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Guys,

Ive spoken to a few people and they recommend that I swap over to a D-Jetro for a couple of reasons the main one being throttle response and the cancellation of surge through the afm causing rich/stall conditions. I also just read the new HPI and it seems to confirm all these in a write up.

Does anyone here have any personal experience with them? Just to give you some background my engine specs are:

RB26 Head

Ported

HKS Cams and Gears

RB30 Bottom End

Forged Internals

Garrett T04Z Turbo

9.0:1 Comp Ratio

I aim for this setup to make approx 450awkw on pump.

Thanks for your input

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i would expect better throttle response on the airflow meter setup vs map sensor and the chuffing/shuffling usually occurs on twins that ive seen on the forum. the afm/stalling is usually also caused by incorrect bov setup

Ive spoken to a few people and they recommend that I swap over to a D-Jetro for a couple of reasons the main one being throttle response and the cancellation of surge through the afm causing rich/stall conditions

whoever gave you that advice i wouldnt go back to them for anymore of it :(

Everyone has a different opinion on the Power FC, whether to get AFM's or the D-Jetro version. I bit the bullet yesterday and order the D-Jetro, which has ended up costing me less than a normal PFC and 2 AFM's. I like the idea of MAP's over MAF's because of the stalling and messing with bov's (as said in below posts)

If you'd like to be turned away from the D-Jetro, read this :D

http://www.gtr.co.uk/forum/upload/showthre...?t=39859&page=1

^^but then the second last post gives the D-Jetro some hope, plus all of those guys know what they are talking about :wub:

MAP still works ok but if smooth street manners is your thing then stay with MAF.

I have been in a GTR on D-jetro. Response was awesome and street driveablity perfect.

My own car(S13) I swapped from a rom with Z32 to powerfc D-jetro. The car has never driven better. The responce of low throttle is fantastic. Also if I feather the throttle on and of in high revs(enough the bov goes) the car is not jerky like it was with the AFM.

Saying all this though means nothing, as we all should know by now an ECU is only as good as the tuner tuning it ......

whoever gave you that advice i wouldnt go back to them for anymore of it :D

Choosing a management system, I believe depends on who is going to be tuning your car. You could buy the best management system in the world but if your tuner has no idea about the system there is not much point.

It all comes down to which system your tuner is most experienced and comfortable with.

;) Adam :P

MAP sensor will always be difficult to tune at part throttle on a GTR due to the throttles being downstream of the sensor and so not really reading Manifold pressure. Can the Djetronic correct for throttle position against manifold pressure and react accordingly?

I was referring to the advice of the surging/rich/stalling

Thats not really ECU related and is incorrect information

Wasn't disagreeing with you. I was making an observation and further extending a train of thought.

If NissanFreak is using a certain tuner it is advisable to use the unit he/she recommends/ has the most experience with. (IMPO and others)

R31Nismoid, I'll give you an example.

I heard a reputable tuner say this first hand; he stated "you should not use a PFC with AFM on high mount twins". He gave good reasons why. But we all know there are plenty of GTR's around the world using the PFC unit (with AFM's) with high mount twin set ups.

Personally, I don't believe you can turn around and tell that tuner he is wrong. In his years of experience for a twin high mount set up he recommends a motec or autronic unit using MAP sensor.

*Just an example used has nothing to do with this thread. Just pointing out that differing opinions are not always incorrect*

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