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I have a dilemma.

I need to pass an SA pits inspection (regency) where they will only pass the car if it has a stock ECU. The car in question is an R32 with a forged RB25, GTR injectors, custom fuel rail, magna flow fuel regulator, gcg highflow turbo and a Wolf 3d that uses a MAP sensor and no AFM.

Now the plan is to just remove the entire intake manifold and swap it with a mates (taking the fuel reg, injectors, fuel rail etc with it), put the stock AFM back and the stock ECU. The car will then be babied to the pits and inspected hopefully pass providing everything else is up to scratch.

Now being as I need a power tune on the fresh motor would I be better off getting a stock RB20 ecu and getting a nistune installed to run all of this gear and just set a low rev limit/air flow cut for when I change the intake/fuelling and then remove it when I put it all back on.

OR should I get the full power tune with the wolf3d (heard they are pretty shit to tune compared to a PFC or a nistune remap) and then swap everything back over and baby it to the pits again?

Cliffs:

rb20 ecu + nistune

pros:

better tune

safer when I drive to the pits and will pass epa etc easily (can have a real lean idle map temporarily)

possibility it will pass inspection without removing parts? (will regency accept a shiny fuel reg rail and injectors?)

cons:

have to swap everything still

more expensive and f**king around as it will need some sensors/loom changed

wolf3d

pros:

only have to pay for tune as I already have all the bits

cons:

worse tune

still have to swap everything but no changing of sensors or loom (apart from afm which is easy)

What do you think guys? Is the tune on a nistune going to be that much better than that of a wolf? The wolf seems to run great apart from a slightly lumpy idle but everyone seems to bash them.

Edited by Rolls
Wolf3D V4 I think.

Your lumpy idle is due to the idle injector pulse width being too short for the injector to open and close properly. There is an easy way around this though. You will currently have your injectors wired as 1+6, 5+3, 2+5, and all injectors are fired once per engine rotation as is the case with batch fire injection. As a result your idle MS pulse width is small.

An RB's firing order is 1,5,3,6,2,4. So to convert your injection to semi sequential you need to rewire your injectors so that injectors 1+5 are on the first channel, 3,6 on the 2nd channel and 2+4 on the third channel. The injectors must be wired in series so that the impedance doesnt overload the injector driver in the ECU, so power one side of the first injector, in series through the 2nd injector and back to the ecu.

Then you change the injector pulse skip setting for banks 1-3 from a skip of 2 to a skip of 5. Then you need to double all the values in your fuel map.

This change will then have the engine idling as smooth as a stock engine because your injectors are not miss-firing.

There is no reason a properly tuned wolf v4 will not run and drive as well as a stock ecu provided the time and effort has been put in to making that drivability perfect. The disadvantage of them comapred to a power FC is that it takes considerably longer to get drivability right. This is to be expected though IMO as the FC comes shipped with all the base maps that are already pretty good, and the wolf is 100% tunable and comes with nothing.

Good luck

Ian

Your lumpy idle is due to the idle injector pulse width being too short for the injector to open and close properly. There is an easy way around this though. You will currently have your injectors wired as 1+6, 5+3, 2+5, and all injectors are fired once per engine rotation as is the case with batch fire injection. As a result your idle MS pulse width is small.

Cheers for this, I will ask my tuner about it and if he can do that. How much worse for economy is batch injector setups vs proper fully sequential from an ECU with 6 injector drivers?

Cheers for this, I will ask my tuner about it and if he can do that. How much worse for economy is batch injector setups vs proper fully sequential from an ECU with 6 injector drivers?

Technically one setup will not be worse for economy or power than the other.

The batch firing is the recomended standard operation that has idle stability issues when large injectors are used.

Semi-sequential (as I call it) where 1,5 are fired, then skip, then 3,6 are fired, then skip, then 2,4 is basicly the same as fully sequential. Technically at idle speeds the trailing cylinders (4,5,6) are going to have a slightly warmer fuel charge but that makes little to no diference at all.

Sequential.... ideal of course. AND if you have a cool ecu like a V500 wolf you can tune individual cylinders and trim each cylinder for optimal burn at idle using a laser heat gun aimed at each exhaust runner.

I am considering using an rb20 ecu with nistune instead now, as I doubt that plus the tune will cost me more than $1k and I should be able to sell the wolf for $500+

The reasoning here is I am not gaining any functionality from the wolf, not to mention it doesn't have 6 injector drivers. I realise that if the time is put into it it will be as good as the stock ecu, but what is the point? Also if I use a remapped stock ecu I then fix the problem of passing regency with an aftermarket ecu. The 20 ecu wont be able to run the VCT but neither can the wolf.

Thoughts?

Also the stock rb20 AFM, will that be good for 250kw? or does it max out below that?

Sorry no idea about the AFM, but the v4 wolf can control the VCT... like all things it requires a little tweeking it get it right but it can do it.

You can run VCT as an on/off under certain conditions straight off an AUX, or if you want to get tricky you can run it off the boost control output.

With tweaking of the pulse width frequencies you can control the cam position at any RPM.

Mines a wolf3d V4 so it would have to run injectors in batch mode, that means you have 2 injectors firing at one time hence wasted fuel etc so I doubt it would pass as easily as a V400. Not to mention I only have about $1800 to spend on getting power tune, passing epa test and getting gtr brakes. If I run out of cash that means my VIC rego will expire and I can't drive the car until I get more cash to finish everything, kind of why Im leaning towards nistune as it will be cheaper and I can then sell the wolf.

V4/V400 makes no diference if you re-wire your batch injection from (1-6,2-5,3-4) to semi sequential 1-5, skip, 3-6, skip, 2-5. The trick is finding someone that understands the injection changes to make it work, and knows how to alter the injector sequencing/pulse skip settings.

But, if nistune is the easier solution you should go with it. If you want to know more about this injection setup thougn ive posted more detailed information about it in the past on SAU. A search should find it pretty easily.

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