The VAFC post
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The VAFC post
Alright, I've seen a lot of debate over this issue, and installing a VAFC in a 7th gen. Some say it won't work, others say it will.
The people I would like to respond are those that ACTUALLY HAVE the VAFC installed. I've read posts where people were able to get it to work in their 7th gen. If I remember correctly, it's because Apexi was able to get the wiring correct finally.
So if you have it, how did you get it to work? Was it simply a matter of waiting til apexi got the proper wiring schematic? What's the deal? What kind of gains were you able to get with tuning??
The people I would like to respond are those that ACTUALLY HAVE the VAFC installed. I've read posts where people were able to get it to work in their 7th gen. If I remember correctly, it's because Apexi was able to get the wiring correct finally.
So if you have it, how did you get it to work? Was it simply a matter of waiting til apexi got the proper wiring schematic? What's the deal? What kind of gains were you able to get with tuning??
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Rep Power: 404 I got it to work by the proper wiring schematic that apexi put out. every thing works right except the check engine light that comes on. i set the v-tec at 4800 and it pulls nicely. i think the way to get the check light off is to tune the air fuel right. i still need to tune mine, i am not sure what to do on the 4 diffrent setting we need to put it on. the high, low, and the settings of the rpm for the 8 stages.
hey s2000man, do you think this will work on your s2000?
hey s2000man, do you think this will work on your s2000?
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Ok, the V-AFC does work. I installed it myself, and it took about one hour. To see where I installed it look below...
Everything on the V-AFC works fine, the VTEC portion works fine, the air/fuel portion works fine(I know because I have an Air/Fuel Gauge).
You can set the VTEC at any point, set at anything above 4500 RPM's, the VTEC crossover point kicks in very hard. Harder then your average B16(DOHC VTEC).
It looks very cool. The only problem with it is the Check engine light problem. To combat this I drive for a few minutes then reset the ECU, and the check engine light goes away. That is the only thing we have to overcome, then the V-AFC will be working fine. I really hate the fact that, that light comes on.
Everything on the V-AFC works fine, the VTEC portion works fine, the air/fuel portion works fine(I know because I have an Air/Fuel Gauge).
You can set the VTEC at any point, set at anything above 4500 RPM's, the VTEC crossover point kicks in very hard. Harder then your average B16(DOHC VTEC).
It looks very cool. The only problem with it is the Check engine light problem. To combat this I drive for a few minutes then reset the ECU, and the check engine light goes away. That is the only thing we have to overcome, then the V-AFC will be working fine. I really hate the fact that, that light comes on.
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Quote
[hr]Originally posted by: HondaLuver
I got it to work by the proper wiring schematic that apexi put out. every thing works right except the check engine light that comes on. i set the v-tec at 4800 and it pulls nicely. i think the way to get the check light off is to tune the air fuel right. i still need to tune mine, i am not sure what to do on the 4 diffrent setting we need to put it on. the high, low, and the settings of the rpm for the 8 stages.
hey s2000man, do you think this will work on your s2000?[hr]
[hr]Originally posted by: HondaLuver
I got it to work by the proper wiring schematic that apexi put out. every thing works right except the check engine light that comes on. i set the v-tec at 4800 and it pulls nicely. i think the way to get the check light off is to tune the air fuel right. i still need to tune mine, i am not sure what to do on the 4 diffrent setting we need to put it on. the high, low, and the settings of the rpm for the 8 stages.
hey s2000man, do you think this will work on your s2000?[hr]
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Rep Power: 0 This is weird- the D series VTEC engagement point is not as high as the B series (ie mid 5000's), so I dont see any gain of using the VAFC other than for fuel ratios...stock engagement is what, 4600 or 4800- so whats the point?
I doubt that...
Quote
[hr]Harder then your average B16(DOHC VTEC).[hr]
[hr]Harder then your average B16(DOHC VTEC).[hr]
so your saying that when the check engine light turns on you just have to reset the ECU. (Disconnecting the battery for 10 min., then running the car for like 5 min.) Then the light will turn off for goodl?
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[hr]This is weird- the D series VTEC engagement point is not as high as the B series (ie mid 5000's), so I dont see any gain of using the VAFC other than for fuel ratios...stock engagement is what, 4600 or 4800- so whats the point?
Quote
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Harder then your average B16(DOHC VTEC).
--------------------------------------------------------------------------------
I doubt that... [hr]
[hr]This is weird- the D series VTEC engagement point is not as high as the B series (ie mid 5000's), so I dont see any gain of using the VAFC other than for fuel ratios...stock engagement is what, 4600 or 4800- so whats the point?
Quote
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Harder then your average B16(DOHC VTEC).
--------------------------------------------------------------------------------
I doubt that... [hr]
Neo, I've driven, a stock 99 SI, a 99 SI with an intake, a RSX type S w/ I/H/E, and a EG hatch w/ a worked B16.
I've ridden in a 2000 Prelude with a decent amount of work, a LS/VTEC Integra, a Supercharged 00 SI, a 98 NBW ITR, so I know how VTEC crossover in a DOHC is.
Trust me when I say it kicks in just as hard as some of the cars I listed. But I know you don't believe me, that's why in a few weeks I'll put up a video.
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[hr]Well, in our D series motor, the VTEC actually engages at about 4k. The reason for a B series to have a higher crossover point is because it has a higher redline, Honda decided that since we are not as performance oriented stuck us with a lower engagement point and a lower redline(There are other reasons).[hr]
[hr]Well, in our D series motor, the VTEC actually engages at about 4k. The reason for a B series to have a higher crossover point is because it has a higher redline, Honda decided that since we are not as performance oriented stuck us with a lower engagement point and a lower redline(There are other reasons).[hr]
Quote
[hr]I've driven, a stock 99 SI, a 99 SI with an intake, a RSX type S w/ I/H/E, and a EG hatch w/ a worked B16.I've ridden in a 2000 Prelude with a decent amount of work, a LS/VTEC Integra, a Supercharged 00 SI, a 98 NBW ITR, so I know how VTEC crossover in a DOHC is.
Trust me when I say it kicks in just as hard as some of the cars I listed. But I know you don't believe me, that's why in a few weeks I'll put up a video. [hr]
[hr]I've driven, a stock 99 SI, a 99 SI with an intake, a RSX type S w/ I/H/E, and a EG hatch w/ a worked B16.I've ridden in a 2000 Prelude with a decent amount of work, a LS/VTEC Integra, a Supercharged 00 SI, a 98 NBW ITR, so I know how VTEC crossover in a DOHC is.
Trust me when I say it kicks in just as hard as some of the cars I listed. But I know you don't believe me, that's why in a few weeks I'll put up a video. [hr]
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[hr]Originally posted by: NeoMagus
I know. I had a VAFC on my EM1.
Then somethings wrong with your butt dyno if you believe a single cam 127hp motor is pulling harder than a B, H, or K series motor that youve driven. But hey whatever man if it feels good for you then [hr]
[hr]Originally posted by: NeoMagus
Quote
[hr]Well, in our D series motor, the VTEC actually engages at about 4k. The reason for a B series to have a higher crossover point is because it has a higher redline, Honda decided that since we are not as performance oriented stuck us with a lower engagement point and a lower redline(There are other reasons).[hr]
[hr]Well, in our D series motor, the VTEC actually engages at about 4k. The reason for a B series to have a higher crossover point is because it has a higher redline, Honda decided that since we are not as performance oriented stuck us with a lower engagement point and a lower redline(There are other reasons).[hr]
Quote
[hr]I've driven, a stock 99 SI, a 99 SI with an intake, a RSX type S w/ I/H/E, and a EG hatch w/ a worked B16.I've ridden in a 2000 Prelude with a decent amount of work, a LS/VTEC Integra, a Supercharged 00 SI, a 98 NBW ITR, so I know how VTEC crossover in a DOHC is.
Trust me when I say it kicks in just as hard as some of the cars I listed. But I know you don't believe me, that's why in a few weeks I'll put up a video. [hr]
[hr]I've driven, a stock 99 SI, a 99 SI with an intake, a RSX type S w/ I/H/E, and a EG hatch w/ a worked B16.I've ridden in a 2000 Prelude with a decent amount of work, a LS/VTEC Integra, a Supercharged 00 SI, a 98 NBW ITR, so I know how VTEC crossover in a DOHC is.
Trust me when I say it kicks in just as hard as some of the cars I listed. But I know you don't believe me, that's why in a few weeks I'll put up a video. [hr]
[hr]
But run them side by side, and you see the butt dyno lies.
I think that's what NeoMagus is trying to say.
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From: akron, Other, ZEBRA
Rep Power: 0 can someone please e-mail me the most current wiring instructions, I cant seem to access apexi's website. I'll need the newest one that allows the vtec controller to work. I guess the older instructions had some wires that were not in the manual. Thanks
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Quote
[hr]Originally posted by: NeoMagus
I know. I had a VAFC on my EM1.
Then somethings wrong with your butt dyno if you believe a single cam 127hp motor is pulling harder than a B, H, or K series motor that youve driven. But hey whatever man if it feels good for you then [hr]
[hr]Originally posted by: NeoMagus
Quote
[hr]Well, in our D series motor, the VTEC actually engages at about 4k. The reason for a B series to have a higher crossover point is because it has a higher redline, Honda decided that since we are not as performance oriented stuck us with a lower engagement point and a lower redline(There are other reasons).[hr]
[hr]Well, in our D series motor, the VTEC actually engages at about 4k. The reason for a B series to have a higher crossover point is because it has a higher redline, Honda decided that since we are not as performance oriented stuck us with a lower engagement point and a lower redline(There are other reasons).[hr]
Quote
[hr]I've driven, a stock 99 SI, a 99 SI with an intake, a RSX type S w/ I/H/E, and a EG hatch w/ a worked B16. I've ridden in a 2000 Prelude with a decent amount of work, a LS/VTEC Integra, a Supercharged 00 SI, a 98 NBW ITR, so I know how VTEC crossover in a DOHC is.
Trust me when I say it kicks in just as hard as some of the cars I listed. But I know you don't believe me, that's why in a few weeks I'll put up a video. [hr]
[hr]I've driven, a stock 99 SI, a 99 SI with an intake, a RSX type S w/ I/H/E, and a EG hatch w/ a worked B16. I've ridden in a 2000 Prelude with a decent amount of work, a LS/VTEC Integra, a Supercharged 00 SI, a 98 NBW ITR, so I know how VTEC crossover in a DOHC is.
Trust me when I say it kicks in just as hard as some of the cars I listed. But I know you don't believe me, that's why in a few weeks I'll put up a video. [hr]
[hr]
Quote
[hr]Originally posted by: Shlomo
so your saying that when the check engine light turns on you just have to reset the ECU. (Disconnecting the battery for 10 min., then running the car for like 5 min.) Then the light will turn off for goodl?[hr]
[hr]Originally posted by: Shlomo
so your saying that when the check engine light turns on you just have to reset the ECU. (Disconnecting the battery for 10 min., then running the car for like 5 min.) Then the light will turn off for goodl?[hr]
thx in advanced.
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PLEASE someone tell me where I can get the latest wiring diagram to get the vtec controller working!! My unit came with a old manual and is of no use
PLEASE someone tell me where I can get the latest wiring diagram to get the vtec controller working!! My unit came with a old manual and is of no use
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Rep Power: 0 The check engine light will come on anytime you turn on your car after leaving it for a while, I believe this can be changed by putting a switch to your VTEC wire, which I will be doing and keeping you guys updated.
Apexi-usa.com, has the wiring diagram there.
Apexi-usa.com, has the wiring diagram there.
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Rep Power: 0 Also, use this in conjunction with what I have sent you...
Click here!
Click here!
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From: Lewisville (Dallas), Texas, US
Rep Power: 0 Correct me if I'm wrong, but isn't the whole point of VTEC adjustment so you can tune when the cam changes from the low rpm profile to the high rpm profile when the low rpm profile begins to leave it's powerband? If that's the case then wouldn't the ideal situation be to tune the VTEC engagement point at the peak of the low rpm profile, therefore minimizing the jolt you feel when VTEC engages due to the fact that the profile switch takes place before the low rpm profile begins to lose power?
Quote
[hr]Originally posted by: DRJ
Correct me if I'm wrong, but isn't the whole point of VTEC adjustment so you can tune when the cam changes from the low rpm profile to the high rpm profile when the low rpm profile begins to leave it's powerband? If that's the case then wouldn't the ideal situation be to tune the VTEC engagement point at the peak of the low rpm profile, therefore minimizing the jolt you feel when VTEC engages due to the fact that the profile switch takes place before the low rpm profile begins to lose power?[hr]
[hr]Originally posted by: DRJ
Correct me if I'm wrong, but isn't the whole point of VTEC adjustment so you can tune when the cam changes from the low rpm profile to the high rpm profile when the low rpm profile begins to leave it's powerband? If that's the case then wouldn't the ideal situation be to tune the VTEC engagement point at the peak of the low rpm profile, therefore minimizing the jolt you feel when VTEC engages due to the fact that the profile switch takes place before the low rpm profile begins to lose power?[hr]
good theory, but i personally want to feel that jolt when vtec engages. and the low rpm profile would not lose power because right before you think it would, it switches to the high rpm profile.... you know what i'm getting at?
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Rep Power: 0 That's just it though...the larger the jolt, the longer the engine has been on the low rpm cam profile when it should have switched. If you tune the car correctly, you don't get both the jolt and the increased power.
My point is that you can increase the "kick" of VTEC, but usually the end result is a loss of midrange power, which IMO, is bad.
My point is that you can increase the "kick" of VTEC, but usually the end result is a loss of midrange power, which IMO, is bad.
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Quote
[hr]Correct me if I'm wrong, but isn't the whole point of VTEC adjustment so you can tune when the cam changes from the low rpm profile to the high rpm profile when the low rpm profile begins to leave it's powerband? If that's the case then wouldn't the ideal situation be to tune the VTEC engagement point at the peak of the low rpm profile, therefore minimizing the jolt you feel when VTEC engages due to the fact that the profile switch takes place before the low rpm profile begins to lose power? [hr]
[hr]Correct me if I'm wrong, but isn't the whole point of VTEC adjustment so you can tune when the cam changes from the low rpm profile to the high rpm profile when the low rpm profile begins to leave it's powerband? If that's the case then wouldn't the ideal situation be to tune the VTEC engagement point at the peak of the low rpm profile, therefore minimizing the jolt you feel when VTEC engages due to the fact that the profile switch takes place before the low rpm profile begins to lose power? [hr]
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From: Car Audioville, Quebec, Canada
Rep Power: 0 Vtec is pretty much designed for one thing... Balanced power...
Low end torque, and high end torque..
If the cam profiling remained the same as the low RPM setting you'd start to lose torque after abour 5000rpms and your HP would level out instead of rise..
the DX/LX's actually have more midrange power than EX's because of their cam profiling.
For racing applications VTEC is useless as yu'll always be in the agressive cam mode..all it would do is allow for a relatively smooth idle..
Great for daily drivers though...good for fuel economy and getting around...and good for some extra fun when you get the engine revving up.
In the new civics VTEC accounts for about 5HP, the higher compression ratio does the rest.
Low end torque, and high end torque..
If the cam profiling remained the same as the low RPM setting you'd start to lose torque after abour 5000rpms and your HP would level out instead of rise..
the DX/LX's actually have more midrange power than EX's because of their cam profiling.
For racing applications VTEC is useless as yu'll always be in the agressive cam mode..all it would do is allow for a relatively smooth idle..
Great for daily drivers though...good for fuel economy and getting around...and good for some extra fun when you get the engine revving up.
In the new civics VTEC accounts for about 5HP, the higher compression ratio does the rest.
Quote
[hr]Originally posted by: mrdan4548
so i dont see how this post is helpin out. Did anyone find out how to keep the check engine light from comin on or not? Or why it comes on at all?[hr]
[hr]Originally posted by: mrdan4548
so i dont see how this post is helpin out. Did anyone find out how to keep the check engine light from comin on or not? Or why it comes on at all?[hr]
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From: Chicago Burbs, Other, ZEBRA
Rep Power: 528 How does adding a VAFC improve your:
0-60mph times?
1/4 mile times?
50-70mph times (for passing and stuff)?
These are what would determine if I buy one or not.
Good thread, btw.
IronFist
0-60mph times?
1/4 mile times?
50-70mph times (for passing and stuff)?
These are what would determine if I buy one or not.
Good thread, btw.
IronFist
heres something about check engine light on apexi's website.
Q: VAFC: I have finished installing my VAFC but whenever I drive my car around, the Check Engine light comes on.
A: 1. Make sure that the VTM signal wire has been connected. This wire must be conected on all US spec Honda's. Please refer to the Documentation section of this website.
2. If the settings on the VAFC under wide and narrow throttle have been set beyond +12~14% at any point, it will cause the ECU to believe that the car is under boost. This will trigger the MAP sensor error.
3. Make sure that the pressure sensor type is set to 6 IN and 6 OUT. This can be adjusted on the Sensor Type menu of the unit.
try that out, see if that helps......
Q: VAFC: I have finished installing my VAFC but whenever I drive my car around, the Check Engine light comes on.
A: 1. Make sure that the VTM signal wire has been connected. This wire must be conected on all US spec Honda's. Please refer to the Documentation section of this website.
2. If the settings on the VAFC under wide and narrow throttle have been set beyond +12~14% at any point, it will cause the ECU to believe that the car is under boost. This will trigger the MAP sensor error.
3. Make sure that the pressure sensor type is set to 6 IN and 6 OUT. This can be adjusted on the Sensor Type menu of the unit.
try that out, see if that helps......
