Another...Drilled Airbox

[bigndaft]

I know its been done to death but after reading all the threads i bit the bullet last night....it took about 30mins and was well pleased with me neat job. I threaded the hose under the battery and was easy to poke down to the vent next to the fog light. I got the 60mm hose from my local auto parts shop which stretched and bent and stayed in position, he let me have nearly 3ft for £8. took the pimpmobile out for a blast and it s hard to tell if it made any difference although it did seem to pick up quicker.

[rs_andy]

I drilled mine a few weeks ago and to be honest didn't feel that much different but she makes a lovely growl under acceleration when cold.

[SaffronC70]

Cold air feed - the way to go - no OTT swiss cheese jobs though.

Chris

[M44K TS]

can you still hear the recirc valve with a drilled airbox?

i recently changed froma cone filter (cause of my problems) to standard airbox with a pipercross filter and miss the recirc noise

[SaffronC70]

I've done exactly the same Mark, live without the noise - I know it's hard to though !

[GATHY]

silly idea
couldnt we run some ducting from the air con into the air filter.
could work like ajustable boost colder fast. warmer slower.lol
you try it the let us know how you get on

[M44K TS]

it sounded great with the cone filter and no under bonnet sound deadening pad thingy. Ah well, i guess i'll have to get a bailey dump valve kit then

[BagR]

this was officially the first bit of tinkering i've done with the R . Was bored on Sunday afternoon, so went out and took the airbox out, drilled 1 hole in the bottom (not into swiaa cheesing it tbh) and fed a K&N pipe i had laying around, from the vent beside the foglight, up under the battery.

Haven't actually driven it though, as i was blocked in by the wifes mini lol

next its moving the horn...

[siamblue]

Hi Bag what bore hose did you use?


Gary

[BagR]

umm, whatever came with my old K&N... Think its 60mm. Should the bore matter so much when i'm just moving more cold air to the area?

Andy

[p fandango]

BagR, i used the same type of pipe on BT & it collapsed under WOT (choking the engine & scaring the sh*t out of me thinking i'd killed her). I was supplying all the air through that pipe so you may be alright

[splatt]

The only thing that worries me about this is if you forget and drive through a deep puddle!! (you know what I mean)

[siamblue]

umm, whatever came with my old K&N... Think its 60mm. Should the bore matter so much when i'm just moving more cold air to the area?

Andy

It would matter if the area was smaller than the area you were replacing,
Plus the added danger of aqualock,Mind the fords and deep puddles.

[p fandango]

It would matter if the area was smaller than the area you were replacing,

i think he's added it as an additional inlet, not replaced the original 1 out of the airbox

[SaffronC70]

I've cut my aurbox clean in half - nice noise, excuse for a cone filter & dump valve, ECU/MAF seem very happy.

Not so good in traffic though, granted.

Chris

[BagR]

must take some photos to show what i've done!

This pipe is in addition to the one thats already there. I've kept the original feed, and lagged it up with some heat reflecting material. Then i've drilled 1 additional hole in the bottom of the airbox and placed the new pipe just under this hole. Effectively 2 air feeds.

As for the water thing, i'm aware of it . The Filter on my 306 Rallye was at the very bottom of the engine bay, so caution was needed. For this reason i purposefully haven't made a solid connection between the new hose and the airbox. That way, if i do get in a situation where water travels up the new pipe (dear help me if i get in that situation!), it shouldn't just be forced into the aibox.

If all else fails and i don't like it, i have a spare box from a scrappies here

[vt5]

Have you never heard that one of the hottest places to draw air from is close to the road surface? hence why Volvo's standard air feed is higher up on the front of the car.

Also using a bigger bore pipe will decrease the inlet air speed so probably explains why not a great deal of difference is noticed.

Try a larger oval inlet running top to bottom at the side of the intercooler narrowing into an increasingly smaller guage pipe. The venturi effect will speed up the air giving you a faster and more volumetric air intake system.

IMHO though giving a car too much air tends to use more fuel to balance the mixture with little results seen for your efforts.

Trust the engineers at Volvo to have got it right.

Just my opinion.......