated. Well just the word "silencer" anyhow. He told me they were for the BOV & CRV but some guys on here sware they are for the air pump because of their Apexi instructions. I think the picture is possibly reversed. I don't understand how there is any purpose of silencing the air pump, it sucks air and I think restricting it may damage it.

 

Thanks for the replies, guys. GoRacer, do you still use the air pump, and if so, do you have the mooing sound? What are your mods? And here's another one - how much louder is the intake going to be with the SUS on? I've never heard an FD with a cone type intake before, only ones with the M2 CAI.


Jon
'93 Touring
'85 GSL-SE

 

But now I like it. You can set off cheap/crap alarms. It is a throaty but somewhat metalic low noise if that makes sense. I tried to match the noise with the MOO sound but not sure if it's a MOO. That may be the noise on low RPM's and/or Vacuum.

I do not use the silencers, I like the BOV noises!

I do use the air pump, even though I have the Greddy kit to bypass it. The race shop (don't want to put them down) told me they would not bypass the air pump and forced me to buy a used one (taken off of someone elses car) for $500.00, so I bent over ...but they will install a mid pipe

The M2 has the BOV & CRV lines going into the box so the sound is muffled.

'94 Touring
Pettit ECU @14lbs
Blitz intake
Greddy SMIC & SP exaust

 

Well, I got everything together and ran the car without the silencers.....sounds like crap at lower RPMs (above idle, but below air pump shutoff at ~3250)....kind of like a large piece of plastic dragging the ground....I am assuming this is the dreaded 'moo'. I have been working on a translation of the instructions, and from what I have found so far, there is no reference whatsoever to the BOV or CRV. I now am about 90% positive that the silencers are supposed to go into the ACV and air pump hoses to quiet the moo. I believe they want you to put in two to prevent damage to the system. I have been thinking about this all weekend. If you restrict the ACV from being able to remove all the air that the pump is feeding in, there will be excessive backpressure in the system. This might be more dangerous than if the pump inlet is restricted as well, evening out the input/output volume relationship. A good example to look at is Pettit's intake - they use silencers on both the air pump and ACV hoses. If this theory is true, however, I am left to wonder why the Apex intake does not include a second silencer for the air pump. I also wonder if there is any tangible effect from the slightly decreased air volume with respect to the mixture under the above RPM conditions. I guess it won't hurt much, maybe run a bit too rich. Well, that's all for now - I will let you know if I make any breakthroughs. Hopefully we can get to the bottom of this silly 'moo' noise mess once and for all.


Jon
'93 Touring
'85 GSL-SE

 

The verdict is in -

I called Blitz direct and they said that the silencers definitely go in the air pump and ACV hoses. They also stressed that there have been no known air pump failures due to the silencers. After I got off the phone with them, I put them in, and sure enough, the car sounds great. No mooing. The only noises I hear now are the BOV, CRV, and the louder intake sucking noise on throttle. Life is great again!

Happy Rotoring!

Jon
'93 Touring
'85 GSL-SE

 

I will install mine tomorrow then!

 

ur so CALLED MOOing noise..passed as a V8 for me....

 

I installed the pills/silencers in the hoses to the air pump and the other deal. I still have my BOV whoosh noises (woohoo) but the dreaded, droning moo is all gone "yippie"!