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Hey there,

I'm relatively new to this forum but I've had my '89 1.6 MX for well over a year now. I've finally finished upgrading the exhaust system with a custom 4-2-1 manifold and complete stainless system inc de-cat and it's also running on ULTRA 8mm leads with some fancy NGK platinum plugs.

My next target is the induction system, I have a high flow cone filter but it's attached to the stock piping to the induction manifold and is thus in the standard location, almost wedged up against the washer bottle.

I've seen some of you guys have moved your air filters to just behind the head light and other funky locations to keep the air cool (the manifold is heat wrapped but I'm sure it still gets a wadge of warm air) so I was just wondering if you have any tips to move it to a better location or if there's any kit that will do a better job?

Cheers!
Ed.
 

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any kit that will do a better job?
There most definitely is a kit that will do better than an open cone filter and it's free..... It's the standard air box that a team of AIS designers & engineers spent many thousands of hours and millions of Yen developing.
 

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Discussion Starter · #3 ·
any kit that will do a better job?
There most definitely is a kit that will do better than an open cone filter and it's free..... It's the standard air box that a team of AIS designers & engineers spent many thousands of hours and millions of Yen developing.
[/quote]

Haha point taken! Just have to track a standard box down now!

Cheers!
 

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There most definitely is a kit that will do better than an open cone filter and it's free..... It's the standard air box that a team of AIS designers & engineers spent many thousands of hours and millions of Yen developing.
Worth adding that its development will be to make it remove unwanted NVH, not necessarily to be the best performing.
 

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There most definitely is a kit that will do better than an open cone filter and it's free..... It's the standard air box that a team of AIS designers & engineers spent many thousands of hours and millions of Yen developing.
Worth adding that its development will be to make it remove unwanted NVH, not necessarily to be the best performing.
[/quote]

Granted most AIS design is a compromise of performance, NVH, costing and packaging constrains, but a std air box is still going to perform better than plonking an open cone less that 300mm from an exhaust manifold.

If a little more induction noise is wanted drilling the dirty side of the air box produces some good results for no out lay.
 

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The standard airbox is proven to have several flaws tho, on autospeed he did some pressure differences accross the system and there are some nasty bends and it sucks in warm air.
 

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I never said the standard Mx5 setup was the epitome of induction system design, just better than a cone filter stuck on the MAF in the stock location.

I still think you'd be hard pushed to make a noticeable improvement on the stock setup, OK you may gain 1, 2, maybe 3 hp from moving the filter, ducting cold air etc but is it really worth the cost and effort for a gain that you'd not even notice?
 

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I used some flexible wire wound tubeing which came in a land rover snorkel kit, i re located the cone filter to just under the slam pannel in front of the rad, its a high pressure zone with plenty of cold air, also u can't hear the gay sucky noise which is a bonus too
 

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I never said the standard Mx5 setup was the epitome of induction system design, just better than a cone filter stuck on the MAF in the stock location.

I still think you'd be hard pushed to make a noticeable improvement on the stock setup, OK you may gain 1, 2, maybe 3 hp from moving the filter, ducting cold air etc but is it really worth the cost and effort for a gain that you'd not even notice?
It will lessen the chances of detonation, especially if the ignition timing has been/will be advanced... There have been loads of tests done with aftermarket air filters - remember seeing a test that showed a 13% HP increase with a K&N sealed air filter on a similarly powered saxo VTS IIRC.

That's almost 15HP if my maths is right...
 

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I never said the standard Mx5 setup was the epitome of induction system design, just better than a cone filter stuck on the MAF in the stock location.

I still think you'd be hard pushed to make a noticeable improvement on the stock setup, OK you may gain 1, 2, maybe 3 hp from moving the filter, ducting cold air etc but is it really worth the cost and effort for a gain that you'd not even notice?
It will lessen the chances of detonation, especially if the ignition timing has been/will be advanced... There have been loads of tests done with aftermarket air filters - remember seeing a test that showed a 13% HP increase with a K&N sealed air filter on a similarly powered saxo VTS IIRC.

That's almost 15HP if my maths is right...
[/quote]

The OP initial question was around filter kits and there locations the answer to which is the stock air box is better that an open filter, nothing had been said about timing mods etc.....

And what the relevance of the test on an Citroen Saxo has to do with B6 & BP induction is beyond me. I'd like to see anyone gain a 13% power increrase by nothing more than an air filter on a B6 or BP.
 

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A Citroen saxo VTS is a 1.6 16v, same as a 1.6 mk1 - I'm not saying that they are the same engine, but with similar power outputs, they require the same airflow.. It was purely as an example that more than one or two bhp can be found by fitting a good sealed aftermarket air filter, or to be even more relevant, relocating the air filter to somewhere that it can get colder air.
 

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http://www.mx5nutz.c...r +bonnet +temp
Test 1 - left side/stock
Thermometer 1 @ Rear left = 34* | 58*
Thermometer 2 @ Front left = 28* | 37*

Test 2 - left side/stock (reversed thermometers to ensure they matched up)
Thermometer 1 @ Front left = 30* | 35*
Thermometer 2 @ Rear left = 40* | 44*

Test 3 - left side/TSI
Thermometer 1 @ Front left = 12* | 35*
That's in degree c
Thermometer 2 @ Rear left = 16* | 40*

Big shout out to bicycleshorts for the data
you can get a 1% power increase for every 7 degrees Farenheit and its about 4c to 7f

So roughly 4% increase in power for the drop in temp based on those readings, plus reduction in flow restriction with a better design of pipe work and not including the slight ram effect of cowl or mouth induction, I'd be happy to suggest that's a couple of extra ponies for a bit of faffing, some pipe work and a cheapie filter.

As shown here http://autospeed.com/cms/title_FreeFlowing-a-Miata-MX5/A_110680/article.html

Now that's some theory, maths and real life data from more than one source.
 

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And not only was the autospeed sealed cone set up put on the dyno to show a 5% power gain he also did some acceleration runs. And if you can't be arsed to read it here's the lowdown

Using a stopwatch, and hand-timing some acceleration runs was carried out to compare the new system with the stock one. To avoid the launch variations of a 0-100 km/h run, I chose to start at a cruise at 2000 rpm in 2nd gear, punch the throttle wide open, and run out to 6000 rpm. Redline would have been nice, but I didn't want to break the speed limit by too much... With the standard intake, over 8 runs back and forth I had averaged 6.1 seconds. Fitting the new intake system dropped the average time to 5.8 seconds, a 5% improvement. While the 0.3 second improvement may not seem much, it was highly repeatable.

Can't we just lay this to rest now.
 
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