just finished hooking up my turbo with the VAFC hack...got a question
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just finished hooking up my turbo with the VAFC hack...got a question
so far i haven't experience the hard starting that some got and i haven't test drive the car yet coz it started raining already and timing was advance. there's one problem though and i don't know if it's because of the hack.
the car started fine and during warm-up it idled smoothly but after it reach operating temperature the exhaust is making a wierd noise and each noise the engine jerks.
it's hard to describe the sound but it's not a very successive sound like bop-bop-bop-bop but it's more like bop/pop-(1 second interval)-bop/pop-(1 second interval)-bop and engine jerks each time it bop/pop.
here are my vafc settings, pls note that these are only base setting since i haven't test drive the car:
throttle point - lo=98% hi=99%
wide throttle ----- narrow throttle
lvt ----------------------hvt
1k - -37 --------------- 4.5k - -35
2k - -37 --------------- 5k - -35
3k - -37 --------------- 5.5k - -35
4k - -36 --------------- 6k - -35
4.5k - -35 ------------ 6.5k - -34
5k - -35 -------------- 7k - -34
5.5k - -35 ------------ 8k - -34
6k - -35 ------------- 9k - -34
the very first setting was 1 - 3k = -40 but that wierd sound came up and then i tried -35 it sort of smooth out a bit but came back again so i just put it in -37 for now.
any thought on why it's making the wierd sound?
by the way, the car is a 99 SiR and the timing was advanced(i'll have it retard) but i don't think the advance is causing the stupid sound. the engine is still good since it was overhauled and i observed the 1000km break-in period.
any help will be appreciated.
the car started fine and during warm-up it idled smoothly but after it reach operating temperature the exhaust is making a wierd noise and each noise the engine jerks.
it's hard to describe the sound but it's not a very successive sound like bop-bop-bop-bop but it's more like bop/pop-(1 second interval)-bop/pop-(1 second interval)-bop and engine jerks each time it bop/pop.
here are my vafc settings, pls note that these are only base setting since i haven't test drive the car:
throttle point - lo=98% hi=99%
wide throttle ----- narrow throttle
lvt ----------------------hvt
1k - -37 --------------- 4.5k - -35
2k - -37 --------------- 5k - -35
3k - -37 --------------- 5.5k - -35
4k - -36 --------------- 6k - -35
4.5k - -35 ------------ 6.5k - -34
5k - -35 -------------- 7k - -34
5.5k - -35 ------------ 8k - -34
6k - -35 ------------- 9k - -34
the very first setting was 1 - 3k = -40 but that wierd sound came up and then i tried -35 it sort of smooth out a bit but came back again so i just put it in -37 for now.
any thought on why it's making the wierd sound?
by the way, the car is a 99 SiR and the timing was advanced(i'll have it retard) but i don't think the advance is causing the stupid sound. the engine is still good since it was overhauled and i observed the 1000km break-in period.
any help will be appreciated.
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From: OCONUS
Re: just finished hooking up my turbo with the VAFC hack...got a question (_Endless_)
i get the same thing and i think that its because its pretty rich on idle. i have mine leaned out at -48 and i have tried between different settings and still the same thing
i have just learned to live with it
i have just learned to live with it
Joined: Mar 2002
Posts: 265
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From: socal. 626
Re: just finished hooking up my turbo with the VAFC hack...got a question (dirtySOHC's)
hope this helps...
Originally Posted by dirtySOHC's
Im sure you all know about the honda-tech afc hack....poor mans hondata. Where you control boost using an afc with a MAP sensor hooked up to the TPS on the apex...i found a better one.
When i rebuilt my last engine i didnt want to use the secondary injectors (f-max erl mf2 fuel system although i had 550cc secondary injectors not 440cc) anymore and wanted something better. I read about the afc hack and thought i would give it a shot. I have a dsm so finding dsm injectors were easy.
My first impressions once i had it all working is...well it worked! I got the boost up to 9psi and it seemed to work pretty good, at least at WOT. EGT and a/f gauge both showed good numberes, and i was also monitoring the o2 voltage by using the "blue wire mod" on the afc which was also good.
The problems started happening while at 1/2 throttle. I drove my honda to oregon from san diego last week and going up and down through the mountains really sucked. I kept having to change the damn cross over point from vacuum into boost on the afc to match the current altitude so the car wouldnt run lean. But even with the right cross over point the car would start going into boost and the honda computer would change the air/fuel from rich (cuz of the afc) so a leaner value. (thats what close loop mode is all about right?) I could watch the EGT increase as this happened. There was also a stumble as the honda computer fixed this. It was pissing me off to no end.
So for a few hundred miles i was playing with the afc trying to make it better...and i just couldnt get it right. So then the thought came.
The afc hack you use a MAP limiter, and then step up from a negative value for fuel with the afc (i was stepping up to around +5%) once the car starts to boost.
So i was thinking, isnt a limited MAP (with a missing link check valve whatever) and the afc stepped all the way to +5% the same as an unlimited map with the same boost? (that is if i got the damn thing tuned right)
So i pulled into a gas station and modded the fuel system. I removed the missing link so i had an unlimited map. I set my AFC at -40% from 1000rpms to 8000rpms so it would keep it no matter what boost level i was running.
I started the car....and it works. It works really well. Its night and day difference. Its AMAZING. In and out of boost you cant tell the difference from a driving stand point. Transition into boost...well there is no transition..its not there because its that smooth. Its as smooth as my eclipse. 1/2 throttle into boost is the same way. 1st gear burnouts feathering the gas so you dont slam the rev limiter...smooth as silk as if you didnt have a turbo. Its a poor mans hondata only i think its just as good.
EGT, a/f, and o2 voltage are all good also.
I have a friend with a b16a/turbo in a 95 civic coupe running 7-9psi. He was running the afc hack like i was. He drove my car...almost drove it off the road because of the torque steer (hah gotta love the d-series axles) but was really impressed by how smooth it was. We rewired his AFC back to stock removed his check valve set his afc at -40% across the board and took it for a spin. The first words out of his mouth were "wow..what a difference that made..its smooth." His over rich in boost, ugly transitions, and all the other bad side effects were gone. Hes using a p28 chipped ecu with a dohc mugen program.
So this is my currect setup:
d16y7 block with z6 head (hey it was cheap) z6 head gasket
p28 ecu (stock unchipped)
99 Turbo DSM 450CC injectors
89 CRX Si resistor box
Apex AFC fuel computer
Walbro 255 lr/hr high flow intake pump
Stock honda MAP sensor (connected to the t/b in stock location not limited)
Stock honda FPR (off the the fuel rail)
Stock fuel pressure, ~40psi at WOT, increases as car boosts. (1:1)
boost set at 10psi regulated with an apex avcd boost controller
garret t3/t04e .48a/r 54 trim
apex fuel settings are, -40% from 1000-4000rpms, -35% from 5000-8000rpms (to be safe i increased the 5000+ rpms by 5%). The settings are the same on high and low throttle settings.
I dont get a CEL with 10psi of boost, but i do with 11psi. Im sure if i changed my high rpm fuel from -35 to -40 i could squeeze a little more boost outa the system but i dont wanna push my stock mutt engine any father then it already is. But i have been running around with 10psi with this system for a while now without any problems what-so-ever. And i have been really enjoying good gas milage and just awesome throttle responce.
I highly highly highly recommend this setup for anybody that wants a cheap hondata like driveablity without spending the money. Almost everybody has a afc and DSM 450CC injectors are really cheap. Not to mention you dont have to hack anything..just set fuel at -40% and go with it and have the afc wired like its supposted to be.
When i rebuilt my last engine i didnt want to use the secondary injectors (f-max erl mf2 fuel system although i had 550cc secondary injectors not 440cc) anymore and wanted something better. I read about the afc hack and thought i would give it a shot. I have a dsm so finding dsm injectors were easy.
My first impressions once i had it all working is...well it worked! I got the boost up to 9psi and it seemed to work pretty good, at least at WOT. EGT and a/f gauge both showed good numberes, and i was also monitoring the o2 voltage by using the "blue wire mod" on the afc which was also good.
The problems started happening while at 1/2 throttle. I drove my honda to oregon from san diego last week and going up and down through the mountains really sucked. I kept having to change the damn cross over point from vacuum into boost on the afc to match the current altitude so the car wouldnt run lean. But even with the right cross over point the car would start going into boost and the honda computer would change the air/fuel from rich (cuz of the afc) so a leaner value. (thats what close loop mode is all about right?) I could watch the EGT increase as this happened. There was also a stumble as the honda computer fixed this. It was pissing me off to no end.
So for a few hundred miles i was playing with the afc trying to make it better...and i just couldnt get it right. So then the thought came.
The afc hack you use a MAP limiter, and then step up from a negative value for fuel with the afc (i was stepping up to around +5%) once the car starts to boost.
So i was thinking, isnt a limited MAP (with a missing link check valve whatever) and the afc stepped all the way to +5% the same as an unlimited map with the same boost? (that is if i got the damn thing tuned right)
So i pulled into a gas station and modded the fuel system. I removed the missing link so i had an unlimited map. I set my AFC at -40% from 1000rpms to 8000rpms so it would keep it no matter what boost level i was running.
I started the car....and it works. It works really well. Its night and day difference. Its AMAZING. In and out of boost you cant tell the difference from a driving stand point. Transition into boost...well there is no transition..its not there because its that smooth. Its as smooth as my eclipse. 1/2 throttle into boost is the same way. 1st gear burnouts feathering the gas so you dont slam the rev limiter...smooth as silk as if you didnt have a turbo. Its a poor mans hondata only i think its just as good.
EGT, a/f, and o2 voltage are all good also.
I have a friend with a b16a/turbo in a 95 civic coupe running 7-9psi. He was running the afc hack like i was. He drove my car...almost drove it off the road because of the torque steer (hah gotta love the d-series axles) but was really impressed by how smooth it was. We rewired his AFC back to stock removed his check valve set his afc at -40% across the board and took it for a spin. The first words out of his mouth were "wow..what a difference that made..its smooth." His over rich in boost, ugly transitions, and all the other bad side effects were gone. Hes using a p28 chipped ecu with a dohc mugen program.
So this is my currect setup:
d16y7 block with z6 head (hey it was cheap) z6 head gasket
p28 ecu (stock unchipped)
99 Turbo DSM 450CC injectors
89 CRX Si resistor box
Apex AFC fuel computer
Walbro 255 lr/hr high flow intake pump
Stock honda MAP sensor (connected to the t/b in stock location not limited)
Stock honda FPR (off the the fuel rail)
Stock fuel pressure, ~40psi at WOT, increases as car boosts. (1:1)
boost set at 10psi regulated with an apex avcd boost controller
garret t3/t04e .48a/r 54 trim
apex fuel settings are, -40% from 1000-4000rpms, -35% from 5000-8000rpms (to be safe i increased the 5000+ rpms by 5%). The settings are the same on high and low throttle settings.
I dont get a CEL with 10psi of boost, but i do with 11psi. Im sure if i changed my high rpm fuel from -35 to -40 i could squeeze a little more boost outa the system but i dont wanna push my stock mutt engine any father then it already is. But i have been running around with 10psi with this system for a while now without any problems what-so-ever. And i have been really enjoying good gas milage and just awesome throttle responce.
I highly highly highly recommend this setup for anybody that wants a cheap hondata like driveablity without spending the money. Almost everybody has a afc and DSM 450CC injectors are really cheap. Not to mention you dont have to hack anything..just set fuel at -40% and go with it and have the afc wired like its supposted to be.
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Re:
my problem is the wierd sound i have DURING idling. i've no driveability problem yet. i'm just confused why it's making that sound.
i tried setting it at -38, -40 and -35 on the 1k-2k hoping to fix my idling but it's still producing that wierd bop/pop sound.
i know i did the wiring/procedure correctly... i'm running stock pump, 450cc dsm injectors, resistors, NO fmu and NO missing link.
anybody got any idea about the wierd sound?
i tried setting it at -38, -40 and -35 on the 1k-2k hoping to fix my idling but it's still producing that wierd bop/pop sound.
i know i did the wiring/procedure correctly... i'm running stock pump, 450cc dsm injectors, resistors, NO fmu and NO missing link.
anybody got any idea about the wierd sound?
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From: Pembroke Pines, Florida, United States
Re: Re: (Mase)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mase »</TD></TR><TR><TD CLASS="quote">when i tuned leadtrum's ex w/ a wideband, we came out w/ some really different settings. i had to lean idle out almost as much as i could.</TD></TR></TABLE>
yah... mine throughout the rpm band was like -40's then funny was like -43 up top hehe... VaporTrail semi tuned it off 3 pulls... pretty flat *** a/f ratio
yah... mine throughout the rpm band was like -40's then funny was like -43 up top hehe... VaporTrail semi tuned it off 3 pulls... pretty flat *** a/f ratio
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From: ashEVILle, NC, USSR
Re: Re: (_Endless_)
You have a rich idle, you have to learn to live with it. The minimum Honda injector pulsewidth for your ECU is still too big for your injectors. You can fiddle the idle pulse if you are so inclined, but most people seem to get freaked out at the mention of a chip burner.
I used to have to bog my car with fuel at idle, 1K --> -25%, to prevent a pulsation. I know other people who've had similar problems. Bottom line is, your idle quality is probably wierd if you have an AFC hack.
I used to have to bog my car with fuel at idle, 1K --> -25%, to prevent a pulsation. I know other people who've had similar problems. Bottom line is, your idle quality is probably wierd if you have an AFC hack.
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Re: Re:
i just test drive the car this morning but didn't get the chance to really boost(stupid traffic!).
overall, it drives smooth no jerking or anything YET. i do get occasional knock probably due to advance timing. my mechanic said he didn't touch timing when he rebuilt my engine but the distributor is not in the middle position like it used to.
one thing that i don't like so far is the behaviour of my autometer a/f meter. at idle it stayed on the rich side(3 leds from full rich) and whenever i decelerate it goes to lean for a while until the car is no longer decelerating then it goes to rich again. is that normal? is there anything wrong here? any ideas?
by the way, i'm using a 4-wire NTK o2 sensor from a eg civic.
overall, it drives smooth no jerking or anything YET. i do get occasional knock probably due to advance timing. my mechanic said he didn't touch timing when he rebuilt my engine but the distributor is not in the middle position like it used to.
one thing that i don't like so far is the behaviour of my autometer a/f meter. at idle it stayed on the rich side(3 leds from full rich) and whenever i decelerate it goes to lean for a while until the car is no longer decelerating then it goes to rich again. is that normal? is there anything wrong here? any ideas?
by the way, i'm using a 4-wire NTK o2 sensor from a eg civic.
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Joined: May 2002
Posts: 386
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From: cherry hill, nj, USA
Re: just finished hooking up my turbo with the VAFC hack...got a question (_Endless_)
from what u are describing, it sounded just like my car at idle.
like my friends say, "what are you making pop corn?" sort of sounds like that right? but just fainter.... my car was running very rich though. this was with the original dragIII kit. no afc hack yet at the time but got stolen b4 i could get to it.
like my friends say, "what are you making pop corn?" sort of sounds like that right? but just fainter.... my car was running very rich though. this was with the original dragIII kit. no afc hack yet at the time but got stolen b4 i could get to it.
Junior Member
Joined: May 2002
Posts: 386
Likes: 1
From: cherry hill, nj, USA
Re: Re: (_Endless_)
just as turbod16y8 said. the a/f ratio meter only really works at WOT. so ur fine.
also other than the advanced timing, fuel defiency might always be a problem. intank pump may help also w/ ur knock problem....
also other than the advanced timing, fuel defiency might always be a problem. intank pump may help also w/ ur knock problem....
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Re: just finished hooking up my turbo with the VAFC hack...got a question (Sipower99)
sorry to hear bout your car. maybe i was running rich. i don't experience any more knocks at the moment but i'll still retard the timing coz it was advance.
other than these minor problems i've experienced, my car drives way smoother compare to my previous fmu setup. the rpm is quick going up when you step on it. it's like driving a bigger displacement car.
other than these minor problems i've experienced, my car drives way smoother compare to my previous fmu setup. the rpm is quick going up when you step on it. it's like driving a bigger displacement car.
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From: BL, WA
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From: Newark, DE
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From: NYC bitchessss
Re: just finished hooking up my turbo with the VAFC hack...got a question
I didn't look at the date, and was like wtf, people are still telling him to use the hack? Then I saw the date haha
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