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Hey all,

I was just dreaming a little this afternoon, anyone know what kind of a pigyback computer I could use on an fj?

or suggestions or whatever? I looked at the powerfc but the fj wasn't in the list of stuff it would do, or is that just a list of ones you can plug it into and have drive away settings?

thankyou!

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I think Mines did a modified ECU for DR30's .

Sounds hard but if you could adapt the CAS to an early SR20 signal you may be able to use the SR loom and ecu to run the engine then substitute an Apexi PFC . The early Red Top SR20DET I think still used a distributor so its optical disc may fit . With PFC's you can generally change to higher flowing MAF's , Skyline PFC's can use the Nissan Q45 V8 AFM so it's worth a look .

Cheers A .

Edited by discopotato03

With the Power FC you can just chose the airflow meter you are running from a list and it will automatically run it.

They is a HKS F-CON pro on FJ20.COM that may be for sale. Its in canada but.

Edited by sr201600

From what I have seen in the DR's that come up for auction on yahoo Japan, they have a tendecy to run GTI-R looms with the power FC as Gtir still run a dizzy. But if you are going to go to that much effort you might as well go a full aftermarket comp, microtech or haltech or something.

Edited by DR JOSH

Mass can be calculated given MAP, air temp, and cylinder capacity. Sure, it is calculated, but that is where your tuner earns his / her money.

I have just (as in yesterday) put a Megasquirt on my NA FJ20 in my DR30 RS. I used the factory wiring for everything but the TPS and MAT sensor. I wanted to use the factory wiring so that I could unplug the Megasquirt and plug in the factory ECU (with the re-install of the MAF and original throttle switch). It is literally a 5 minute switch over job.

Once I put a diff back in the car, basic tuning will begin. Fine tuning will be done on the rolling road, so while I am there I will plug the original ECU back in. Needless to say, the results should be interesting!

I have a plan to slap a turbo on the side of the NA block at Xmas, so having an ECU that would cater for all possibilities was important. Cost was also important. All up, the Megasquirt cost me about $450, including sensors.

Fair enough , most use MAP load sensed management .

The factory chose Vane type or Hot Wire sensors for their accuracy . The vane type was made under licence from Bosch and was use to measure the mass of the airflow , the temp sensor should be in the AFM unit . The Hot Wire AFM is the most accurate and needs no temperature compensation because its part of the signal it generates . Load sensing from MAP runs into problems with pressure pulses . If atmospheric pressure is reached before full load (NA) all you have is the rpm signal to tune with . Running throttle bodys shows this up all the time and TPS (even more crude) or MAF is the only answer .

The aftermarket manufacturers seem reluctant to go to MAF technology which is a pity because there are definate advantages . There is no lack of quite high capacity MAF sensors , the GTR brigade often use two like Nissan did .

Cheers A .

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