What ECU do you guys have ? Haltech , AEM EMS , Power FC ??? (500hp+)

[GTRPower]

I like the Power FC L Jetro. MAF is the way to go. D Jetro works well too, but I personally think MAF sampling is more accurate than MAP database calculations. Eric Hsu also thinks the Power FC L Jetro works great, prefers using it for street driven cars.

That being said, my silver car has an AEM v1 with MAP. It is what it is, it works, not that thrilled about it, but I'm not buying something else just for the sake of not using a working AEM EMS.

[gtrkrauss]

Im with Jon. For the money you cant beat a PFC. It has all the tuning parameters that you need to make good power. A D-jetro takes longer to tune then the L-jetro since it has to be tuned from scratch. Skyline airflow meters do not really restrict horsepower so you can easily make 500 whp with an L-jetro. If money isnt an option I would be going with a Motec M800 or a haltech ecu. For my Supra build i will be running an M800. The first thing you should be doing is check with your local tuner to see which ecu he is most comfortable with.

[Dragon Humper]

I would favor the Ljetro if Nissan hadn't had their heads up their butts and not included a MAP in their ECU. A pure MAF based system is not very good and makes tuning harder (think guessing and repeating which takes up valuable time) than a pure MAP setup. If it were MAF and MAP together then it would be more accurate than a MAP only system. MAF only has no load referencing and must be extrapolated from the TPS vs MAF tables making cruising and transitions from vacuum to boost a royal pain to tune. It also doesn't deal well with wild fluctuations in throttle input (unless an assload of tuning time is done) and will buck and fart if you are peddling the car to regain traction or to adjust your yaw angle with the gas mid corner.

You wanna have fun, try a factory OBD2 GM PCM, spark and fuel tables are 50x50 with a total of 9 tables to control just the engine, 17 more to control the auto trans.


Jon.

[Skym]

MAP needs IAT (intake temp compensation with hot, cold conditions), barometric compensation (changes in altitude). Some ECU's don't have barometric compensation (need to buy a barometric sensor to have barometric compensation).

MAF uses hotwire and some MAF's have IAT sensor built in next to hotwire. MAF can react to changes in altitude better (more or less air over hotwire) and is faster to tune due to less maps, tables, etc.

TPS is only for transient throttle enrichment (similar to an accelerator pump if have modified carb engines) and is one of the last things you tune (after fuelmap).

Downside to MAF is the location of MAF sensor (stock is a draw through MAF setup) and some ECU's use MAP (intake manifold), MAF (draw through MAF). I think a GM ECU does.

[Dragon Humper]

I've gone from 1444m above sea level to 20m below (it was a "thick" day in Richmond) and only noticed about a .1 to.2 leanout in my AFRs so I don't think its much of an issue without baro compansation. GM uses MAP, MAF, AIT, Coolant Temp and O2 feedback (as do most) for everything other than WOT. There was a time when they only used a MAP (in the dark ages of the '80s) and that made using bolt-ons problematic without a re-tune. Adding a MAF gave you a fudge factor of 15% in airflow before a retune was needed.

Factory Nissan MAFS are very course and aren't really any better at controlling fueling than a pure MAP system with O2 feedback (also very course but less crap to go wrong). My Djetro uses dual MAPs, AIT, coolant temp, TPS and O2 feedback. The inclusion of a MAF would smooth out the fueling a tad if you added things after a tune, like cams or a bigger exhaust, but that's about it. I would take a direct load indicator of a MAP over guessing load from the MAF, TPS and RPM any day.



Jon.

[RB26DEBIGT]

There's so many option . I did a lot of research and i still need to find a good tuner to have feedback about the ecu they used on other car and other setup . I still have my fuel pump to set up , a couple of bushing to change and some work to do on my brake setup . So im not rushing on the ECU for now but all your information is a good point to start with. I still dont know what i really want to do with the car , drag , lapping , daily .... that will change my idea on what ecu and option (sensor) i will buy

[GTRPower]

A vast majority of people I know who run a Power FC L Jetro use Z32 MAF sensors to increase resolution and headroom, and since the L Jetro has a setting for them from the factory it's an easy upgrade.

[Shiven]

Like most of the guys have said, its best to find out what your tuner prefers, as its useless that you buy a top ECU but your tuner cant use it to its full potential.
My tuner strongly recommended Haltech, which is what I went with and its a good ECU in my opinion. Even when he was stuffing me around, i managed to hire a dyno for a couple of hours and tune the car myself, its that simple to use, as long as you have some background info about tuning.

At the end of the day you need to look at what will suit you best, i wanted knock control, boost control, launch control, wideband input and I also like the onboard data logging feature that you can active with a specific parameter. I also wanted to get rid of the MAFs as 2 of them failed, so the Haltech suited me well.