14 replies to this topic

[The Batman]

right... need to re-address my previous problem, which i thought i solved until bedford track decided to install a new db reader system with a mic on every other corner... It even takes a photo of the offending car

 

anyway... i massively reduced my intake noise by fitting a stab99xl air filter

 

http://itgairfilters...irbox-stab99xl/

 

but i managed to set it off on monday, this could be due to a few variables wind/hoover vxr in front etc but if i can i would rather be able to get on every track.

 

so i am thinking about installying a reducer trumpet before the filter, i have seen a few posts on the mx5 forums that do this when they are turbo'd

 

 

Also i think Nev said about wrapping the air filter box in sound deadening (its currently a alli box) does it have to be something like this:

 

http://www.ebay.co.u...tQAAOxywbJSU~3Z

 

or can i use a foam type stuff like this?

 

http://www.ebay.co.u...pMAAOSwkl5XdJfI

 

Not a fan of the look of the dynomat stuff!!

 

Anyone else got any ideas? or shall i just not do bedford or only when the wind is blowing the opposite way to monday

[Mopeytitan]

I had an apex I on my car when it was SCd and the intake noise (well supercharger noise) was really loud. I fitted the standard na air box and virtually got rid of it altogether to the point I thought the SC wasn't working anymore because I could barely hear it. Probably not a solution for your Exige though but could you not go down the route of a standard air box style?

[jonnyboy]

Yeah oem box.Hondas have no power and torque anyway so losing 5bhp won't do any harm. Paper filter is probably better than most aftermarket stuff too. Another at alternative is not doing track days at Bedford because it's completely shite anyway and they should just hurry up and build houses on it

[The Batman]

I really like Bedford plus it's not far away. I lost 1.5hp going from a open k and n to enclosed one I was thinking about refitting a standard 2.2 airbox / 2.5 v6 airbox but if I can get away with a quick easy solution before I have to start making brackets then I'm welcoming it

[Sticky]

I fitted a Reverie airbox, not sure I have noticed a loss in power but happy to be a bit lower and not get black flagged. I really need to go single exit exhaust too.

[FLD]

Add a resonator box in between the filter and throttle. Loads available on Oems so you could trawl eBay. They are just an empty box so no restrictions if you get the right diameter.

[Johnboyhgt]

That saab one I showed you any good Joe ? Sent from my SM-G903F using Tapatalk

[2-20]

Add a resonator box in between the filter and throttle. Loads available on Oems so you could trawl eBay. They are just an empty box so no restrictions if you get the right diameter.

While not being restrictive, it can seriously modify your engine torque curve...At least on a NA as they are designed to help your air flow at certain RPM by resonnance effect (Helmholtz resonance Chamber)... Don't sure that they reduce intake noise...

Edited by 2-20, 26 July 2017 - 06:52 PM.

[Doctor Ed]

What? That's rubbish. Sorry. Any resonance that occurs in the intake pipe before the throttle body has practically no effect on the harmonic resonant tuning you're erroneously referring to which occurs between the plenum and the valve. A helmholtz resonator in the intake pipe will simply reduced noise, exactly as it's designed to do. Whether a resonator from car A works on car B is a total gamble though. The frequencies are rather specifically tied to the physical characteristics of the intake and engine, so getting one to to work randomly is pretty unlikely

[2-20]

I'm referring notably to the Miata tuning handbook. If you remove the resonator (located before TB) if affect your low end torque.

[2-20]

The Malibu with same engine (L61) is fitted with a resonator

[Doctor Ed]

All good, but I'll Im calling BS on whatever the miata drivers concluded in whatever book that is. Resonance tuning occurs as a consequence of standing wave formation directly at the valve face. Resonance in the intake pipe is simply noise.

[2-20]

Hey !! You are the Doctor ;-))) Not me :-)

[The Batman]

We shall see how my next project does for sound.. if it fits Should be able to reduce/increase noise quite easily depending on if I do Bedford or not.

Edited by The Batman, 31 July 2017 - 09:04 PM.

[Nev]

Best way is R&D one yourself out of aluminium and experiment by spot welding it with various shapes, lengths and baffles etc.

 

After 9 years of mucking about with cars I've come to the conclusion that the only way to make something work the way you want, is to build it yourself. Off the shelf stuff is rarely functional in the way you want IMO.

 

You can use a length of silicone hose (slid up and down) to vary legnths to help with resonance. I was going to do this with inlet manifold runners prior to buying the Klassen intake.

 

GL.

Edited by Nev, 01 August 2017 - 06:22 AM.