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GTR - MAP or MAF better?


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Will be looking at fitting an after market ECU in the near future to my GTR.

I've heard that the 6 throttle body setup of the GTR makes it difficult to tune with a MAP sensor.

Thoughts or recommendations?

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Gav,

It all depends on the amount of power you want out of the car. MAP sensors are better for high horsepower, but will give you reduced resolution for your A/F mixture. MAF's are good if you have Z32's but even they will run out of resolution on a high horsepower engine.

I run a MAP, but that's because I didn't want the restriction to the airflow, but you can still get 900hp cars running on MAF's. If your buying engine managment then get one that has the option of MAP sensor, but allows for the use of other MAF's.

The six throttle bodies make it more difficult to tune whether you have MAP or MAF, but this is only really a problem on high horsepower cars, which will often use a large single throttle body, not something I'd worry about until you hit 400rwhp.

See'ya:burnout:

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Thanks for the comments

Probably belongs in another thread, but the reason I was asking is that I am considering using one of the new Wolf 3D P&P ECUs for my GTR.

From the specs that I have read, this can only use the internal MAP sensor that comes with the unit. The Wolf, however, seems like pretty good value and should have all the functionality that I need.

I am very familiar with the PFC from my previous S15 and got some good gains by fitting an RB25 AFM on the SR20 motor.

I would have no problems with using a PFC and 2 x Z32 AFMs on the GTR, however I really would like air intake temp. correction for Perth's hot summer days!

By the time you get the PFC, Commander, 2 x AFMs and Data-Logit (if you want to log runs/ load alternative maps) you are just about into Motec territory for cost!

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Hi Gav,

I am in Perth and have the Wolf 3D Ver4 P'n'P in my car, I run the map sensor but am sure that you can leave the factory AFM in if you want, don't know if it supports the Z32's though. You can still have the temperature compensation even without the AFM.

I heard from Steve at SST, who fitted my Wolf, that the new P'n'P for the GTR may contain 4WD control functionality, do you know if this is true?

Good luck with making a decision, it's not an easy one to make.

See'ya:burnout:

P.S. I am very happy with my Wolf.

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Almost certainly will get Steve to do the Wolf install for me.

Glad to hear that you are happy with the work you had done.

Can't imagine how the ECU would control 4WD functionality as it would need to interact with the ATESSA computer. Still, will let you know what is possible when I get this done in a few weeks.

Cheers

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