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Hey all, been reading all your views on air filters and induction kits. Ive only got a 105 so i dont expect miracles, i heard that open air kits make the zr lose power? so a closed kit is the way to go i think,

should i go for direct replacement or does anyone know of a good universal fitment, am looking to get some power gains tho. I like the viper but little bit pricey, or is it worth the money?
 

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i have a K n N open filter, to be honest i haven't noticed any performance loss at all in fact i think that it picks up better than before, as for the noise everyone that i know said it sounds awesome. but for this you do sacrifice your petrol consumption now i tend 2 do bout 15 miles less on a full tank which i think is worth it. if u feed the cold air right i dont think performance loss is an issue.
 

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I'd go for the K&N panel filter fits straight into your original airbox mate.

Either that or an Apiro enclosed, about £70 from Banshee and u get a free cold air feed, I reckon it's the exact same as paying £200 for a Viper etc.
 
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Bottom line the way I see it and have proved/disproved on a rolling road.

Open filters will give you a nice induction noise and can improve mid/top power over the standard installation. The racing ZR's use open filters out of interest and not closed induction kits. Why? They are interested in getting the maximum airflow into the engine and at speed, due to the aerodynamic effect of the airflow through the engine and under the car, there is more than enough cool air to remove the heat.

It is at slow speeds or stationary that the problems with heatsoak will occur. Adding cold air feeds will make no difference as the engine will suck the vast majority of air from immediatly arround the filter which will be the hot air that is now not being dispelled. It will not suck air up the pipe (thats what closed systems do). A racing car dosent do much town driving so this heatsoak is not a problem.

So an enclosed system will alleviate this problem by always drawing air from outside the engine bay. This is fine in principle and will give good imporovements if done correctly. A poor installation can actually give a worse result than an open filter. The ZR is notoriously bad for getting a decent cold air feed without major modification. The only easy place available is to the offside of the radiator where there is a large plastic blank. The problem with this is that the air pipe has to be routed across the front of the engine where it will suffer heatsoak freom the exhaust/engine/radiator. There have been various other options, including removing fog lamps and using that, or attaching the intake below the bumper. These are fraught with thier own problems as well.

Again, like the open filter, an intake pipe routed across/near the engine will not matter on the move but will be a problem at slow speeds. The metal/carbon fibre/plastic pipe will heat up and retain heat which will take longer to cool as well, whereas any hot air will just be whisked away.

A poorly made/installed induction kit can also cause air restriction as well if the plenium chamber is too small or the inlet/outlet is too small or kinked.

Ram air pipes are in theory great, but once the maximum requirements for the engine are met, then any excess airflow will just be wasted and stagnate. The other drawback is that as well as air, it will ram bugs, dirt, grit, water and anything else small enough to fit into the intake down there clogging your filter. If it is very low down and you dont have a water trap, then you could run the risk of water ingress if you go through a deep pubble. This WILL wreck your engine, bending con rods/valves etc. If the intake is not exactly into the airflow, but set at an angle then at speed this could act as a venturi which will actually suck air out of the pipe rather than force it in.

The standard setup and the version sold by X-Power relies on an air intake behind the bumper. This dosnt get the minor advantage of ram air, but it does get round the problem of foreign body/water ingress, and venturi effect.

Some of the best results have been had by keeping the standard induction kit and replacing the paper filter with a performace panel filter.

I have had 2 different types of open filters, performance panel filters and am now running an enclosed carbon fibre system.

The first open fiter I had was from Pipercross and bolted directly onto the throttle body. It was LOUD but I lost a huge amount of performance. I then went onot an open Apiro filter which looked great, improved top end power by 2 HP but suffered heatsoak and I used to get poor acceleration and hesitation on pulling away from a standstill. The panel filter I didnt really notice any difference over the original paper filter and this closed carbon fibre kit I have has got rid of the hesitation I had with the open filter. How much power 9if any) it has gained me remains to be proven on a rolling road.
 

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carlszr said:
i tend 2 do bout 15 miles less on a full tank
wow u must have a lead foot! i have a piperx open filter and ive noticed a bit of an decrease in mpg maybe about 40mpg or so but to hear the roar under the bonnet u have to expect some serious petrol drinking. not so bad because i dont do many miles.

also heres a question to everyone, wud u use more fuel doing 70 on a motorway or rallying round back roads?
 

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through experience...tend 2 use more fuel rallying round backroads, doesnt tend to shift that much petrol on the motorway, but i think its down to me revving the life out of it on backroads, good fun though!! :up: :up:
 
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