Is his MAF kit going to include a turbo option or is it just a MAF and you would have to purchase a turbo, injectors elsewhere?

 

I'm pretty sure just the MAF system and not anything like a turbo or injectors, as I believe the whole point of this MAF system (or more importantly, the coding) is to be mapped and tunable enough for any combination of pieces under the hood.

 

PM sent.

 

I'm curious about this...once you've converted to a MAF, why do you need 3D mapping for fuel delivery (forget about spark timing for the moment)? I thought the elegance of the MAF sensor was that, since it directly measures air mass, you can choose an AFR and then simply deliver X volume of fuel (assuming relatively constant fuel density) for Y mass of air? Essentially 1-dimensional mapping. As far as fuel delivery goes, I figured the multidimensional mapping was always an attempt to make up for the inability to go directly from air mass to fuel mass (well volume, technically). Or is the requirement for 3D mapping somehow an artifact of the AFM->MAF conversion on a system that retains the stock engine computer, which was never supposed to handle a MAF?

 

JDS968,
I think you are confusing the "airflow -> fuel" calculation, with the desired "AFR target" calculation.

True MAF understands the MAF sensors, and thus the exact amount of air entering the engine at any given point. The DME then knows the exact amount of fuel to inject to deliver the desired AFR. This is where 3D mapping comes into use. Now we can tell the DME to use different AFRs depending on different parameters. The parameters used for 3D are RPM & Boost pressure. This is unlike the normal 2D systems, which only use RPM to dictate AFR.

Though it isn't quite as big of a deal with an NA car - with a turbo car, which has a much more dynamic range of operation, the ability to dictate different AFRs becomes quite important.

For example. Lets say you are cruising down the highway in a 951 at 3000rpm. Now you floor it. The car will take some time to get to full boost. In a 2D system, where the AFR is dictated only by RPM, you only get one AFR, say 11.5 : 1. Obviously, that is a decent AFR for full boost, but is way too rich for best power/response during the spool-up time.
Conversely, in the same scenario, a 3D system will understand every boost pressure (so all pressures, not just max boost). This system will then dynamically adjust the AFR as boost pressure climbs. So at 0psi of boost it is 13.0:1; at 5psi it is 12.6:1; at 9psi is 12.0:1, ect. (numbers aren't exact - just to illustrate the point)

Hopefully, that made sense...

 

Holy crap! you home or just surfing abroad?

 

Ah, okay. My confusion was that I assumed that with a true MAF setup, you'd be tuning for one target AFR, rather than a variable AFR based on conditions.

 

LOL, the suspense builds....

 

 

What's going on here people?

 

Pm sent

 

Yep, tick tick tick. We have some excited and anxious people waiting for Rogue to release it. In fact my car is sitting hardly being driven now waiting for the release. I am so tired of this old Maf and Arc2 setup.

I really look forward to new technology.

 

Don't need no stinkin' MAF.

 

New techology on the brink of release.

 

You're awfully quiet considering....