ill Dyno it first before i change anything =)

When he removed the stock intake, he removed the helmholtz tuned airbox. Only the factory airbox uses this principle. Aftermarkets rely on organ pipe resonance tuning.

Nemesis,

The K&N intake doesn't require the removal of the VFAD system (the part from the picture).

The vac switch and the hoses to the VFAD valve are all still connected once the intake is installed (although it's of questionable utility/benefit since the connection through the ducts is broken by the removal of the stock airbox.



rotarygod,

would construction of a sealed enclosure around a short-ram filter element which connects to the back side of the VFAD assembly restore the Helholtz tuning?, or is the stock airbox itself crucial to the tuning?

form looking at the parts during installation, the stock airbox has a protruding pipe in the backside that's probably pretty similar in lenght from the throttle body to the pipes that come with the K&N and RE short rams.

If you get the intake ducts feeding directly into a sealed box then yes it is still working on a tuned principle. It may not be tuned the same though. The stock box is tuned to account for size and the effect the filter has on the tuning. You may have great results or you may have ok results. It will be tuned different from stock. Try it and let us know.

Yeah, I just figured it out - thanks!

We have tested this kind of setup back in August 2003 before we released the current short arm intake. While we were running the car with the long cold air intake, the car idles funny and also the check engine light comes on after a few full throttle.

Here is the photo of our prototype long arm cold air intake.

http://www.rotaryextreme.com/rx8intake-2.jpg

Chuck Huang

Neat. Are you planning to build a shroud to isolate it further? Is a shroud even necessary?

Good luck on your quest. I was wondering if keeping the stock intake setup (w/VFAD mech) and then extending the longer intake tube with some pipe. What effects would this create?

hmmm i know what you guys mean about the length of the tube, it really affects the IDLE, i dont know why. i think ill just return the old one on for now untill i figure this out, by the way,, in the stock box thers a pipe that pops out to the filter and on each side ther is somekind of a wall seems like its restricting the air??

on this setup where is the MAF located? is there any screens before the MAF?

I've heard most MAF meters need turbulent air across the wire to get a correct reading. if the intakes are streemlineing the flow then you might look at fitting a screen to make it turbulent at that point.

is that so.?

I think I remember a screen being removed during the K&N install ?..

Hey guys a quick idea the mazda6 community was having a large problem with their MAF being way to sensitive and they got in contact with a company called CP-E to create a MAF customizer which helped even out the fule trims and get rid of the CEL they were receiving from the INJEN CAI this company is also making a intake and customizer that will make more then the injen+customizer you can read up on the matter at www.mazda6tech.com if you guys think it would be any help if not then just disregard everything i said lol

Here's a link to the tech post:

http://forum.mazda6tech.com/viewtopic.php?t=509

Basically with a 3 inch intake pipe, and some A/F tuning (along with the maf customizer to nullify any cels from the giant pipe), the CP-E intake on the Mazda 6s toped out at...

200 WHP (no other mods)

With a 25 WHP peak gain over stock in HP, and a 20.0 peak gain in Torque.

The torque curve just goes beserko the gains are so high...its like +20 ft/lbs across the entire rpm band!!!

http://www.mazda6tech.com/images/dyno/cpe6stq.jpg

Our stock AF ratio was reaching 10:1 by redline (actually dips below 10:1!!!!!)...aka super ultra #1 ugly rich. So its a similar (though not really) situation to some of the richness the rx8's been experiencing.

Here's a FAQ on the CP-E unit for the 6.
http://forum.mazda6tech.com/viewtopic.php?t=1009

And here's the contact info for CP-E (I know their looking for an rx8 to possibly work on).

Custom Performance Engineering may be contacted here:
http://www.cp-e.com/contact.php?

Email:
sales@cp-e.com
customerservice@cp-e.com
info@cp-e.com]general information

Phone:
Sales: Josh Adams (410) 703-9365
Tech Support: Anthony Messina (301) 693-7531

Mail:
Custom Performance Engineering
6545 A Mid Cities Ave.,
Beltsville, MD 20705