I HAVE EXPERIENCE WITH BOTH SETUPS, DO YOU????

You have experience with CAPSLOCK too?


S

Holy Great wall of Caps Lock!
Mike: can you REALLY feel the difference in hp and torque?! That's the world's most calibrated butt dyno if you can.
Realistically; it would be almost impossible to notice such a minor differnce in performance.

I would LOVE to see that.

***raises hand*** I've driven cars with K&N, version 1 and Version 2, HKS intake, RB intake, and even AEM intake.
Problem is (as swoope pointed out earlier) it's tough to compare if they're on different cars.
Could I feel a significant difference between those cars: NO. Too close to call as they say...


I was waiting for that.

The difference in feel comes from throttle responce not bhp gained, there's 8% more air going in that the maf can't see ie lean/jumpy on the pedal:uhh:

YEAH ALOT OF EXPERIENCE, CAPSLOCK IS ON AT WORK ALL THE TIME, I JUST TYPE AWAY.

push the caps lock button before posting??? ;) Just messin' with ya Mike.

YEAH, BUT HOW MANY OF THEM HAVE THE RB DUCT W/ THE K&N???? I AGREE WITH THE CARS BEING TO CLOSE TO CALL, BUT FOR ME THE K&N SETUP JUST FELT A BIT MORE RESPONSIVE.

I just saw some mixture data before and after clearing a (+5ish) long term fuel trim. The O2 sensor was saturate rich before clearing the trim and spot on with another NA car once the trim was cleared. The guy also did some steady state driving and we were able to watch the PCM build LTFT. I am working to get the data posted on the https://www.rx8club.com/series-i-major-horsepower-upgrades-93/nitrous-baby-steps-139275/ thread shortly.

I bring this up here because I am wondering if LTFT may actually kill gains from a different intake. For example, let's say your car is around zero LTFT stock and you put an XYZ intake on. The LTFT then goes to +5% and, even though you are getting more air through the engine, the added fuel actually kills power. The difference in the car mentioned above was something like .5 A/F with the extra trim. NaarLeven's car picked up about 8 bhp by making the A/F about .4 leaner.

Maybe one intake arrangement builds trim one way while the other does so in the opposite direction. The one that leans the engine may be giving you more power even if it is not as free flowing as the other.

I may be out to lunch here but you may want to look into the trim deal.

Champ I believe you are correct.

It has been pointed out several times the ECU has a mind of it's own and reprograms the trim levels.

Because several tests have been done on the intakes. Look in RX Tuner, and a poster on here (Polak) did probably the most scientific test on the RB unit, and D-Sport also just did a dyno on the Rb unit. Several other posters on here have dynoed their K&N. The only person "BEING SADLY MISINFORMED" here is you. How much hp do you think you are getting from these units ? How much difference (if any) do you think you are getting from these units ? Again, how much hp do you think your ass or your ears can discern ? Just because one doesn't have a cover, so it makes more noise when you accelerate doesn't mean it works better. If you look at the RB research they are claiming about a 6 hp increase on the top end (supported by the dyno done by D-Sport), do you think your K&N short ram unit is adding 15 hp (again a person's ass isn't going to feel a 5 hp difference) ? At least with an AEM/Mazdaspeed or a RB unit with the ram air attachment they are outside the engine bay &/or enclosed.

You guys have slow cars :yelrotflm :bootyshak

Being new to 8s and an Old Honda guy I understand the all motor, spending way too much money, for a little horspower, disease. Wouldn't money be better spent on the greddy kit or a zex kit rather then CAI, high flow cat/exhaust, power pullys etc. Yea the greddy is pricey and voids warrantys, but the zex kit is cheap and can be removed. I am trying to decide how best to spend money on this new toy of mine and shelling out a chunk of cash on airflow seems as crazy as spending 1200 bucks on a mazdaspeed front end. What should I do? Is it worth putting a drop in K&N filter in the car or should I do a CAI? if so which one is best for the buck.

Some of us want to stay N/A to avoid some of the complexity, hassels and additional cost of a turbo. Sure a turbo adds crazy good hp but some of us are just looking for a little more "pep" from the car. Besides if you wait around and buy stuff used on this forum you can actually get most of the bolt ons for pretty cheap.

If you are looking for simply bang for your buck, a drop in filter would be fine. If you go CAI you can get the K&N II for about $220 shipped on ebay. You could also go drop in filter and Racing Beat air duct. As oyu have stated though you aren't going to get that much out of either set up.

While I too feel like I noticed a *little bit* more throttle response with the K&N and maybe a *little bit* more pull on the high end, I find it interesting that Speedsource uses the factory intake (with some added heat shielding on the exterior) for their race cars. They must not do that by accident.

Possibly the biggest improvement I noticed when going from stock to K&N, to K&N + RB duct, back to stock + duct, and finally back to K&N + duct...was the smoothness of the power band. For whatever reason, the K&N seems to smooth out the power delivery and almost eliminates the dips in power when the different ports are opening.

The added noise is a subjective drawback and takes some getting used to.
Idle seems unchanged stock vs. K&N
Revs do seem to climb a bit faster with the K&N, especially noticeable for me while using heel/toe downshifting.

*I have never measured under hood temps.
*I used the stock air filter with the stock intake.

Please elaborate, I don't understand...:confused:

Why couldn't the accessport improve gains for someone with the K&N to the same extent as someone with the RB? What about stock intake with k&n drop in filter + RB duct?

DUDE AGAIN WHERE ARE YOU GETTING YOUR #'S, WHERE IN MY POST DID I SAY I THINK I GOT ABOUT 15HP OUT OF THIS?????YOU ARE BEING SADLY MISINFORMED YOU NEED TO GO BACK AND READ THE HOLE THREAD AND TELL ME WHERE I SAID I GOT 15HP???? AND THE RX8 IN THE DSPORT MAG HAD MORE MODS THAN JUST THE REVI INTAKE. WHY DO YOU HATE THE K&N SO MUCH IT DIDNT DO ANYTHING TO YOU, HAVE YOU TRIED BOTH SETUPS???? AND IF YOU RESEARCH AND READ RACING BEATS SITE YOU'LL FIND THIS.YOU NEED TO START READING THINGS TWICE SO YOU'LL UNDERSTAND BETTER.

From Racing Beat, "If you are interested in obtaining maximum horsepower at the extreme upper end of the RX-8 power band (i.e. racing or high performance applications), but are willing to sacrifice some level of drivability, we can make a recommendation for an alternate product from another manufacturer."
http://racingbeat.com/FRmazda4.htm (under the Revi FAQ)

TEST IT OUT BEFORE YOU START BASHING ON THE K&N SETUP I HAVE. OTHER WISE YOU SHOULDNT EVEN SPEAK ABOUT IT.

Intakes do not EVER make more power on the RX-8.
What they do, through crafty manipulation of the MAF, is produce leaner A/Fs in the RPMs above 5500.
Effectively, they move the HP peak down, which allows for claims like "adds 15 HP" because, if you are at the same HP at 6800 RPM that you would be at 7200 RPM without the intake, you have gained 15 HP at 6800 RPM.

Its a shell game.

Sorry but you are clueless. Don't know how else to say it, that the other 10 posters here haven't said it the way you want to hear it.

By their statement on their website, and several dynos done that RB Intake puts out about +6 hp at the top end, about 7-8 with the Ram Air attachment. Understand ?

The human body (ala your ass dyno) can not detect the difference of a few hp more or less. Understand ?

So whether the K&N is putting out 0 hp or +10 hp, your body wouldn't be able to tell the difference between that & a RB unit that you claim there is a difference. Understand ?

The AEM which is outside of the hot engine bay has dynoed about 8 hp. The K&N is a short ram intake unit, inside the engine bay, so very doubtful it is even making that hp number. Understand ?

Going back to you body not being able to tell the difference between a few hp, the only way you could really feel the difference between the 2 units is if the K&N unit made 15-20 hp (big enough difference that your body could feel it & we all know it doesn't). Understand ? That's the EXAMPLE used that unless it made SUBSTANTIALLY more hp than the RB unit, your body/ass can't tell the difference.

The D Sport article had several items, but they broke down the hp gain from each unit. Ala adding the exhaust added +3 hp, after adding the intake, it added this MORE hp, etc. Get it ?

You might have some kind've hard on for your K&N unit, but what people here have been trying to tell you is that ass dynoes are notriously inaccurate, and several dynoes have shown that there is literally no difference between hp gain between the 2 units. Understand ?

Before you pull the BS about have I tried it. Yes I have. My car has the Rb unit, and I have driven & ridden in cars that have the K&N unit, the HKS unit, & the AEM unit. Difference is very little. Noise does not equal hp gain.

Unbelievable. Try actually looking up some info. on here before opening your mouth. YOU CAN"T FEEL 1-2 HP.

Exactly - The horsepower of your car will vary more during the day (due to changing temps) than you'll gain from the K&N.

Does the moving of the torque peak mean less bhp top end?
I can see why people feel a difference as the power comes on over a shorter rev band. ie butt dyno feels change like a turbo coming on boost(not as much;) )

I am all for a little more pep with out complexity. A turbo loks great on paper but all the stuff that goes with it will probably keep me from doing it. I would like to AutoCross or Solo1 my car soon so I will probably only do a few slight mods that keep me in the B stock class.

An intake will put you out of the B stock class.

WHERE DID I SAY" ACORDING TO MY ASS I CAN FEEL ABOUT 2 OR 3 HP GAIN " WHERE IN MY POST DID I SAY THIS??? WTF ARE YOU TALKING BOUT, AND WHERE DID I SAY NOISE EQUALS UP TO HP DUDE????? YOU'D HAVE A BETTER IDEA IF YOU TESTED IT ON 1 CAR, NOT JUST RIDDEN IN OTHER PEOPLES CAR, I BET HE DIDNT EVEN HAVE THE RB DUCT WITH IT.

NEXT TRY TO LISTEN MORE TO WHAT YOU READ, AND STOP TRYING TO PUT SHIT IN MY MOUTH ABOUT THINGS I DIDNT EVEN SAY.

Let's calm down or this thread will be closed.

Mike, please try and turn off the CAPSLOCKS.

Thank you.