Airbox Vs Airbox Without Lid

[MANWHORE]

There is something that has always puzzled me. It seems almost like a double standard.

People on sau always say that it doeisn't matter that the intake piping gets hot, because the air passes throguh it so fast that it doesn't really get a chance to get heated up.

I totally agree that if you stop your car with an open pod, then yes, it will suck hot air in for a split second when you start moving again, but with our turbo cars, all the air under the bonnet will be refreshed in a split second once you start moving again, and it is actually sucking the air.

Once you're moving, all the air will constantly be refreshed, and if it is as sydneykid says that the air moves so quick that it deosn't really have a chance to get hot, then it should be fine.

Food for thought

Edited January 27, 2007 by MANWHORE

[khunjeng]

Post pics of your set up please Khunjeng

not finished yet mate. Started last week and havnt got it done. As in my post is says I'm runnign with a boxed pod setup atm. Hopefully in a week or so my fab. guys will have made it up.

but it will look like the stock units. Just slightly bigger lid and bigger snorkel. They made an r32 one last week that looked good so we copied it and made it a bit bigger.

As for the heating of pipes...I'm one for following the laws of thermodynamics. The transfer of heat is normally from a high temperature object to a lower temperature object. ie. ur hot pipe to the cold air. time is a factor but so are other things like thickness, temp difference etc. Its obvious some some thermal transfer occurs. How much and how much it effects ur output...dont know excactly but it must have an effect.

[Cubes]

Something looks strange how its picked up so much more low end when clearly the stock airbox would not have been a restriction at such airflow levels.

Manwhore... You say the air refreshed... Where do you think the air passes through to get in to the engine bay.

The radiator. The radiator is designed to remove 80-90odd degree heat from the coolant and transfer the heat in to the air.

That heated air is then consumed by the motor.

[Adriano]

. Alot of tuners these days tune on street without a dyno, and just checking everything else n dyno.

Where on earth did you get that idea, usually good tuners only do road tunes if they dont have a 4wd dyno, and are tuning an awd car, thats my experience from the 3 dyno shops ive worked at.

[Adriano]

I would like to see the test repeated more than once to be conclusive, also a comparison of the boost between the two runs, i would be curious to find out why the afr's changed. Also where was the air temp sensor during the runs? I tend to agree with cubes, why did it make more power at low rpm where the airbox would not be a restriction? I would guess the boost was slightly different in the two runs.

[rev210]

I actually ran without the lid at the drags (R33 gtst) a number of years ago to test the lid 'off'. It was 2 mph slower on the terminal speed, slower through each of the traps at 660 and 100ft too. 102mph Vs 104 mph. Obviously sucking down lovely hot air.

The factory snorkel can be improved on like I said earlier. I ended up cutting a duct to the front part and made a cold air feed for it. Does bugger all having said all that.

[QRI05E]

PICS! PICS! PICS! Lets ua have a look at what you got...

[skylinecouple]

Just so happens that I was at Hitmans the other day getting a tune and he pulled the cover off for the last run and got a 2kw increase from mid revs to top end.He reckons a pod would definately be better at a higher output.Bear in mind I have a cold air feed already set up from the old intercooler pipe hole in the guard going to the old air feed under the bonnet.I did this by cutting a hole in the underside of the lid scoop 3" in size.Then ran a heatproof pipe from the old intercooler hole to the new hole under the factory air feed and used a hose clamp both ends.Works great as I know the standard air box can lose 5kws.

[QRI05E]

Yea but the underside of the R33 Air box is "filtered" air section meaning if you put a 3" induction pipe there it will bypass the airfilter...

The only viable method would be to increase the top lid's intake like this:

What you think?

Regards,

Sarkis

[rev210]

Just so happens that I was at Hitmans the other day getting a tune and he pulled the cover off for the last run and got a 2kw increase from mid revs to top end.He reckons a pod would definately be better at a higher output.Bear in mind I have a cold air feed already set up from the old intercooler pipe hole in the guard going to the old air feed under the bonnet.I did this by cutting a hole in the underside of the lid scoop 3" in size.Then ran a heatproof pipe from the old intercooler hole to the new hole under the factory air feed and used a hose clamp both ends.Works great as I know the standard air box can lose 5kws.

Bonnet down or up on that one?

[BAMR33]

My idea is to have a 2.5 inch hole in the side of the airbox and run flexitubing down through the spare intercooler hole and have a pod filter and a shroud around it to guide the air as well as having a panel filter up the top.

I'm also planing to make the air box a larger volume by making the box square at the bottom rather than indented. I going to get it plastic welded and this also moves the postion of the air flow meter and makes it easier to fabricate a stainless intake pipe.

[QRI05E]

Could you please draw up a diagram to illustrate your idea???

Cheers

[gtst25]

One degree increase in intake temps = 10 degrees increase in exhaust temps.

[BAMR33]

I'll have some Engineering student quality diagrams up soon.

[dezz]

What you think?

That is EXACTLY the idea I had...just didn't have it drawn up so neatly...I was gonna have a look at the area tomorrow and see if there'd be anything in the way of making it....

[justin911]

this is wat i did..

from my 'sticking my hand in and feeling the temps' test the air inside the airbox and around the front is cooler than the air inside the snorkel. i use the stock intercooler pipes still so i think they block some of the air like a partition type thing..

also i rekon on the s2's the grill blocks to much airflow, theres no gaps or anything in it.

[QRI05E]

Justin - The problem with your method is that it still sucks hot air in... the CAI snorkel must be 100% sealed and have a direct air feed from outside the engine bay... The R32 airbox can have the easiest CAI setup due to the AFM sucking from the lid leaving the the bottom part in direct acess with the SMIC hole...

Dezz - I have had a look and our idea will work... just need to figure out what materials to use...

Cheers

[dezz]

Justin - The problem with your method is that it still sucks hot air in... the CAI snorkel must be 100% sealed and have a direct air feed from outside the engine bay... The R32 airbox can have the easiest CAI setup due to the AFM sucking from the lid leaving the the bottom part in direct acess with the SMIC hole...

Dezz - I have had a look and our idea will work... just need to figure out what materials to use...

Cheers

The same plastic used for the factory snorkel... Personally i'd want something fabricated by a pro, so it keeps the factory look... Maybe someone like SS inductions (they make a lot of intake stuff for holdens and fords) could make something up

[BAMR33]

Tell me what you people think :sorcerer:

[R31Nismoid]

Just to clarify...

That was open botten with the fan when you did the B&A yer?

If so, did you happen to do a a run with is closed... well... ideally it would be:

3 runs with snorkel, 3 runs without.

That would be interesting