vafc hack on my 00 EX y8 motor
RC 440 and greddy kit
vortec FPR set at 30 psi
stock motor 12 psi
my set up on the fuel was
1-4k was -42
5-6 was -41
6.5 to 7.5 -40
8 to 9 -38 on low narrow throttle i got the cross over percentage on 20%
for wide throttle i just added +1 1 to 4k
and 5 to 6k +2 6.5 to 9k +3
the only time i get check engine is at idle sometimes... it was to lean or to reach
didnt effect the performance at all thoeven with that check engine light on...you can read my post on my car when i first had it and tried it out on a type R on my first day... runs good IMO well worth the time


the lil bog you guys might be talking about is the cause where you put the air temp sensor.... thats what i was told where the hesitation is occuring...if you placed it in the intake arm of the turbo.. thats prolly the problem.. try to get it next to the throttle body like where it usually is but i suggest you put it b4 the BOV cuz knowing all taht pressure might pop that sensor out.. so im guessing putting it right in front of the BOV will keep it from poppin g.. understand what im saying... meaning there will be not as much pressure on that part of the pipping


[Modified by romeo619romeo, 7:54 PM 4/3/2003]

 

Are you talking about the hose that comes from the valve cover and goes to the stock airbox? Isnt it if you put it on the charge pipe before the TB, a "blow-by" occurs? This is what John from inlinepro told me and he connected that hose from the valve cover to the intake pipe of the turbo...?

Other than the crappy partial throttle bucking and unconsistent idle, the hack is ok with me...but def. trading her in next week and trying to run the uberchip as soon as i get my check...
1-8K = -40%

 

no that's the crankcase breather hose thingy... yah... that thing hehe. what they're talking about is the IAT sensor it's a sensor coming out of the same wire loom the MAP sensor plug wires are. it normally goes in the intake elbow as well.

 

at wide throttle I am detonating up in the upper rev range(6500-8400) my AFC is set at -43 from 6000 to 7000 and at 8k it is much richer but still detonating? I am also using a bigger fuel pump with more presure. what can I do? could the ECU be giving it timing in the upper range?

 

What is your boost level? At 8-10 psi you should be right at NA WOT final timing. If 4-6 psi you're 5-10 degrees advanced.

Uhm, how much does the high pressure fuel pump affect your line pressure at the regulator? -43% across, all the way, on a regular Honda would run you lean. Do you have a wideband, or have you checked your plugs?

 

wastegate is set at 8.5psi. I haven't checked the plugs yet but my stock ECU is reading very very rich off it's O2 sensor. also my EGT's are dropping about 15-20degrees at WOT as I roll into boost from a highway roll...... I don't hear the ping though. the exhaust just seems to crackel like almost a early rev limiter, but the RPM's climb very very slowly after about 7k....I am staying out of the throttle till I can get to a dyno or someone can give me an idea to make it run a bit better.

at idle my fuel presure is up about 10psi from stock


[Modified by ITR41, 6:43 AM 4/4/2003]

 

so are you saying it's better to run high boost when using the 'hack'? what's might the timing be at 7psi(that's what i'm planning to boost)? will the apexi ITC helped in the timing issue of the hack?

 

Mine idles like stock despite using 500cc Only very occasionally starting takes a few more cranks. I'm on OBD2 and have no CELs at any point. I think I'm running quite rich tho even with -50% from 1k up to -43% at 9k setup on the VAFC.

ITR41 - What gas are you using? Have you checked your ignition timing?

 

so none of u peeps have the hesitation at 1500rpms???? what would cause your rpms to freeze but at WOT still be able to rev it up this is ****** with my head



[Modified by aemcivic_02917, 4:57 AM 4/4/2003]

 

What sort of hesitation? When u said 'freeze' u mean??

 

http://members.***.net/cjf02917/afchack.AVI

take a look i made a short video to show u guys

 

its like a rev limit at 1500

 

I am currently using the V-AFC hack. It idles pretty good. It is a bit jerky in Parking lots. And it seems to bog out a bit sometimes when i get on it. I have my FPR set at 40psi and my V-afc at -40 all the way across. It seems to idle best at that point. Timing is at -5 of stock. And i am running 8-9psi of boost.
Also, Sometimes when i drive my car for awhile then i stop it and start it back up after 10 minutes my idle will drop all the way down so that it almost dies. I think sometimes it does actually die.

 

Damn guys... -43%... have a tuned afc and at idle im no more then -22.3...440 injectors with forced induction 225 flow in tank fuel pump... afc was tuned at 11 pounds of boost so im a little rich across the board low boost but to me -43% would be entirely too lean... maybe you guys are leaning out too much that's why your hesitating...although that could be a rich problem too but I dont think your running rich a the fuel settings your running...what is your settings while bogging... my afc has been run on a friends civic hitting low 12s for a year... and my car has been running strong for 8 months now...so i know the fuel settings on my afc are pretty damn good...

Chris

 

I use -43% all the way across the board and at WOT my a/f meter shows the last three lights of rich lit up. I'm running really rich at WOT, but other than the buck it drives BEAUTIFULLY. I'm using a walbro 255 lph fuel pump and 450cc dsm injectors. I see all these people running such lower settings than I do but don't see how its possible.

I do get those annoying check engine lights every now and then but nothing to bad to worry about. As for the IAT sensor, I don't even have mine hooked up in the intake track. I do get the bucking at part throttle which is really annoying, and I'm running stock timming, and stock internals. I give the AFC hack an A- from me.
Nick

 

same here... well mine is semi tuned on the dyno... settings range from aslean as -45 and to as high as -40.

 

can it be that the vafc itself is defective? did you try removing the 450cc injectors and going back to stock and see if the problem is still there?

 

d16y8
6.5psi
255lph fuel pump
rc 370cc injectors

i have my setting ranging from -40 at narrow throttle, to -37 at wot. i can't really tell it runs rich or not though

i still get the CEL 13 occationally, it happens almost randomly so when i finally get annoyed at seeing the light, i just reset the ECU and the problem is gone for a while.

my car runs very very nice, it never bogs, and the idle is almost exactly at stock. it's usually at about 700 rpm, but but the car doesn't vibrate one bit, it's great.

however, i do have that "low rpm rev limiter" problem, but it happens for me at 2200 rpms, it's hilarious driving around in a parking lot. anytime else when i give it steady gas it goes right by the 2200 mark, and obvious when i'm WOT my rpm's fly.

so all in all, i'm happy with my v-afc hack, albeit i haven't gotten it tuned yet so i'm hoping my car is ok until i do.

 

isn't it that the vafc hack needs to use 450cc injectors to work properly?

 

No, you get CEL 1 (O2 sensor) and CEL 3 (MAP signal too high).

You're boosting past the abilities of the 370cc injectors and stock Honda fuel maps, which is causing the code 3, and if your O2 sensor isn't switching properly at cruise (bad grounds) or you have your setup tuned to run overly rich all the time (adjust AFC so that you run leaner at lower TPS) then that's where the code 1 comes in.

turb's right, the V-AFC hack and 450cc injectors go hand in hand - anything smaller and you run out of ECU map too soon and anything bigger and the fuel injector control gets muddy and you run like ****. You can probably go 550's, but after that you have to start fiddling the ECU fuel pulsewidth to avoid extreme rich conditions on tip in. Bottom line, 450cc's fall into a "sweet spot" with the AFC hack.

 

From a IM conversation I had with liam821 he told me to set everything to -40% across the board. He said any higher would make the stock fuel map end to soon and can cause a lean condition in the upper rpm range. He was sure @ what setting it start to do this @ though.

My friend is currenly @ -38% with his and no problems car runs good for a Saab T3.

Remember liam821 is the almighty creator of the hack over a year ago.

 

You can go higher than -40%. There is a distinct difference between what the Honda MAP sensor can sense and where that places you in the Honda fuel map. -40% = lean on most setups, run your car on a wideband.

liam may or may not have created it, I don't know, I know more about it than anyone. I've played with Honda fuel and ignition maps in a hex editor, was the only one who knew about the ignition timing situation, and made chips to solve the problem. Most people here think the AFC hack is good up to 11 psi, too, lol

 

no... it's code 13... I get it a lot too. It's the barometric pressure sensor.

 

yeah, no disrespect, but i know how to read the code, it gives Long, short, short, short. the first time it happened i was worried so i checked it for 2 minutes straight, it's 13. i know i only have 370cc injectors so i set my settings to -37 at narrow throttle settings, and -35 at WOT now, it's still running great but hopefully i'll get to a dyno in a week or two.

 

If i were you i'd get some 450's asap. We the the rings on the last block with 390cc's @ 8-9psi. I wouldn't run more than 5-6psi. Also the car felt so much better once we put the 450cc's in.