Drilled airbox

[p fandango]

in what way can it be made better?, performane panel filter installed into the standard box is just as good if not better than any other set up

from a totally standard system first you've got the snow cap blocking air right from the beginning, the airbox altho good is not as straight flowing as it could be, the corrugated section does nothing more than disturb the air flow, the bends are too harsh etc

as i've said in a previous post, i've ran possibly 5 or 6 (if not more) different types of air filter/intake & despite the scientific info against them my fastest 1/4mile time was with an open cone filter. & when you think that just previous to the run the car was sat in the fire-up lane collecting the heat from the engine bay just shows to me how quickly the cold air gets in so making no difference to heat soak at all

[JelT5]

I have BSR induction kit and sounds amazing!

I'll second that!!!

[T5arrrgghh]

BSR it is then!

[callyuk]

has anyone got a pic of the bsr kit fitted so i can have a look at it

[t5 pete]

Theres one on ebay for sale i have just put a group a filter in myne and i think its brilliant also the only time the filter would really suck in hot air is when its stood also some one on here fitted the bsr kit and found there was no difference between the original and bsr so its really a waste of money the only problem with the standart air box is how it flows theres too many major bends IMHO ide just get a open filter have a look at myne in myne below.
http://cgi.ebay.co.uk/ws/eBayISAPI.d...m=150344744409

[PaulZX]

I drilled my airbox with about 25 x 10mm holes, and it now sounds like I've got a big dump valve fitted.... not a sneezy one, but a whooshy one.... I love it....

[t5 pete]

Heres the bsa type
[IMG][/IMG]

Heres the one ive fitted

[AlanG]

I drilled my airbox with about 25 x 10mm holes, and it now sounds like I've got a big dump valve fitted.... not a sneezy one, but a whooshy one.... I love it....

Still wonderin' why mine was so quiet........Something to do with the K&N?

[t5 pete]

another person i know drilled his air box and didnt get any sound from it he drilled his air box on the cold side i suppose the more holes and the bigger the holes are the more sound you get

[PaulZX]

You can't see any of the holes I drilled without removing the box, and I put a cold air feed to the gap between the battery tray and the air box, to surround the area with cooler air....

People turn round to see me coming when I change gear at normal road speeds from 50 - 100 yds away...

[T5arrrgghh]

You can't see any of the holes I drilled without removing the box, and I put a cold air feed to the gap between the battery tray and the air box, to surround the area with cooler air....

People turn round to see me coming when I change gear at normal road speeds from 50 - 100 yds away...

same size holes in pretty much same places as you say. and being an auto its letting off that gets people looking but i dont have the whoosh i used to have on my old t5 i have the crazy chatter noise!

Alan i have a K&N panel in mine and did in my last T5 so who knows maybe yours is stealth equipped or some such other unexplainable mystery of magnitude!! gonna save pennies for BSR its quite sexual....

[T5arrrgghh]

is this a good setup?

http://www.partsforvolvosonline.com/...oducts_id=5569

[t5 pete]

is this a good setup?

http://www.partsforvolvosonline.com/...oducts_id=5569

Yeah there pretty good i think that set up is the best for closed air filter but once again it has sharp corners and bad bends

[woz]

i find it pretty amusing that people seem to think the standard intake/airbox must be the best "because if its good enough for Volvo to fit it then it must be good", yet seem quite happy to spend money wiping over Volvo's hardwork/expertise when it comes to the engine management. I'll admit its a pretty good system compared to alot of standard intakes i've seen, but think it can easily be better'd

Pedro - I agree entirely - I just don't think hot air holes is the best way to do it FOR PERFORMANCE purposes. Sure if you want a nice noise its excellent.
I have already modded my snow cap (I wondered why it was like that) to hopefully give a ram effect. I now have a air pressure meter and will be rigging up some pitot tubes along the length of the intake tract, and also around the bonnet area to see where the gains can be made - with proof rather than supposition. When done I will sahre the results. Should be interesting.

Should be easy to debunk the "horns relocation" myth. Juries out on the holy airbox theory. The Ram effect of detail design, orientation and location of the external intake (in front of intercooler) will be an interesting exercise!
I have a misfire to fix first then we are on with it.

Also interested in the effect of fitted my Tomcat splitter on uunder bonnet pressures and effect on ducting out hot air from the engine bay.

I apreciate your comments, but I still ain't getting my drill out - I think the gains will come elsewhere.
All the best
Woz

[AlanG]

same size holes in pretty much same places as you say. and being an auto its letting off that gets people looking but i dont have the whoosh i used to have on my old t5 i have the crazy chatter noise!

Alan i have a K&N panel in mine and did in my last T5 so who knows maybe yours is stealth equipped or some such other unexplainable mystery of magnitude!! gonna save pennies for BSR its quite sexual....

Makes no sense mate,was quite disappointed tbh....

[p fandango]

Pedro - I agree entirely - I just don't think hot air holes is the best way to do it FOR PERFORMANCE purposes. Sure if you want a nice noise its excellent.

Hi Woz, noise didn't get me down the 1/4mile quicker

I have already modded my snow cap (I wondered why it was like that) to hopefully give a ram effect.

ram effect is useless once the turbo gets on boost as its sucking in air at a higher rate than atmospheric by then anyway

I now have a air pressure meter and will be rigging up some pitot tubes along the length of the intake tract, and also around the bonnet area to see where the gains can be made - with proof rather than supposition. When done I will sahre the results. Should be interesting.

i'd be very interested in seeing any pressure results from under the bonnet, any chance you can test engine bay pressure both with & without the weatherstrip on the windscreen edge of the bonnet please

Should be easy to debunk the "horns relocation" myth. Juries out on the holy airbox theory. The Ram effect of detail design, orientation and location of the external intake (in front of intercooler) will be an interesting exercise!

the horn relocation mod as i understand it was to meant to lower the intercooler temperatures more than affect air pressure, the more surface area in the air stream the better theory

i've removed the horns, the centre support & most of the front panel. Mainly to save a bit of weight. The idea of clearing the intercooler helped but doubt it will have a noticable effect

I have a misfire to fix first then we are on with it.

mine turned out to be HT leads, couldn't see any cracks/damage just turned out to be a naff set

I apreciate your comments, but I still ain't getting my drill out - I think the gains will come elsewhere.
All the best
Woz

i totally agree & wouldn't drill my own airbox (if i could find it lol) i would just replace it with a cone, my points are trying to disprove the Volvo box is the best design & that open filters (ie cone filters) will lose you power

[850 t5 vs 600cc]

in what way can it be made better?, performane panel filter installed into the standard box is just as good if not better than any other set up

Well i would not go that far. The airfilter is designed with cost, performance, and emmissions laws in mind. It restricts the engine of air therefore using less fuel and making it quieter and better on the MPG and emission gases.
Volvo could of made the car with 400bhp from the factory but it would not of cost £30k new, More like £60k.
Breath in through a sponge then do it through a sieve and tell me whats easier.

[woz]

Hi Woz, noise didn't get me down the 1/4mile quicker


ram effect is useless once the turbo gets on boost as its sucking in air at a higher rate than atmospheric by then anyway


i'd be very interested in seeing any pressure results from under the bonnet, any chance you can test engine bay pressure both with & without the weatherstrip on the windscreen edge of the bonnet please


i totally agree & wouldn't drill my own airbox (if i could find it lol) i would just replace it with a cone, my points are trying to disprove the Volvo box is the best design & that open filters (ie cone filters) will lose you power

Not sure ram effect is totall useless - marginal for sure, but any increase in pressure at the atmospheric end of the pipe will mitigate the pressure loss due to poorly executed tract design. Or rather I will say "should" until I have some quantitave figures to back up the theory. I too have moved my horns, and as I did so realised that the increase in airflow with such a large x-section and low pressure differential will make no difference but looks better. Your mod has at least the nenefit of weight loss. Better flow through the IC will be better achieved by having a better intercooler core (mine has a lot of FOD damage due to no mesh protection on the main intake vent :>(

btw have you read the various articles on http://autospeed.com/cms/A_2162/printArticle.html about air flow? A good read - maybe you posted it up here originally?

I seem to remember you posted a list of bits for your Reverse IC piping - I cannot find it - would you be able to do that for me?

Cheers
W:>)

[p fandango]

Not sure ram effect is totall useless - marginal for sure, but any increase in pressure at the atmospheric end of the pipe will mitigate the pressure loss due to poorly executed tract design. Or rather I will say "should" until I have some quantitave figures to back up the theory. I too have moved my horns, and as I did so realised that the increase in airflow with such a large x-section and low pressure differential will make no difference but looks better. Your mod has at least the nenefit of weight loss. Better flow through the IC will be better achieved by having a better intercooler core (mine has a lot of FOD damage due to no mesh protection on the main intake vent :>(

the looks of the intercooler without the horns in the way has got to be a good enough excuse by itself lol, especially if you've got a mesh grill

btw have you read the various articles on http://autospeed.com/cms/A_2162/printArticle.html about air flow? A good read - maybe you posted it up here originally?

no it wasn't me, thanks i'll have a read tomorrow (i give up easy so hope it doesn't get to technical)

I seem to remember you posted a list of bits for your Reverse IC piping - I cannot find it - would you be able to do that for me?

no problem mate, i'll sort it out tomorrow & PM you (or FFM might have it easier to hand)

[PaulZX]

Here's the full list of bits you need, and a picture of the two pipes assembled.... Also this is presuming you're using the bigger throttle body, if not and you're leaving the standard throttle body on, you need to replace one of the 76mm 90 degree bends, with a 61mm to 76mm 90 degree reducer. The 2.25" pipes are used as couplers on the throttle body pipe.

3" Stainless piping

1 x 80mm
1 x 140mm
1 x 160mm
1 x 305mm

2.25" Steel Pipe

2 x 80mm


Silicone Bits


1 x 76mm to 61mm straight reducer
1 x 76mm to 51mm straight reducer
1 x 76mm to 56mm straight reducer
1 x 56mm to 51mm 90deg reducer
1 x 56mm 45 deg
2 x 76mm 90 deg
2 x 76mm 45 deg

Other bits

11 x 80mm Jubille Clips
7 x 65mm Jubilee Clips

1 x 19mm Air Compressor Fitting