induction help please

[davehg]

i hope someone can help me,

last night i fitted a HKS induction kit as per the instructions that came with it, all of the pipes are in the correct place etc but now i can hear the air pump (what ever this is) cut in and out. also when i let off the throttle i hear a woosh exactly like a dump valve. is this all normal?? do i need to tape over the old inlet hole (from the air box) in the front plastic box that also fits onto the intercooler??

any help would be much appreciated.

ps the only other mod to the car is a kakimoto back box.

[davehg]

does anyone have any ideas on this?

[Smifta]

Hey there I have an HKS induction, and they are a lot noisier than the stock airbox. Lots os whooshes and sucky noises. The kit came with the car, so I cant really help with installation, although if you post some pics I could let you know if it is like mine !!!

Hope that helps,

Alex.

[davehg]

its installed correctly but as you let off the throttle is sounds like a bov going off. is your air pump noisy when it cuts in?

[Smifta]

I guess the reason you can now hear BOV type noises (CRV) is that that it routes into your induction kit, and doesn\'t have any baffling like the stock airbox does. So I would expect that! It may also be your wategate dumping exhaust gas when you let up. I can\'t be sure about these noises as I have a Blitz BOV that it quite noisy on it\'s own!

I can\'t hear the airpump, but I plan on getting shot of it ASAP anyway (I don\'t have any cats anyway).

Some more techy types may want to chime in here!!!

Alex.

Originally posted by davehg
its installed correctly but as you let off the throttle is sounds like a bov going off. is your air pump noisy when it cuts in?

[davehg]

it just concerned me thats all as i dont yet have a bov but want to fit one, if its supposed to make this noise then there is no point in fitting a bov, but why wiuld i now be able to hear the air pump cut in.?

[MintyFresh]

it sounds like your wastegate.

[fro]

Originally posted by davehg
it just concerned me thats all as i dont yet have a bov but want to fit one, if its supposed to make this noise then there is no point in fitting a bov, but why wiuld i now be able to hear the air pump cut in.?

they\'ve got a bov as standard so you\'ll be able to hear that since it seems to blow back through the air filter, don\'t worry about the air pump noise, I had that with the cat and induction kit. It made a great Mooing noise :rollin

[davehg]

great thanks for your help guys, i was getting quite worried about it. oh and yes it does moo as well

[Phil Bateman]

I believe the noise is caused by excess air from the air pump venting back into the air filters. I have the Blitz kit and it was noisey but I have solved the problem. The air pump has an inlet pipe (the short 90° hose) and next to it  a much longer vent hose leading back to the filter.
I have fitted a restrictor in this hose and the "mooing" noise has stopped. I have used 7/8" o/d alloy bar with 3 x 3mm dia holes drilled through it.

Regards
Phil

[Martin]

so are you getting much gains from it Dave?

[davehg]

to be honest i havent noticed ant difference.

[eatmyrx7dust]

problem with the rx-7 and induction kits is that once a kit has been fitted it may be more free flowing but the extra air it draws is hot from the engine bay. After I fitted mine, I made a heat sheild around the filters and ducted air from the open air inlet duct onto the new filters. Having the apexi pfc I noticed a 3-5 degree drop in intake temperature after doing this.

PS you can buy cheap ducting as used for tumbledryers. A lot cheaper than automotive ducting and you can buy it from B&Q.