I know I know... Another intake thread. I have search the forums extensively the last couple of days looking at all types of intakes and reading DIY and about 200 threads on the subject.

Ofcourse I have found a lot of people saying it is a waste of money and others who have been very satisfied.

Seeing that Rotary God suggested the Revi Intake I am leaing toward that one above all others. Ofcourse I am also interested in getting the duct with it. Only problem is, it will cost about $440.. which is the cheapest I can find it at the moment.

My main reason of interest is getting better gas mileage. I drive about 100 miles a day for my commute just to work, nevermind driving anywere else. So the optimistic 2mpg increase would be great. I am getting arond 22mpg now. And if I can get that much of an increase in mpg I would save about $280 dollar over the course of next year.

My second reason is I would like a bit more sound from under the hood. I don't want to buy an exhuast cause I don't want to be a rice man... Just the sound of the intake would be good enough for me.

Any other benefits from the intake would be a plus. One problem I didn't forsee is the license plate on the front grill. Would that negate the Revi air duct? Unfortunately Rhode Island requires a front plate.

What I did recently do was buy the K&N drop in Filter, which has made some improvements just not what I was really looking for in the sound aspect as some people reported it doing.

So my question is for the people who were once in my position and pulled the trigger to get the intake was it worth it to you?

Ofcourse I hate beating a dead horse, but this is the question I needed to ask you owners of Revi Intakes and Ram Air Ducts.

when I installed my REVi i couldnt feel a difference.

Sort of a big investment car. You sort of need all the little things for them to add up to appreciable gains.

Not to intake. :)
If you want take the crap out of your stock box:
1. Disconnect and plug the VFAD vacuum line (this will permanently open your secondary intake channel)
2. Remove the panels from the Intake Box. (Installed in there for noise suppression i believe)
That will give you a couple of HP.

If you do some more stuff:
3. Take out your grill and drill 3/8" holes in every cell that is blocked
4. Remove the foam bumper pad and the plastic cover from under the front bumper. (shields the intake from direct air stream)

And you've got yourself a RAM air.

These simple mods will beat the hell out of any after market intake, and will cost you 0.00

You can use the racing beat ram air duct with the oem box. So that's just $140. Then get yourself a nice green air intake filter (it's a drop in replacement for the oem filter) for about $60.

the gains should be similar, though you aren't going to get much of a sound increase.

You can use the racing beat ram air duct with the oem box. So that's just $140. Then get yourself a nice green air intake filter (it's a drop in replacement for the oem filter) for about $60.

the gains should be similar, though you aren't going to get much of a sound increase.

he'll get plenty of sound increase if does the mods I described.

if your method gets sound, then mine would get similar. both require vfad removal, and using the air duct will give a channel for air to head into the intake box.

i never noticed removing the air baffles in the intake box making much of a difference either way.

Could you go in depth a little more when it comes to taking the vfad vacumm line out and taking the panels out.. Im gonna do this today if its easy enough. Thank you.

just browse the DIY forum. I'm sure there's a DIY for VFAD removal... you just have to remove the front bumper, then remove a sock-looking thing that sits over the rebar.

So you remove the whole VFAd or just unplug it?

unplugging it will allow it to suck up air without going through the sock area, but most people remove it completely.

I really don't want to mod the stock box.


I have the K&n drop in filter now. And there was a difference in response and smoother acceleration, just not what I want in sound.

Removing the VFAD completely, will not give you anything performance wise, and will make the car too loud (compare to the stock). It may, (or may not) mess up your idling too. My car idled OK on some days, and real crappy on others, but then I did not have the meshes in either. Eventually I ended up putting the VFAD back in.
Once the vacuum line is off, both of the channels are wide open for the air to come in. Pulling the line off requires just that. just pull it off the metal tube on the VFAD unit, and cap it with a screw or something.
Removing the panels is easy.
Take out the box completely.
Open it
take out filter
look inside the box, and you'll see two parallel plastic panels. They are held in place with a couple of screws. Just unscrew them, and take the panels out.

the mesh is what evens out the air flow for the MAF, that's probably why you were getting a rough idle...

Anyway, I have the K&N ver. 2 intake. I'm going too have too go with the belief that you only see gains on a cold day... On a hot day intakes just seem too breath in the hot air inside the engine compartment, which sometimes (until I had my ECU tuned by RB) caused my engine too die after some consistent high-rpm "spirited" driving

My thought is the Revi intake duct works well with Revi box. I went with the Odula intake duct (which gets cooler air from the front of the vehicle) which is made for the stock box. However, there are threads showing how to get a better fit with the Revi intake duct and stock box.

Did you see any increase in fuel economy when you put the K&N in?

Since you're looking for a fuel economy increase, I'll tell you what I've done. I was getting 22-24 mpg on long trips, interstate driving 70-80 mph. I just installed a K&N panel filter and my last long trip I got over 25.5 mpg. I'll have to see if this keeps up over time, and my old air filter was pretty dirty so that could have been affecting things. But right now I think it does help. If the K&N added 1.5 mpg to mine, I doubt a ram air would add any more, since there is a definite limit to how far you can go. I've already possibly added around 6%, so go figure.

$440.00 for sound? Hell you can get an exhaust for that price. But paying that much for sound is just dumb.

Roto, did you leave the VFAD in but remove the vacuum hose to open both channels?

$440.00 for sound? Hell you can get an exhaust for that price. But paying that much for sound is just dumb.

I know a lot of folks that pay more than that to upgrade stereo systems. IMO the sound of our motor is much nicer to listen too :).

FWIW I have a K&N Ver. II and love the sound. The HKS Hi-power is on order and I'll dyno the combo, base line was done last week and I got just over 170 rwhp.

I have the K&N typhoon type II and it pulled a little harder and gave a LOT a noise.

Not too bad a mod. would the HKS racing suction provide more HP?

As I said before many times. I wouldn't get a K&N unless you have a RB ram or something close, or you will suck up lots of hot air.

RB duct+Typhoon 2 has been good for me. Plenty of added sound if that what your looking for. High rpm on the highway is quite noticeable with added flow from duct.

$440.00 for sound? Hell you can get an exhaust for that price. But paying that much for sound is just dumb.

Roto, did you leave the VFAD in but remove the vacuum hose to open both channels?

Correct. VFAD in ,Vac line disconnected.
Please note i had a bunch of other mods done which I decrivbed earlier in this tread. (drilling the front grill, removing cover and the tyrofoam cusion from unnder the bumper)

Well the story is, I did remove the entire VFAD @ first. And it was kinda loud, but I liked it.
I was running with nitrous kit at the time, and had an intake backfire, which had blown out the meshes, so with no FVAD and no meshes, the idles got screwed up.
then I put the VFAD back in, the car got quieter, but still had a nice angry note in mid to high RPM range, and it fixed my adles.

personally, I wouldn't intake first unless you find a bargain on used parts. Neglecting the noise, you'll be paying about $400 for a part you won't even notice. If you plan to a bunch of mods, I'd save it for later after you've exhausted others with alot more bang for buck. For the same price you could probably get an RP supercat, which will add noise and a proven 8 or 9 at the least, though I don't know how much of that you get with the stock cat-back still installed.

I wouldn't change anything on the car, as far as the intake or exhaust is concerned, because none of the mods add any hp (or very minimal). Just putting in an Intake, and exhaust will run you in the area of $1000. For what? This is a useless and expensive mod.
Modifying the OEM intake will yield you the same (if not more noticeable results) and will cost you nothing.
This is a very well engineered vehicle, everything in it is designed literally with perfection in mind. The only way to get more power out of it NA, is to go with a catless pipe, and then install a stand alone engine management and lean it out. With that you could get 20-30 HP out of it. other than that, you will be throwing your money on shiny parts that cost a lot and improve nothing.

If you leave in the hot climate, drop $150 or whatever bucks on Mazsport cooling kit. It will keep your fans running sooner and faster and keep the engine cooler, thus preventing your car from going numb when it gets hot. You know the numb feel I am talking about? When the PCM pulls back the ignition and dumps fuel into your engine, to cool it off. That is what causes it to become annoyingly unresponsive in the hot days.

I agree with rotorocks. All I did was removed the baffles & silencer horn in my intake box, added a K&N drop in filter and drilled some holes. The change in the intake sound was unbelievable. I've had more people compliment the sound of my car under hard accelration than anything else.

If sound/mpg is what matters get the AEM/Mazdaspeed intake. Has great extra sound and allows the engine to breathe much easier. Plus if you get the Mazdaspeed one it will be covered by warranty.

I considered the AEM/Mazdaspeed CAI, but didn't like how it would just be a pipe sitting there and the filter being so low to the ground in the front of the car.

I like the Revi cause it looks stock, and RotaryGod suggests it is probably the best intake option for the RX-8.

I did order it and it will be coming in on Tuesday. So hopefully sometime next week I can put it in.

Im interested as to how the K&N ver 2 and RB duct setup works and sounds, gains.

Im interested as to how the K&N ver 2 and RB duct setup works and sounds, gains.

The RB duct wont change the sound much if any, but moving just about any speed the RB ram makes the K&N a cold air intake.

I considered the AEM/Mazdaspeed CAI, but didn't like how it would just be a pipe sitting there and the filter being so low to the ground in the front of the car.

I like the Revi cause it looks stock, and RotaryGod suggests it is probably the best intake option for the RX-8.

I did order it and it will be coming in on Tuesday. So hopefully sometime next week I can put it in.

Let us know how it turns out for you, I think I will probably stick with the cheapest route as well and remove any uneccesary parts.

It just makes me so aggrevated that unlike most other cars you cant add small things here and there (intake, exhaust, etc...) to give it noticable gains. Hell it you put an intake on a civic you'd probably get like 30 hp lol.:rolleyes:

I know the 8 is engineered to already be great but I am still unsatisfied with the torque, and the only way to fix it is something I can't afford right now. Is there any other (NOTICABLE) NA ways to increase the hp/torque on the 8 without going FI.

IS there a rouph idle with the mazda speed intake?

Let us know how it turns out for you, I think I will probably stick with the cheapest route as well and remove any uneccesary parts.

It just makes me so aggrevated that unlike most other cars you cant add small things here and there (intake, exhaust, etc...) to give it noticable gains. Hell it you put an intake on a civic you'd probably get like 30 hp lol.:rolleyes:

I know the 8 is engineered to already be great but I am still unsatisfied with the torque, and the only way to fix it is something I can't afford right now. Is there any other (NOTICABLE) NA ways to increase the hp/torque on the 8 without going FI.

Yeah I know what you mean. I got both the intake and the air duct, and will hopefully install them next week.

I know the 8 is engineered to already be great but I am still unsatisfied with the torque, and the only way to fix it is something I can't afford right now. Is there any other (NOTICABLE) NA ways to increase the hp/torque on the 8 without going FI.

Well, I just got the 4.77 rear gear installed yesterday. First impressions are revving faster and somewhat better accleration, although you aren't talking dramatic gains. But it is definitely more fun to drive around town. Should point out that I have a 4AT, so if you have something else, YMMV.

I know the 8 is engineered to already be great but I am still unsatisfied with the torque, and the only way to fix it is something I can't afford right now. Is there any other (NOTICABLE) NA ways to increase the hp/torque on the 8 without going FI.


If you want more torque, getting an intake is the worst thing for your RX-8. I tried an HKS intake for all of 2 days before taking it right back out. The drop in torque was just ridiculous, in stock form the 8 has no problems climbing hills with just mild amounts of throttle, but with the HKS in, I had to completely floor the car and even then it would go absolutely nowhere. Not to mention it was one of the most hideous sounding intakes I have ever heard in any car. :puke:

That is why I purchased the Racing Beat Revi. Not as loud as the HKS, and is almost like the stock box.

Many of us have the RB setup and they are all pleased.

I know I think that the RB setup definately looks the best but does it give you any increases? Are they noticable? Can you hear the intake from inside of the car?

I got the Revi in yesterday along with the Duct.

Now I just gotta find time to put it in :)

After I put it in I will post a report. I know other people have posted reports but some things as to sound and performance gains can sometimes be subjective. I will see i suppose soon enough.

:rock:

Um, performance gains cannot be subjective. You either gain power or you don't. The question is whether you gain any usable power. Intakes in an RX8 cannot be financially viable in any way.

Um the reason I said it is subjective, is the fact on what people feel or perceive after putting in the intake...


I put in the Revi earlier today and drove about 50-60 miles with it... Defeniately feel more power above 5k rpms. I was driving around for about 2 weeks with the drop in filter from K&n... and I feel more top end power over that. Below 5k feels the same as the K&N drop in filter...


The sound is great... Lower tone and a bit louder but not obnoxioulsy louder. The sound is much better than the stock box and drop in filter...

I will post a better in depth report once I do a gas mileage run.

thanks for info guys

NO intake unless it's a turbo or supercharger......

In my opinion it's just a waste of $ and you can't feel the difference.

But, if you insist I'll sell you my KN Typhoon (Version 1) intake for $100 or best offer

I just ordered my AEM today. It really is not much of a money issue since it was a bday present...but I liked how that was actually exposed to the outside airflow with just that one unit unlike buying two different parts to get air from outside the hood. I also think that has the best sound.

Here's what I recommend...drop in a K&N filter...remove the baffles...and remove the entire horn from the inside of the stock airbox, so that you're down to one screen. I have mine this way now and my RX-8 sounds heavenly, just perfect. There's a very noticeable sawing growl now if I apply any more than light throttle, and the sound remains well dampened and smooth without any funny drops or shifts in sound. I have zero problems with idling as well.

I didn't even think of drilling the stock air box, with the current setup now, maybe I should try that next and see what happens...

i noticed a louder intake sound from taking to panels out so if your looking for a good low sound then i would do that.

Most intakes are loud and obnoxious. I've considered 2 intakes that instead of producing a loud noise, compliment the rotary noise of the renesis. Mazdaspeed Intake and Racing Beat Revi intake. If you're looking to purchase an intake I highly recommend the above and would also recommend listening to any of all your purchases on Youtube. :) Gay noob I hate you!

Don't forget the AEM and MazdaSpeed intakes are one and the same.

I ordered the injen intake , lets see what that feels like.

Although I sell that one, too, I think there are a couple threads about it around here somewhere. BHR will, at SOME damned point, discuss airflow, intakes, and why they don't typically do anything for the RX-8. We will publish the relevant info and data about them, which doesn't include rwhp numbers.

I ordered the injen intake , lets see what that feels like.

It's going to suck ass...

I have the K&N typhoon type II and it pulled a little harder and gave a LOT a noise.

Not too bad a mod. would the HKS racing suction provide more HP?

Hey mate, where did you end up getting yours from, and how much?

Cheers.

i noticed someone recommended drilling holes in each cell of the grill that is blocked...does this make a difference at all? also, will unplugging the vacuum line from the VFAD without removing the whole assembly make any significant changes?