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end of the day economy like that means absolutely nothing

anyone can fill a tank, cruise along at minimal revs, make a 70 odd litre tank last for ages and get on here and wank off about economy.

how about the on boost economy. end of the day you got people here with 500 - 800 hp skylines, and your talking about off boost economy? what a joke, we all know they arnt built to be fuel misers. otherwise you wouldnt be running up to 2 bar of compressed air into them.

worry about drivability, starting, that sort of thing. there is going to be little different in on boost economy anyhow.

Nothing wrong with having a daily driver that you able to plod around in traffic, return good fuel economy then hit the track on the weekend and make up for all that plodding around. :P

every ecu is going to aim for the same closed loop settings pretty much.

We can set what load and rev the closed loop drops out, how quick it goes into closed loop and set the afr we want normally set at 14.7 and we can set the clip value so the afr's stay tight at that point.Other factors in the setup but like temp etc but you get the idea.

The days of not caring about fuel use is over with costs so high and we expect minimal compromise even at high power now.

mines tuned with closed loop off with the pfc and i get some shit hot economy on freeway/highway cruising. on street boosty economy isnt too bad, a notch over 400ks to a full tank, which is around 48-52 litres ish.

with 02 feedback off you just dial in whatever afr you like for each cell point and no need for closed loop

my light load low load cells are leaned off the planet and then dialed in slowly towards 12 afr on max load. i didnt adjust max / full load when i turned off 02 feebback, just leaned it out in the 6x6 ish area and progressvily leaned it out a bit more around there, also richened it up near 9x9 as with 02 feedback it was a bit leaner than i had liked.

i found with 02 feedback it would just dial itself back to 14.7 so if it was too lean in one spot, say at 100km it wouldnt matter, but i had to fix those cells once 02 was off

</end rant>

Mines current tuned so that the afr's are @ 14.2:1 during closed loop, out of closed loop until zero vacuum it runs 13:1, on boost it runs 11.8:1.

I'm going to try and run it as lean as I can (being as close to 14:1) up until ~2psi then drop down to 13:1 for up to 5psi then down to 12's from then onwards.

When I say as lean as I can I mean depending on drivability. I don't mind a little doughyness as the 3ltr pulls well and drops out of vacuum so easily.

Unsure how it will affect economy but it should help, I'm currently nudging 470km's per tank if I drive nice, if I decide to give it stick every so often damn it sucks the juice, it easily sucks 70km's out of the tank. :(

I'm sure many of you are aware, theres a german bloke on the rx7 forums who has made a datalogit type box and written software for it.

The software looks pretty damn nice with some excellent features the datalogit is missing. I.e autotune and an improved recal base function to name a couple. :)

Its 'almost' finished, he now has it working with the AP R32 RB20DET pfc so well.. Awesome news for me. :no:

If your keen to have the software working with your pfc head over there (google rx7 forums and head in to the pfc section) dload the latest version hook up your datalogit box, load his program and select scan, then email the file to him.

Thats the thing I don't. :S

every tuner is going to aim for the same closed loop settings pretty much.

The PFC's closed loop is closed loop, being 14.7:1, you cannot make it run leaner even if you wanted to. Tweaking of the inj. map is really all you can do, this attempts to bring afr's closer to the closed loops target afr.

You pick up fuel economy by leaning out the higher load area's, this is where some other ecu's allow you to change where you want closed loop to turn off.

The way I look at it is why run 12:1 up to 2-3psi when it will be happy at 13:1 who knows maybe even 14:1. Sure 14:1 may make it lug a little but who cares when its a 3ltr that has plenty of not too much low speed torque with the skylines gearing.

Tuners generally tune for response and power. Not fuel economy. :D

Tuners generally tune for response and power. Not fuel economy. :(

YES!

exactly, yet we are here arguing over how many extra k's a car gets if we pot around at 1400rpm in 5th on a flat road...

sorry my way of thinking isnt the same as yours, but i think our point is ultimately the same

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