Some "bolt-on" findings
 

Ok I am not doing this to start a forum battle just thought I would post my findings. I wanted to know what intake would make a difference. I tested them at the drag strip, at sea level, 62 degrees, FVAD removed, rest of the car stock with the lastest flash and updated starter/plug combo. The DCS was off. Cleared the ECU each time I switched intakes. The car was lanched at 4krpms each time and shifted right at the beep. I took three runs with each and will post the averages for each intake system. Keep in mind I grew up at the local drag track and know how to run it consistantly. I even kept the car in the same lane for each test. First was the factory intake with K&N drop in filter car ran 15.2 @ 94mph. First gen K&N Typhoon system 15.6 @90mph, 2nd gen K&N intake (carbon fiber one)15.9@89, and the last one of night the Racing beat 15.1@95mph. Next time I will test a cat convertor test pipe and let you know.

Nice work....makes me feel better that I bought a high flow drop in filter for $~60...and did not spend $350+ to lose power...still wonder what Mazdaspeed is going to claim for their "Filter on a stick" air intake that they just started selling.

Seems like the stock intake works best unless you need that 1/100th of a second and extra 1 MPH from the REVi.

Interested to know what your stock 1/4mi ET was before any bolt ons.
And what is the midpipe you are going to test? A hi-flow cat or cat-less?

Nice work. I would think quarter mile times or highway 40-80 pulls or some other natural moving timed sequence is the best way for testing intakes. It's not usually practical to dyno test them other than for flow restriction. Having the hood up and a fan angled at your car is not the same as driving.

Seeing as you have access to these intakes, were you going to test them in a highway pull scenario so that air flow is a factor for the entire test?

Also, can you post the second 1/8th times (quarter - 1/8 mile) to see if when the air was moving around the car if any of the performance numbers changed?

Nice job!

I'm kind of intrested as to how the REVi + Ram Air duct functions.

Actually the methodology could be improved, since -even though you claim you have been raised by the drag-strip- the human factor could always mean error in your data ;)

The best and most accurate way to measure/road-dyno a car with certain mods is to find a way to monitor the vital signs of the car before and after, and also perform in some way a rolling dyno measurement.

The only way I can think of, and one that I am trying to implement, is to have a OBD tool (like Hymee's ScanAnalyzer) and a performance meter (like VBox, DriftBox, GTech, AP22). In this way, by doing a simple 2nd gear full RPM pull (from ~1,5K to the fuel cut) and by logging all data from the OBD and the performance meter, you can see if and what effects the various mods had on the vehicle.

I will try to do the same (comparison of stock, K&N drop-in, RB REVi) using the ScanAnalyzer and the GTech, and see what results they produce....

Interesting :cool: k&n really did there work with the OEM intake i mean so much hype on short rams and CAI's and not you just proved that a drop in filter can do more. thats bang for everyones buck :ylsuper:

I wouldn't call this proof. I would call it a strong indication. If all you did with your car is 1/4 mile runs, this might be directly applicable. This is definitely something to keep in mind. If it gets reinforced with additional tests/scenarios/data points, it becomes proof. I don't think K&N would like to find out that their 300$ product is outperformed by their 60$ product.

WELL THIS REALLY SUCKS!!!!!!!!!!
makes me feel like i spent all that money for a loss of power & a cute little sound...

It doesn't prove anything, everyone's engine is different. If you don't do before and after 1/4 mile runs you're probably not going to be able to know if your mod made any difference on your car.

Even with experience, surely it's possible to have inconsistent runs?

It seems to me that if you want to test just the power gains, the ideal thing to do would be to start from a roll, and then floor it once you reach the starting line. That way you eliminate traction issues. The only human skill involved then would be shifting.

you/we did

I think it's a good thing to have the "human" involvement. When we get into our 8s, can we be sure that we are more, just as, or less consistent? He's giving us some VERY good info. Our 8s are on the streets, tracks, and strips. So he's testing the 8 with mods in those environments (in this case, the strip). I like 10krpms idea. It's giving us real world results, not extremely controled environments that most of our 8s would never see.

Yeah, I know everyones engine is different and what not, but this is giving strong indications of what you get when bolting a particular part on.

you are right, it is not fool proof , but it is more real world testing.

Even when i did my review of my HKS "angry mosquito" intake vs the K&N panel filter, the RX-8 felt better throughout the rev range where HkS felt like i loss power and the RX-8 came to life after 7krpm. I have had sevral cars with CAI or WAI intakes as a stage I upgrade, and i can tell you most of my cars beside my turbo cars, all lacked in the lower rpm range, resulting in a slugish or not so resposive take off's.

Now if you equip a exhaust system with a CAI or WAI induction system , the intake becomes more effective. Without a proper exhaust setup , the CAI or WAI creates a bottle neck , too much air in, not fast enough to get the air out, result laggy lower end response. Your car all of a sudden becomes a noise maker. :hahano:

Did you start in the morning, mid-day, afternoon, evening, what?

Sure maybe it was 62 degrees when you STARTED off, but what if this was in the very early morning when the strip first opened? By noon the temp has gone up, by afternoon the temp has gone up even more, then by night the temp could have dropped significantly. You can't tell me that it was constantly 62 degrees the entire day, that's impossible. And ambient temperatures can, and do, play a role in 1/4 mile times.

I can honestly say that I felt my pulley upgrade but when I installed the REVi I didn't feel anything.

I've just ordered my REVI + duct and feel a little dissapointed by this test - however I am hoping that i'll get real gains once the piggyback ECU is tuned to the intake & exhaust .
Have also ordered the AP pulley & Prolite flywheel . If I can't notice a difference with all that on i'll be seriously pissed !

Why does it seem that your trap speed is much higer than it should be for those times. Especially the stock airbox/REVi runs.

i'd wager its because he's launching at 4k rpms which is not the best for lowest et's, but is a point he can launch fairly consistantly at

Ok, makes sense I suppose. Those trap speeds should be accompanying 14.xx second ETs not 15.xx which is why I was confused.

Your on it supergoat - TRAP speed is what's telling the story of power; NOT e/t.

:)

Great test, wonder if you are going to a NA Interceptor setup anytime soon? :)

K&N intake sucks haha, good testing!
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