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Do I Need Z32 Afm? Hitman Says No!

Drivebai

By Drivebai,
in Engines & Forced Induction

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Cubes Grand Master

Cubes

Posted
Posted

Waz, I don't think its armchair tuning, its the theory and what many others have already been through.

Its quite straight forward. A motor is an airpump its as simple as that. :)

It shall be interesting to see the afr plot once its all tuned up on the std afm.

Be sure to grab one Drivebai.

Don't walk out of there without an afr plot dyno sheet. :)

I would expect it to have a nice afr then dip slightly as it goes a little richer then come back up as it starts using the fuel supplied.

Nothing is wrong with that and it is safe (as safe as the tuner wants it to be) but it does have its limit. 260rwkw may very well be within that limit.

Drivebai Community Regular

Drivebai

Posted
  • Author
Posted (edited)

Why? because even reputable tuners learn something new everyday. I don't expect a tuner to know everything about my car, and he tunes 101 different types of cars so that's why i'm trying to do the most research i can to get the most out of my car.

I trust him with my car, i mean the tune may be awesome with the standard AFM but perhps the tune will be even better with a Z32 AFM.. thats the question i'm asking.. he never said i couldn't put it in.. he just said it wasn't a necessity.

Plus i'm going off other forum members experiences as most seem to say they needed to replace it.

After reading nismoid's post, my car is a daily driver so perhaps the Z32 is better for me.

Yep will try to remember to get the AFR plot for you guys.

Edited by Drivebai
Cubes Grand Master

Cubes

Posted
Posted
Why? because even reputable tuners learn something new everyday. I don't expect a tuner to know everything about my car, and he tunes 101 different types of cars so that's why i'm trying to do the most research i can to get the most out of my car.

I trust him with my car, i mean the tune may be awesome with the standard AFM but perhps the tune will be even better with a Z32 AFM.. thats the question i'm asking.. he never said i couldn't put it in.. he just said it wasn't a necessity.

Plus i'm going off other forum members experiences as most seem to say they needed to replace it.

As I said in different words.. Hitman believes your goals are within the scope of the std afm. Its most likely what he has found from previous experience, you may have an area on the map thats a 1,2 maybe a few kw down compared to what it could be, hitman believes its not worth the added cost or apparent drivability/economy issues you may see should you go the z32.

Myself.. I noticed ZERO difference in economy or driveability going the z32 so I'm not really sure I know what hitman is getting at.

Thats where you have to ask Hitman, its good to know whats going on with your car.

Makes it so much more rewarding knowing the little things. Well for myself at least. :)

Drivebai Community Regular

Drivebai

Posted
  • Author
Posted

Thanks Cubes,

yeah like others have said.. i already got it.. might as well use it.

Learnt heaps of stuff from my last tune with Hitman, he let me sit in the car during the tune and explained what he was doing to the car and how it affects it. Awesome bloke.

chrissso Proficient

chrissso

Posted
Posted (edited)

Hey all, I have a theory.

Alot of cars use MAP sensor and TPS as well RPM to tune the car. (MAFless tune for LS1, ford XR6 Turbo) So why AFM? It's more accurate.

So, you could say that the AFM is good for regular driving. For instance, you are driving to work, or crusing the highway, and the engine would be sucking air at a low eough volume that would be inside the resolution of the MAF. But as soon as you plant it the volume of air going through the MAF is too great for it to calculate, however, you could still get a good calcualtion from the MAP,TPS and RPM, ETC... Can't you tune to do this when the MAF maxes out, you could tune the computer just to use the other sensors?

Just throwing it out there, sounds plausible...

Edited the drunken grammar and vulgarities...

Edited by chrissso
chrissso Proficient

chrissso

Posted
Posted
chrissso,

You'd have to run an ecu that utilizes a map sensor. The r32/r33's don't so once the maf max's out there's no telling how much more air is entering the motor via the use of other sensors.

Are you saying that skylines don't have MAP sensors, or the ECU and even the power fc's, are incableable of tuning from RPM vs MAP? (except for the d-jetro versions.)

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