21 replies to this topic

[Benzola]

Aye’ Up Folks! I want to do the simple Air Box mod (NA). Just to give me a bit more “grunt” over the Larini (already done). I’ve read every thread on here & I’m still a wee bit lost. What do I drill, where, trumpets etc....

I know many regard this a chav mod (but - as previous - that’s me all over)... I’m no stranger to having a go, but links to pic’s would be great!... If I get leads gaining a result I’ll gladly photograph the whole process & make a “one stop” downloadable PDF guide for others (such as myself) . What say ye?... Might we pool resources?... Cheers. Benzola.

PS: Shed loads done on Lincoln Green past 3 weeks.... Will share photo’s shortly... And MANY thanks to ya’ll for help with everything & making various parts available. The project WILL be complete this side of Xmas. Brilliant!!! Couldn't have hoped to meet a nicer bunch :-)

PPS: Don't want to get too bogged down with the technical on this (I’ve read the threads & know the pitfalls). Just a simple cheap “grunt” that we can do ourselves without wrecking the engine (I know you tubby guys have had grief).

[Bumblebee]

"Just a simple cheap “grunt” that we can do ourselves without wrecking the engine (I know you tubby guys have had grief)" interesting sounds like I've missed something?

[nicollow]

I did this a while back... First step is take the airbox apart and rip the trumpet off the inside. Second, get a decent aftermarket air filter. Third, drill the crap out of the base if you want extra noise. I have just taken off my OEM airbox (including K&N filter). PM me if you want me to buy it off me for a knock down price

[Benzola]

"Just a simple cheap "grunt" that we can do ourselves without wrecking the engine (I know you tubby guys have had grief)" interesting sounds like I've missed something?

Hey Aimy, Google search the entire VX.org site & you'll see what I'm on about. Too many opinions, deviations & speculations to re-quote. Hence my desire to produce a "one-stop-step-by-step" definitive guide (albeit for NA). Benzola :-)

[Benzola]

I did this a while back... First step is take the airbox apart and rip the trumpet off the inside. Second, get a decent aftermarket air filter. Third, drill the crap out of the base if you want extra noise. I have just taken off my OEM airbox (including K&N filter). PM me if you want me to buy it off me for a knock down price

Share the Love... Pic's & specifics for my "idiots guide" (of which I'm one) B :-0

[fezzasus]

Compared to other designs the NA airbox is quite good, you can happy use it with a typical supercharged engine without it becoming a restriction. By modding it, all you will do is increase the chance of introducing water into the box, rotting the filter and reducing the ability for it to flow. I guess that's why you're referring to it as an 'idiots guide'.

[ChrisS1]

I seem to remember reading Winstar did some flow tests with the original trumpets installed and it was more effective with these installed than removed.

[Firthy]

If you want more induction / engine noise take all the sound deadening out behind the rear speakers, that way your air filter will still work properly....... If you want more power my recommendation is don't p*ss about with the induction filter... 2.4 manifold etc...(unless your gonna get it mapped) best mod for me was the tullett 4-1 more torque and a revs out much better.... This is the biggest restriction IMO This has been by far the best mod I have done to my car..... performance wise

Edited by Firthy, 20 November 2012 - 11:55 AM.

[Mangham54]

Or, just to answer your question, simply take a small circle cutter and drill through the bottom section of the air-box as many times as you feel is necessary. If doing so take the trumpets out of the wheel side and bob's your uncle your done. Can't talk about increases in power, but the filter on my NA never got wet (checked regularly), never discoloured any faster than it ought to, other than to show balanced filtration across the paper filter, rather than the 'dark' patch in one spot where the majority of the air flows in the normal setup.

[dw1]

Hi Benzola, I have a spare MMG modded airbox so it saves you all the work (not that there is much work to mod it but I'm a mechanical numpty so I tend to leave things to the professionals). I bought it off Aimy on the forum before I got carried away and went and bought the uber expensive but lovely Dave Harwick airbox costing hundreds. I'm not looking to make any money on it so can sell it at the price I paid for it to cover my costs £40 + £5 postage, which includes the whole airbox and a nearly new filter, in case you're interested. It means you dont have to butcher your original one and can use the MMG one confident you can revert to standard at any time .

[Winstar]

Compared to other designs the NA airbox is quite good, you can happy use it with a typical supercharged engine without it becoming a restriction. By modding it, all you will do is increase the chance of introducing water into the box, rotting the filter and reducing the ability for it to flow. I guess that's why you're referring to it as an 'idiots guide'.

As standard the flow distribution over the filter isn't good but the shape and layout are such to allow it to be easily modified, but it has nothing to do with drilling holes allover the bottom (or fitting an after market element that doesn't filter properly).

To improve the airflow thorugh the filter (which is pretty much the main restriction) follow these simple steps

1 Remover air box from car
2 open the top and dicard the NVH cone and the filter as they cost peanut so you may as well replace it
3 pull the wire reincorced inlet pipe out of the bottom half of the box and cut it in half
4 cut a second inlet hole in the end next to the original one
5 insert the inlet pipes back into the box as little as possible
6 refit to car



First remover the

[Benzola]

Hi Benzola,
I have a spare MMG modded airbox so it saves you all the work (not that there is much work to mod it but I'm a mechanical numpty so I tend to leave things to the professionals). I bought it off Aimy on the forum before I got carried away and went and bought the uber expensive but lovely Dave Harwick airbox costing hundreds.
I'm not looking to make any money on it so can sell it at the price I paid for it to cover my costs £40 + £5 postage, which includes the whole airbox and a nearly new filter, in case you're interested. It means you dont have to butcher your original one and can use the MMG one confident you can revert to standard at any time thumbsup/>.

Could be an option, thank you. I'll give it some thought, but hadn't anticipated any spend on this (other than maybe a new filter, pending condition when existing pulled out). B :-)

[Benzola]

Thanks Winstar... You are a star!... Getting somewhere now :-)

[techieboy]

Hi Benzola,
I have a spare MMG modded airbox so it saves you all the work (not that there is much work to mod it but I'm a mechanical numpty so I tend to leave things to the professionals). I bought it off Aimy on the forum before I got carried away and went and bought the uber expensive but lovely Dave Harwick airbox costing hundreds.
I'm not looking to make any money on it so can sell it at the price I paid for it to cover my costs £40 + £5 postage, which includes the whole airbox and a nearly new filter, in case you're interested. It means you dont have to butcher your original one and can use the MMG one confident you can revert to standard at any time thumbsup/>.

Could be an option, thank you. I'll give it some thought, but hadn't anticipated any spend on this (other than maybe a new filter, pending condition when existing pulled out). B :-)

You'll need all of the VXT airbox mounting bracketry as well, if it is to be an option for you.

[dw1]

Cool, I don't have the bracket as mine is a tubby, so it's prob a non starter then.

[ChrisS1]

The topic is tagged as 'turbo' though.

[Nev]

I don't know what power you are running on your engine, but after recently building my own airbox with 2 panel filters (rather than just 1) and installing 4" pipework to the turbo I got a monsterous amount of extra power (and much more linear power delivery as an added bonus). Anything you can do to increase pipework I/D and breathability/flow of air into and out of the engine will almost always pay dividends IMO. It's been my mantra on my own project and certainly worked, so I think you are doing the right kind of thing.

Edited by Nev, 20 November 2012 - 04:33 PM.

[dw1]

I don't know what power you are running on your engine, but after recently building my own airbox with 2 panel filters (rather than just 1) and installing 4" pipework to the turbo I got a monsterous amount of extra power (and much more linear power delivery as an added bonus).

Anything you can do to increase pipework I/D and breathability/flow of air into and out of the engine will almost always pay dividends IMO. It's been my mantra on my own project and certainly worked, so I think you are doing the right kind of thing.

Good to hear. That's why I'm so excited to see the Dave Hardwick airbox kit go into my car, given MrSimba's and DGs account and dyno tests of it, it sounds like breathability is very important and the added smoothness is a massive plus.

[ade]

This is what I done, finished it off with longer pipes to the side vent

[Ben NA]

Hi Ade, do you get any induction noise from that setup? I'm looking to do the same as I'm getting bored of the standard exhaust note!