I got a question about the VAFC

[94tegRS]

ok, I see you can only adjust the fuel at 8 points on the VTEC lobes and 8 points on the small lobes. well I am guessing it just doesnt have stock fuel at 4995RPM, 5k it adjusts to your settings and 5005RPM its back to stock, but if I had one point set at say 2500 and the other at 3000, is there a dip between 2.5 and 3k? or does it make a smooth curve out of my user defined points.

my friends got a PR3 (B16, right) ecu running a JDM B18C(GSR) and I just was told that the GSRs computer injects more fuel to compensate for the GSR's longer stroke, I figured it pulls this much air and the computer just matches the amount of air with fuel, but I was wrong, so I wanna fix it(I really dont want anything happening to this engine cuz I was the one who did all the labor and if it F's up Ill feel like I did something wrong) but on the APEXi website I also read you cant adjust the fuel more than 12-15% above stock ECU parameters or it thinks boost and throws a CEL and enters limp mode.

is that enough aditional fuel if I were to have VTEC hit at 5k, drop out at 4500 and I can have 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8k points raising fuel for the high cam and 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5k points adding fuel for low cam settings, which takes care of the whole range as long as it makes a smooth curve based on my settings and if the GSR wont need any more than an extra 10-12% to be safe with the CEL deal?

both of which I dont know the answer to.

thanks in advance.

and about the VTEC numbers(just an example, im sure well try a bunch of different engagement points to see where it works the best, and a bunch of disengagement points to keep oit so he doesnt have to downshift as often if hes hossing it)

[Prelude707]

I would just get it dynotuned. No need to play around with all the settings when you'll never get it right without it.

[civickiller]

to get the fuel exactly right, you need to hook it up to a wideband so get an accurate air fuel ratio. and then to find vtec, put it to stock. with no internal mods on the motor, the stock setting is good. not worth the money for dynotuning.

[97CivicX]

the afc does smooth out the fuel curve. and like the others said, you NEED to use a wideband doing what youre doing. butt dyno doesnt work when youre making blind changes to the fuel settings

[94tegRS]

I know I would never get it set right, but leaving it on a B16 ecu running lean would have to be worse than me just blindly throwing in extra fuel over the whole curve? I was telling him about hondata and he might just go that route and have it dyno tuned, but I just wanted to know mainly what I already got the answer to so far and if 12-15% is enough additional fuel for a B18C on a B16 ECU?

[whtteg]

I would think that 12-15% would be too much. I can't imagine that the B18C uses that much extra fuel than the B16A. You could take the car and have them dyno tune it with the VAFC, around here it is around $100 or so to tune a VAFC on the dyno with a wideband.

[94tegRS]

I dont know of many performance shops that have a dyno around here, only actually know of one for sure, garageSPL I think it is. and is there anything new on the VAFC2 or is it just the buttons because the website still shows the pic of the VAFC first version so I figured the specs are also of the first version. and theres on on ebay right now for 100 bucks. 150 buy it now. new ones aree only 220 on ebay though so if it has more features it would be worth it. and thats good that thats too much, I was just worried it would still need enough fuel that the map would show boost since the signal would be too high to the ECU.

Ill talk to him about having it dynotuned. also once they tune it, can you scroll through everything and write down all the settings as a backup in case someone plays with it or somehow you hit the wrong button, turn your car opff and next time you turn it on it initializes a fresh setup and goes back to stokc settings.

[whtteg]

You copuld more than likely have the tuner write the settings down for you incase your battery goes dead or something. I am not really sure about scrolling through the settings as I have never tuned a VAFC before. The tuner should be able to tell you how to do it if he won't write down the settings.

[94tegRS]

alright, thanks, Ill tell him to go get it tuned at garage SPL or somewhere, I figured it would be more than 100 because it seems like all the pulls you have to make to test it out after every correction would just take a long time.

I guess it could be done quickly because Im sure the tech has done alot of them with this same setup, and would just have a good idea of where to start before the first pull.

I cant wait to see how much of a difference it makes.

[superbluecivicsi]

buy this,

http://www.automotiveforums.com/vbul...d.php?t=377315

and you wont ever go back to hacks again.

[94tegRS]

Im not going to a hack anyways, its my friends car, he doesnt have the web though. but I think I talked him into gettibng the VAFC tuned at a shop in the area.
Im confused though, I thought hondata worked with OBD1 and you had to either get the OBD2-1 or 0-1 converison harnesses, but you say it comes with OBD0 injectors and resistor box, and OBD0 IAT

why would you use the older style injectors and box vs the newer style thta dont need the resistor box?

[superbluecivicsi]

Im confused though, I thought hondata worked with OBD1 and you had to either get the OBD2-1 or 0-1 converison harnesses, but you say it comes with OBD0 injectors and resistor box, and OBD0 IAT

the only purpose of the conversion harness is to CONVERT the existing ecu plug to fit the ecu (or vice versa). the iat is for jrsc users, because you have to reroute the IAT back into the JR mani which only fits an obdo iat sensor. the PnH injectors will work on obd1 or 2. the obdo injector harness is pointless, its only purpose is to keep you from chopping up all your original wires into too many pieces. the injector clips are also on the harness. obd0 and obd1 injector clips are the same. i used the PnH injectors in the first place, because, i got them for a steal..........why pass a good deal heres the visual.

the harness in the link in the previous post is easier applyable on an obd0 vehicle. this pix(diagram) above is actually applicable to any vehicle (99-00 civics and 98-01 tegs)that uses a junction plug (located under the intake mani or near the firewall) to route the 12v source to the injectors. the junction plug on older civics and tegs should be located on the driver side shock tower (much easier to mess with when converting to PnH injectors. i believe the differences between the 12v junction plugs between the older and newer civic/tegs is that, the junction plug in the older civics/tegs share the power source with a few other sensors that vary among different models. because they are located on the driverside shock tower, they are more easy to work with. the newer ones dont share it.

anyways,

basically, the diagram above shows that if you used the plug from a prelude (both the male and female parts), you can route your power source from the ecu and the injector wires coming from the injectors to the resistor box. if you ever wanted to revert back to saturated injectors, all you would have to do is............chop off all the wires on the resistor box side and put them all together. now you are easily reverted back to saturated injectors without all the cutting and mess, also still giving you a hassle free option of easily reverting back to PnH injectors if you choose to.

PnH injectors are still being used on saturated applications. many PnH injectors are easily had (ex. DSM injectors). If you can go with saturated injectors in the first place, you should get them. they are more easier and less of a hassle to put them in, but, to many of the custom turbo guys or anyone just looking for cheap good injectors, the 450 DSM injectors can be easily had for $50 compared to RC saturated injectors.

[97CivicX]

safc2 has 12(?) points of correction rather than the 8 the safc1 had. also, it stores the settings in non-volatile memory so even if your battery was unplugged the settings will stay unless you clear them. also, 12-15% would be like running 270cc injectors. almost if not all of the 92-00 hondas came with 240's, so you'd definately be running rich if you tuned it that way

[94tegRS]

is the VAFC2 the same then? 12 points instead of 8?

[whtteg]

Originally Posted by 94tegRS

is the VAFC2 the same then? 12 points instead of 8?

I would assume so if they changed the SAFC2 then I am sure they changed it on the VAFC2.