Jetex cone filter: my findings after a few logs

Prawn

My other car is a MINI!!!!
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Evening chaps, decided to get a new filter this week, as I found out my CAI currently fited was purchased second hand, so I had no idea how old it was.

after reading other peoples experiences, I called up Bill on Monday morning, and placed an order for a JR Jetex cone filter with an 80mm neck to suit an S3 MAF.

The filter arrived a few days later. I went for the 80mm neck filter despite having an A3 with 70mm MAF to future proof myself incase I go hybrid at a later date. With this in mind, I used a 70-80mm reducer to join the 80mm filter to my 70mm MAF.

So, the old setup:

68382_453931866776_501476776_5834952_3862161_n.jpg


Ebay Cold air induction kit, £40. unknown age.

I did some logs on this setup on Sunday night. 6.5 degrees outside temp, V power fuel. I recorded a peak MAF reading of 171.44 g/s.

I've done LOADS of logs on the car before, and never gotten more than 171 g/s at all regardless of conditions.

So, the filter arrived at work, and I chucked it on in my lunch break:

65121_452768726776_501476776_5808255_1417811_n.jpg


I did a few logs on the way home that evening, sadly I only had Sainsburys 97 RON fuel in her, and the outside temp was 19 degrees. Only did two logs, and recorded a peak of 175.88 g/s.

Result! An instant gain of 4.44 g/s, or roughly 5.5bhp. happy days :laugh:

I noticed yesterday that the filter was flopping around a fair bit where I had it, so I looked at ways of making it more secure. The TIP felt more naturally happy if I pushed the filter towards the engine a tad, so what I did, was Pull the filter outwards slightly on the sleeved reducer it's mounted on. This way, the end of the filter sits firmly against the inner wing, and it's all under slight tension, so nothing moves around at all.

33451_453923321776_501476776_5834676_670889_n.jpg

Very sutble difference, but it makes it much more firm.


Did some more logs this morning at 6am, 11 degrees outside temp, and now half way through a tank of V power.

First 3 logs showed an average of 179.75 g/s! an increase of 8.31 g/s, or 10.4bhp compared to the old filter, then, after cruising along the A3 at 80mph for 5 miles, I did one final pull, 3rd gear from 3k - redline, and it peaked at 183.75 g/s! A whole 12.31 g/s higher than anything I've ever seen before on the old filter. massively happy!

I'm not saying the whole maf / 0.8 thing is 100% accurate, but if the figures are to believed, I started out with around 214bhp, and ended up with 229, a gain of roughly 15bhp. I understand the numbers may be slightly high, but the gains are very real

On the road the car feels move lively, and it definitely much more free higher up in the rev range. Perhaps my old filter was really clogged up? who knows.

Sorry for the mega long post. I'm not suggesting everyone will gain 12 g/s from fitting a jetex filter, but I just thought it was worth writing up my findings. I'm really happy with the results, and so far I've not noticed any of the heatsoak issues people seem afraid of.

For the money, I'm over the moon. I've not had a chance to compare this to a smoothed airbox yet, perhaps I'll throw that in one day and see how it flows. but for now at least, I love the noise this makes!
 
Im thinking of getting one for the colder months,
 
I got mine last week and changed the oil and there seems to be a large difference with the car it seems faster and sounds great!!!
 
interesting Mr Prawn....id love to see what difference this makes on a rolling road in comparison to the standard box, as the sensors dont record the temps of the air going in which could affect the reading some what.....dont you agree?
 
Im thinking of getting one for the colder months,

My thoughts exactly Paul, in my last A3 I used to get really bad issues with hesitation when crossing standing water on the A3 heading to work, so I went back to a smoothed airbox.

On this car I had some serious issues last week in the really bad weather, where it cut out a few times, despite me being ultra careful with puddles and the like. I decided the low down filter wasn't worth the risk any longer.
 
no Tim, you're right in that there are no sensors measuring the temperature of the air before it goes to theturbo, but I've done logs or the inlet temps at the inlet manifold, and despite the increased airflow the inlet temps at the manifold havn't risen at all. I've repeated the logs several times, and I'm getting the same maximum and average inlet temps over repeated runs. Considering I'm running 17 psi through the standard single side mount intercooler, that's peaking at a pretty insanely high 62 degrees. with both the jetex, and the cold air induction.

Another reason to believe the power is genuine, is that timming pull and ignition values havn't changed at all, so it's not sucking in hotter air and pulling the timming back to avoid DET.
 
perhaps, in the interests of a full and fair comparison, I'll throw in my air box (smoothed totally with green cotton panel) one weekend and do some logs with that, to see what's really the best setup :)
 
Glad it worked out well for you dude, I was worried..... lol

Haha, thanks dude :)

I didn't really buy it 'just because you had one' was just the easier way to describe to Bill which I wanted!
i first saw the jetex cones a year ago on a mates LCR, and I've been tempted, but scared off by the heatsoak claims, which I now realise are a non issue!
 
Haha, thanks dude :)

I didn't really buy it 'just because you had one' was just the easier way to describe to Bill which I wanted!
i first saw the jetex cones a year ago on a mates LCR, and I've been tempted, but scared off by the heatsoak claims, which I now realise are a non issue!

Yeah, I know, I was only pulling your leg.

I've always had good results from mine. The only time it seems to be affected by heat soak is in traffic as you'd expect. However, the UBTs soon drop once on the move again. I normally monitor the inlet temps using the multi gauge on VAG COM, and you'd be surprised how much they climb when stationary.

I see you still have the rubber sealing trim along the scuttle panel and the sound deadening on the bonnet. I removed these and it really made a huge difference to the temps under the bonnet. Thats something else to think about....
 
im all for change if it works and can be proven....i've always gone off Essthree's info as you know due to how mucvh time/effort/money he threw at the tests
 
anyone got a link for one of these?

i need another filter to swap out for my carbonio during the crazy winter were bound to have.
 
The Jetex cones do work, and consisterntly show higher flows.
well priced too..

+1, sounds awesome too. Just taken the silencer out of my cat back too and thats added a nice little growl to the exhaust now too.

Nathan
 
Car felt amazing this morning, the jetex filter definitely makes a nicer noise than the old CAI.

I've not run a cold air feed into the bay at all yet. i don't think it's needed in winter, but I'll look into doing it for summer I think
 
Just fitted one of these, not done any logs yet but the sound is ****** great.

I have fitted cold air feed as well, not brilliant as did not have enough. Also dont have any undertray fitted so even cooler under the bonnet!

Will do some logs and post when i have a time....
 
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So you reckon its worth getting the jetex rather than smoothing the oe box with a green cotton panel filter?..also is it worth removing the sound deading under the bonnet etc??.
 
i did a couple of dynos recently where customers wanted a panel filter. I stock green.. dyno showed zero gains. nuff said
larger cones however have shown gains
 
What about remvoing the sound deading under the bonnet etc??..will that lower temp,maybe make it a bit cooler under the bonnet?
 
Nick, your engine bay looks much neater without the old FMIC piping, but why did you remove it?

What have you done with the ignition amplifier? Is it attached to anything cool to remove the heat?
 
New car kev! the old AGU reached 202 000 miles, and was getting a bit rattly inside for a 400 mile a week car, and the call of a facelift car with an ME7 ECU was too great to resist! even with the ko3S the stage 2 AGU was a right handful in the wet, so having ESP on this one is lovely.

So I picked this up a few months ago:

20864_421371236776_501476776_5037329_2849505_n.jpg


New more subtle FMIC comming in the next few weeks, then it's off to Rtech for a stage 2 map.
 
You know what, I didn't even spot that the throttle cable was missing ... I'm so out of touch these days :) So the ESP makes a fair bit of difference? I've never driver a 2WD A3 with ESP, plenty of S3s that had it.

ME7 has so much more potential and scope for future projects.
 
yea, I've found the ESP makes a huge difference, often it's input is minimal, but it's benefit is huge. Like over crests for example, when once the AGU had broken traction it'd take ages to regain it again, but with the ESP, it only flashes on for a fraction of a second to stop the initial spin up, but the benefit of that is carried on for the next hundred yards or so where it's got full traction again.

Rtech now do launch control for the ME7 using 100% standard hardware
 
Me7 is just the standard ecu fitted to loads of vag stuff post 2000. Pre
Facelift a3's will have me3.5 (I think, kev?) where as facelift cars have me7. Me3.5 has no map sensor so calculates duelling based on load and airflow, where's the me7 has a map sensor so boost can be controlled more effectively
 
My racelogic traction control does the same thing by the sounds of it. Factory ESP is nice to have as standard.

Yup, AGU is old skool ME3x. ME7 is quicker, has more inputs to controll fueling, better logging, can be flashed via the diag port, supported buy many tuners etc etc. Older ECUs can be tuned, but it takes more time and less people are interested to try. Easier to go standalone from AGU engines if that's your bag and less emission stuff clogging up the engine bay.

Pros and cons to both, but I'd rather start with a later ECU anyday. Just easier and more future proof.
 
me7 and me7.5 also night and day different..
narrow band on earlier ones, wideband and egt on later ones for example
 
Excellent post.

I've got mine setup like in the first photo, tucked away down the side of the battery with a cold ait feed running from near the fog light.

What difference it would make if the filter was connected directly to the MAF like in the 2nd photo?
 
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The Jetex cones do work, and consisterntly show higher flows.
well priced too..

cheers Bill

speaking from limited knowledge as you know.....

Someone i know very well placed his car on the RR at his work using a carbonio and then no filter..... with no filter at all the car lost 8 bhp according to the rollers, why would this occur and how would this relate to a benefit through the Jetex if it were infact true
 
Bill: Would heat soak not be an issue runing just a cone in Summer (Not that the UK has any hot months nowadays)?


Cone fitted for Winter to gain extra cold air? Baring in mind our night time temp drop to circa 0'C Nov/ Dec / Jan.
 
S3 engine bays are very warm places.. add a shield and cold air duct for vest summer results yes.

As for without filter, the open ended pipe is not ideal for flow.. inlet duct radius helps flow.. which is whats integrated in the filter necks most of the time
 

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