lastphaseofthis

The simplest way my brain could solve the problem, and the solution i plan to use.
A. use my scan tool to read the maf of a known good calibration(from any car measuring the same units at the rx8), and having that "control value" datalogged, hook up that MAF up to my modified(4in or whatever) maf housing and have the appropriated screens to straighten airflow, then hooked to use a series of small pc fans to simulate 5 g/s, then a larger fan to push all the way to 600-700 g/s, while observing the Rx-8 sensors voltage. no driving down the road to get a good baseline scale.
b. test at 5g/s... and
10 15 20 25 30 40 50 60 85 100 130 170 215 250 290 350 400 450 500 550 600 650
C. set up timing to retard when the afm scale is out of "good" resolution. ei 215+(which means you'll probably be in boost.
D. test/log/ blow it up.
rinse repeat?

i have notes on the damn thing somewhere with the actual numbers but i think 30-40 is cruise, and anywhere up to 70-80 is where off boost drivability comes from.

MM said just use a cobra MAF btw. then use it's scale.

FazdaRX_8

iTrader: (1)

that does sound like a good test to run through, create a test jig.

I have heard this cobra maf suggestion before, is there a specific year range?
is the scale easy to get a hold of?

TeamRX8

iTrader: (25)

ay, caramba ...

olddragger

iTrader: (3)

if this much air is going to be required would it be better to just convert to a map based system?

zoom44

no.

zoom44

or one of these SCT Performance - More Power! Less Fuel!

wcs

iTrader: (2)

Wouldn't you need a stand alone system for that?

olddragger

iTrader: (3)

maf is a better system, for a street driven car, but mismatching parts is not something I would want to do on this engine especially. Isnt it unk that the pcm can be adjusted to accept a bigger maf/pipe set up? It would make me very nervous at that power level. besides pcms that use a map system also use IAT and baros to compensate just like a maf system does.
Also please dont tell me that the staged oem intake manifold and the small oem TB would also be used on a 450-500 hp 13Bmsp engine either?

lastphaseofthis

And why the hell not. 600, ok, thats pushing it.

a 600Rwhp FD will consume the same amount of air an 850rwhp piston engine.
which means none of those products are good for 600+ on a rotary.
You have to be careful when company rates there product on YOUR estimated hp.

TeamRX8

iTrader: (25)

You only need a 0-5 Volt based MAF and the wiring conversion. It might require a stand alone IAT sensor and wiring conversion if it's not integrated like our sensor or compatible. Then you only need the correct calibration maps for both.

TeamRX8

iTrader: (25)

I already provided a better link that was overlooked

VMP Tuning - Buy Ford SCT & GM Custom Handheld Flash Tuners Performance Economy Towing: VMP 100MM Slot-Style MAF Housing

We already have an 86mm ID, so 90mm is not going to get you much improvement

zoom44

i agree the 100mm mafs are more better for our application

dannobre

iTrader: (3)

I think you will find that 100mm is way too big. You will have a difficult time getting the low end to match up to the scale. If I recall the ECU freaks out if you change the low end voltage value on the table

TeamRX8

iTrader: (25)

I finally found a calibration chart and it doesn't read below 10 g/s so looks like you may be right

I suppose the MAF diameter is less of an issue than the range of the sensor

dannobre

iTrader: (3)

I found one that extends the scale out to about 600g/s and I am going to try it and see if I can get it to work without too much drauma. I think it will allow the lower end of the scale to retain the first cell value and then it should be good. If I can get it to work NA..then it should be better in the upper ranges because it will be in a flatter part of the curve than our MAF...that gets very "vertical" in the stuff up top.

Might be a moot point though if I go to an REW....

TeamRX8

iTrader: (25)

The PMAS HPX-R will work (already checked out the calibration chart), requires a slot-type MAF bung and maybe an external IAT sensor (looked OK to me just roughly going over it)

http://www.massairdirect.com/

EDIT: Looks like the newer HPX-N2 is even better wrt resolution

stinksause

iTrader: (5)

i wouldnt run anything over 3.75 for the OE sensor ... u can calibrate it

FazdaRX_8

iTrader: (1)

Thanks!