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Posting this up on behalf of a mate of mine who's also on here, and will no doubt stick in his 2 cents :miner:

Apparently no-one beleives him that you can instantly gain 5kw+ on the dyno by just removing the airbox lid.

I was getting a touch up on my tune this week and after it was finished and dynoed, I got another run done with the airbox lid taken off.

Nothing else was touched. These runs were literally back to back, same dyno, same day, same tune. Only difference was the airbox lid was removed for the second run.

scan0002-1.jpg

As you can see, with no airbox lid (the blue line) there is a clear gap over the entire graph. More power everywhere, with even more top end.

It also affected the afr's as you can see, and was knocking a bit at the top end. A re-tune would be needed if you were to run with the lid off all the time.

So as you can see, it DOES increase power....happy Justin? :laugh:

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Not starting an arguement. . . . . Just food for thought!

What hasn't been considered here is real life conditions. In that test the results are conclusive but it was carried out on a dyno with (what i suspect) was an open bonnet and massive fan creating air flow.

But if you carried out the test in normal road conditions (closed bonnet with out readily avalible cold air in stop, start or even spirited driving) you could assume the same rule applies as for pods = heat soak and sucking in trapped very hot under bonnet air.

this arguement will never be resolved if even the japanese tuners run both factory airbox's and non-enclosed pods in their high powered cars even to this day.

Personally, which ever you chose, they both require sealed cold air feeds. Which one you chose depends on your own preference

my car has neva run an enclosed pod and has run magical at calder running good times and even on street. Suffers in heat though. Alot of tuners these days tune on street without a dyno, and just checking everything else n dyno.

I totally agree Matt, an open bonnet will not allow the opened air filter to hear soak thats why i will be customising the top lid on my car's air box to act as an CAI yet able to clear the FMIC kit once fitted...

However, nice result :cheers:

Cheers

my car has neva run an enclosed pod and has run magical at calder running good times and even on street. Suffers in heat though. Alot of tuners these days tune on street without a dyno, and just checking everything else n dyno.

I know of several people that run non-enclosed pods and haven't ever had a problem but I know my car (an R32 which I have retained the standard airbox with a fabricated intake to the factory spot and now a second feed via the spare intercooler piping hole) runs consistant intake temps and flows just as well but with no chance of defect and reduced noise.

vacuum tests through the intake system have shown the only real restriction was the feed to the air box. So fix that and your laughing. (on an R32 GTS-T with only light mods at this stage)

R33 and R34 with their diferent air box setup may find totally different results, I wouldn't know.

At different power levels the field moves again and the induction bellows has even been known to suck closed. So I wasn't giving a difinitive statement saying exposed pods are bad just that any intake is always going to benifit from a DECENT cold air feed.

As I said, it's your choice but would it be fair to say that if your car goes magically with an exposed pod that it might possibly go magically+1 with a sealed partition and cold air feed?

I think tuning on the road is better than dyno tuning (but thats a whole other subject).

I was pionting out the fact that you don't drive around with your bonnet up and a huge fan to supply an abundance of cold air to the panel therefore you can't relate it to a street applicatiopn were the panels only form of cold air feed would come from ram air only when the car is adiquately moving.

Out of interest where was the air temp sensor when you did the two runs? Just interested as I did the same thing but both runs were the same - for both my runs the air temp sensor was on the flat panel filter. Cheers.

I have had my old r32 turned and as stated earlier we cracked the airbox but on mine it made no differance .The reason we cracked it was to test the cai .Was done on the dyno with cool air fan blowing to the front of the car all dyno runs were done with the bonnet down to simulate actual driving conditions cai ran from airbox to front bumper air intake worked a charm test was done by Hitman who reconed that it might have even lost a little if anything .Goes the show the importance of proper engine breathing and a good cai.

Cheers Peter

put the bonnet down and that power goes south for the winter. You can modify the top front of the lid for another more forward facing duct. As long as there is a duct collecting cool air outside the engine bay it's all roses.

Always do the final tunes with the bonnet down it gets you a better base for your road tunes.

What you have proved is that the stock box is not supplying enough air.

stock GTST box is restrcitive above about 230rwkw. But ur results show its restrictive everywhere. Intake pipe will collapse as the stock instake wont allow enough air in above 230 I found. GTRs dont have this issue as they feed air from both the snorkel and the wheel arch which is enough to fix the problem.

If you want to run a stock box with power levels above 1bar then u need to vent the box better. I have designed a new lid and snorkel setupto keep it stock looking which should do the trick.

Currently I had to revert to a Pod setup which I have boxed and covered with Heat Foam stuff. Plus I have a 3" duct from the front bar where the stock IC pipes were.

When running on the dyno with the stock box...I took the lid off and tried which helped...but not a viable solution for driving under normal consitions so whats the point.

Essentially u have proved that the filter element is not the cause of most concern,,,its how the air is getting into the box...the reason pods work is they free up that restriction...but have the neg. effect of potentially sucking in hot air which probably defeats the purpose. Duct it from the fron, box it up and u will be fine.

However due to the two intake mod rule in Vic...I want to retain the stock air box and hence designed a new one that looks stock.

I removed the airbox lid on my car. (cut it all away except for the outer rim that holds filter on)

Then I mounted it vertically behind the headlight.

Then ran a duct from front bar up behind headlight.

Never suffered in heat, always wanted to suck cool air. Pretty easy to do.

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