Right here we go.... The airbox mod makes a difference. Seen the data today at engine dynamics. Should have taken pictures of the graphs but even at stage 1 it helps quite a bit...... And if it's top end power you want, a cone filter, even just a filter fitted to the turbo induction pipe is the best way to get air to the engine and the heat is no issue at all even on the standard intercooler.
yep...on my R26,the ktec induction kit defiantly gives the car more up top. Air is being cooled by the intercooler anyhow...but i am still sure,,when its cold outside..the cars quicker.
Lower intake temp always nets more power, but it seems the stock intake is restrictive on the 225/R26 seeing as the dyno run showed gains with a modified intake. To have the full benefit you would then need to use a cone filter that is completely isolated from the engine compartment heat and have a cold air feed of sufficient capacity to it. Something along these lines: https://en.wikipedia.org/wiki/Cold_air_intake#/media/File:Mustang-v6-roush-intake.jpg (air feed does not need to be routed through the bonnet ofc, it can be routed from wherever you can with the shortest and smoothest possible path) The important thing is to keep all the intake air separate from the heat inside the engine compartment. The heat issue is exaggerated on cars with very little empty space inside the engine bay, such as the mk2 Megane RS. The effect is even more pronounced on cars with fully enclosed engine bays - think all the plastic surrounding the engine in the wheel wells, and the undertray... A simple heat shield to accompany a cone filter (a solution that many tuning companies offer) only helps a little when the whole engine bay is hot from engine heat. The cone filter should sit inside a fully insulated "box" that has no air leaking into it from any other source than the cold air feed pipe, which needs to have close access to ambient outside air. And, for the greatest gains you would also have some heat insulating material on all the air box panels, to lessen the effect of them being heated by the hot air inside the engine compartment. I took a look at the stock air filter part number, and the filter is the same on the 225/R26 as is fitted on the lowest powered diesel mk2 (82 hp). Hence, the total flow area of the filter itself may be the reason for the phenomenon we're seeing here. Traditionally stock intake systems have had huge headroom for tuning, but looking at this Renault air filter, it is in fact quite small for a 225/230 hp engine. So there is likely less headroom than you would typically expect. So then you have the car mapped and airflow goes up by 20% - and you might get to the point where you start to actually lose power due to the flow capacity of the stock filter (remember, this is not the typical scenario). So then you fit a cone filter and ditch the stock air box, and you get improved top end. If you were to combine the benefits of a CAI air box and a sufficiently large cone filter, you might just see some nice improvements. Or you could try an alternative approach and come up with a way to fit a larger factory airbox, one that would fit a larger factory air filter. This might actually be doable if you relocated the battery to the boot. Then you'd have the benefit of factory stock filtration capacity AND more flow capacity...
ITG system draws air in from the wheel arch,and is supposed to offer the best gains... Which should prove the cold air in theory. This subject had been bouncing around this forum from the very beginning! I would still like to see some dyno runs back to back with a stock system, to prove its worth the investment. I think years back,such data was published on here or meganesport.net.
Opening up the restrictove airbox definitely makes a difference, when the car gets a stage 1 upgrade the turbo drains the stock airbox of its air high in the Rev range and gets left with not enough air to feed the turbo. Opening up the airbox means it's always got a big enough entry point to get the air it needs. As far as the cone filter goes, the engine bay gets a good flow of air through it. Most of the hot air flows out through the exhaust tunnel. The bay was designed with flow through it in mind. This is bearing in mind that maximum flow is required. It's not right for my car, the airbox mod however is. If you are running 300+ and doing mainly track driving then a cone filter on the induction pipe will give the biggest gains.
Sorry, but I can’t buy that theory. What you’ve said is that the factory air feed to the airbox is more restrictive than the air filter itself. There really is no way that this could happen in practise. And I’m not convinced that drilling holes in the front of the airbox, or even cutting it open completely will yield any positive effect, the cold air feed to the air box is about the same size as the intake pipe work, so is no more of a restriction pre and post filter. The filter itself is without a doubt the biggest airflow restriction that the turbo has to overcome - modifying the air box does not change this restriction. Interesting topic nonetheless! Sent from my iPhone using Tapatalk
All very interesting, I was surprised engine dynamics had found opening up the airbox made a difference and was the way to go to get a better flow of air. They could of just insisted I bought an induction kit. But after seeing the graphs I will be modifying my airbox. I'm not going to get into a debate about it, I'm no expert for sure which is why I'm taking the experts advice who are drswing on their findings
