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Morning all!

So besides the standard intake with say a K & N pannel filter, Mania intake and lock stewart ones, are there any custom cold air intakes people have made themselves?

Ive seen a few where they have removed the RHS headlight and put the pod filter there, but as mine is still road registered I dont want to do that. just keen to try something else.
current intake is mania, then i have an NB pipe from AFM to TB.
Oh, will be getting rid of my AFM as now have ECU so any thoughts on different intakes? if you have made a custome one yourself post some pics!

I believe all the good ones involve tapping into the area of cool air and slightly elevated pressure in the HVAC collector box in front of the passenger. I use an original Loch Stewart to do that and it works fine. It does bring a fair bit of induction noise into the cabin. I reckon you could handle that though.

DIY can be pretty cheap and straightforward too. Suggest you wander down to K-Mart or Go-Lo and browse cheap stainless steel vacuum flasks. Some of them give you tapered pipe sections in the right size ranges to link an enclosed pod to a 75mm hole you cut in the firewall.

Matty King wrote one up years ago. http://autospeed.com.au/A_110680/cms/article.html

If you want to retain NB8 cross pipe, then you could fit a pod filter on U bend pipe onto the cross pipe & locate the pod filter behind the passenger side headlight. Then just fit ducted/ vented headlight cover.

Or you can remove the cross pipe & fit pod & custom pipe to throttle body to locate filter behind driver side headlight, & then just fit ducted/ vented headlight cover.

Don't use it any more, so no pic, but I had brake duct piping from a hole cut in the airbox down to & mounted in a hole cut into the plastic tray below the engine.

I've got a mania style intake on mine but with a 'custom' large chambered sponge filter - easily washable and louder induction growl.
its a tube about the size of a medium sized milo container, about 30cm long - a 3" thick sponge filter on the inlet side, and then a spacer 'air gap' then a 2" thick sponge filter then 2" air gap from the exit of the chamber to feed the AFM. (never wise to have a filter right beside an AFM as it makes airflow very unstable to the AFM's sensor resulting with inability to drive on/off throttle [cruising] smoothly - it needs atleast a 2" or greater gap)

My AFM is bored out a smidge (will outline this later)

then through an NA8 ARC chamber to the throttle.

Air temp readings from the grill are typically 4 degrees cooler then the cowling area. Granted my car is black, bonnet is black and this measurement has been done on 30+ Deg c days. On cooler days, the difference between the grill and cowling area is never less then 2 degrees c.

The arc chamber has very much improved low end torque between 1500-2500rpm especially with using airconditioning.
Another nice thing was consistently higher mileage for the same style of driving before the ARC chamber.
I still wasnt able to improve on normal highway mileage of 8L/100 but it did improve city driving mileage driving a similar way.

The airflow temps i measure at the throttle body path are between 10-15 degrees higher then the cowling. (higher in traffic, lower on the highway)

My readings the past week of 800km travelled:
18 deg C Grill
22 dec C cowling inlet airflow
35 deg C throttle airflow

This info is typical of my car's highway mileage the past week.
I dont have any current pics of my car's inlet setup to share right this moment tho.

I have one Works Engineering intake. Filter is enclosed, and comes with a reinforced hose (not the concertina type) with a fluted end.

Please PM me if you are interested.

droo wrote:My readings the past week of 800km travelled:
18 deg C Grill
22 dec C cowling inlet airflow
35 deg C throttle airflow

Curious about this, droo. It sounds like a big rise from the cowl to the throttle. Where do you think it comes from? Headers? Radiator? General engine output? How much heat shielding do you have on the intake system?

Metal ARC chamber?

yep, its an amount of heatsoak on the arc chamber while stationary but as it's extremely thin/light it cools down fast. I have also removed the temp heat shield i made for my headers. I'll re-fit that heat shield and recheck the temps in the coming days. The headers are directly radiating onto the air filter tube which would be heating that 'nicely...'

I'll re-fit the shield tonight, and will follow this up with a comparison of throttle air temps with the stock pipe vs arc as soon as i can.

.. maybe a silly question, but what are the typical gains (bhp/torque) that the NA8s could achieve with just those K&N-style open pod or Mania-style CAI intakes? Are the gains noticeable? I've played around with these in the past with my previous non-turbo rides but seems negligible until I started playing with the intake manifold and exhaust system.

Cheers guys!
Yeah Apu got pics?

I've got the mania set up, sounds great! But now I have the ecu fitted I don't need the afm, so thinking perhaps now I could look at a shorter air intake system but have no ideas haha
Otherwise I'll just get a 70mm pipe made up to replace the afm part

droo wrote:I'll re-fit the shield tonight, and will follow this up with a comparison of throttle air temps with the stock pipe vs arc as soon as i can.

That'd be interesting, droo. I admit I went out and started measuring around the engine bay looking for coldside piping routes when you first posted those temps.

Bryans Integra made 23whp extra with an exhaust and works engineering intake.

Dann

If you want to do something different, why not route it down in front of the drivers side wheel? known high pressure area or use an enclosed filter and attach some ducting out the front bar? you will completely eliminate all the passenger side gear, cleans the engine bay up nicely..

Did this over an afternoon to my daily shitter, clears ok even with the gigantic afm, could have routed in in front of the rad, maybe later. Ive dríven it in the rain with no issues. I have an enclosed filter which I will use later down the track with some ducting it was just a quickie to get the car breathing better with some noise lol

okies, firstly, a messy photoshopped pic of my engine bay tongiht, overlayed with my temp sensor locations and if you have good eyes, a diagram of the internals of my air filter case (done in a rush sorry!)



Secondly, i'm just back from nearly 60km of test driving. : )

re-installed my home made heat shield - and it will stay on : )

now throttle body air temp is reduced A LOT with the arc chamber inlet setup.

There is loads of heat soak into the air filter plastic tube from the headers. (see pic)

Throttle air temps with the arc chamber are now reduced to 11 degrees above ambient, reduced from 17 degrees previously. Can only assume the oem afm-throttle pipe would be similar.

(Front grill temp is my ambient reference, as it's been pretty much consistently what local area weather temps suggest!)

Inlet air temps at the cowling were 3 degrees higher then ambient for today's testing.

Drove 10 minutes around town then 10 minutes at 80kph on the twists in 3rd and 4th gear.
Grill temp 18 deg C
Inlet temp 21 deg C
Throttle Temp 29 deg C
(nearly 25km travelled)

Stopped for 5 minutes.
Heat soak from stopping drove throttle temp to 44 deg C.

Drove again for 10 minutes at 60kph and throttle air temp returned to 29 deg (11 above ambient) in about 5 minutes.


Stopped and changed over to stock NA8 air pipe.
repeated journey in same conditions. Yes, i'm aware that the engine is already hot unlike when i started with the ARC chamber..

Drove for 5 minutes at 60kph, then to 80 on the twisties in both 3rd and 4th gear for another 15minutes (i love my home town area!)
(25km travelled again)

Ambient temp still 19 deg c.
Throttle air temp is 27 deg C.
so at this point the stock na8 piping system is 4 degrees cooler then the arc chamber.

impressive.

I stopped for 5 min to let heatsoak do it's thing.
It went up to the same 44 degrees.

Returned to driving same conditions as earlier, 10 min at 60kph but this time in 5 minutes of travelling, the throttle air temp only dropped to 35 degrees. At 10 minutes of driving it was down to 29 degrees. Not quiet at where it was.

No doubt that the stock tube will get to only 8 deg C above ambient in time (guessing 15 minutes) but around town it's slow to react to fresh inlet air temps compared to the Arc.
(My average trek about town is no longer then 10 minutes for what it's worth)

Im still keeping the Arc chamber installed, and will improve my heat shielding in the mean time, and shield off the chamber too, as well as improvments on low rpm drivability from stationary - ie, air-conditioning on, trying to accelerate without bogging down or revving past 3000rpm. It also provides a longer radiused curve both at the afm side and throttle side, which is in complete contrast to the sharp curves of the stock pipe, and without the internal obstructions on the stock pipes radiator hose allowance.

Overall, the heat shield over the exhaust has made a very big improvement in inlet temps today, and it'll remain on the car and i will make more improvements to it. Next step, I will shield off the gap in the pic above the side water inlet to the block.

I think its safe to summarise from the short trial that it's a given:
Using the arc chamber - Throttle air inlet temps 11 degrees higher then ambient.
Using the stock NA8 pipe - Throttle air inlet temps 8 degrees higher then ambient.

However, the arc chamber takes much less time to dissipate heatsoak when moving , ideal for urban traffic, but in it's current state, doesn't cool the intake air as effectively as the stock setup on sustained highway speeds.

nice job rxmx, and shortened the inlet tract a huge amount too!