vtec on when cruising on the freeway, does fuel economy suffer
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Originally Posted by s2000Junky
Are you running a Neo or Vafc2? That's not how the vafc works and I would be surprised if the NEO is any different, but I cant say for sure since Ive never tuned a NEO. Did he modify/custom wire in the unit to have connectivity to vtec pressure switch or see manifold pressure?
On the vafc/vafc2 its still all rpm engagement based, its just the HI vtec setting tells it when to engage at accelerating rpm and the low setting tells the ecu at what rpm for vtec to disengage on decel, no matter what the throttle load is. For example, if you set vtec to come on/HI at 6k rpm on the vafc, but set LOW to engage at 4k rpm, then vtec would stay on the whole time you were driving around above 4k rpm, but as soon as you let the rpms drop past 4k vtec would come off and you would have to accelerate back up to 6k rpm again before vtec would come back on. So hi/lo only sets up the 'rpm window" of where you can be on and off the gas without disengagement. Typically you would run the Low setting to the closets rpm from HI cam which is in 100rpm increments (at least on the vafc2) so HI 4500/LO 4400 for example.
I ran and tuned one of these on my own car for years. Used it NA and then on a lower boost level SC. Its been a few years but I still remember its functions and quarks pretty thoroughly. Not many run them any more nor understand them fully if they do, so its likely getting harder to find sound information on them unless you go back a few years on some searches. If you go back too far circa 2000-2004 you will get a lot of software engineer brainiacs posing theories and adding a lot of typical convoluted information which can just add to the confusion of an otherwise very simple functioning device. There are a lot of other parameter functions on the menu of this unit which does nothing on the S2k though, which can add to some confusion to the new owner, but just simplify the tuning on the more well versed. There really is only 3 parameters you are effecting, Wide throttle AFR, VTEC rpm on/off and throttle percentage. Everything else should be ignored.
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Joined: Jun 2010
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From: Toronto
Originally Posted by s2000Junky
Are you running a Neo or Vafc2? That's not how the vafc works and I would be surprised if the NEO is any different, but I cant say for sure since Ive never tuned a NEO. Did he modify/custom wire in the unit to have connectivity to vtec pressure switch or see manifold pressure?
On the vafc/vafc2 its still all rpm engagement based, its just the HI vtec setting tells it when to engage at accelerating rpm and the low setting tells the ecu at what rpm for vtec to disengage on decel, no matter what the throttle load is. For example, if you set vtec to come on/HI at 6k rpm on the vafc, but set LOW to engage at 4k rpm, then vtec would stay on the whole time you were driving around above 4k rpm, but as soon as you let the rpms drop past 4k vtec would come off and you would have to accelerate back up to 6k rpm again before vtec would come back on. So hi/lo only sets up the 'rpm window" of where you can be on and off the gas without disengagement. Typically you would run the Low setting to the closets rpm from HI cam which is in 100rpm increments (at least on the vafc2) so HI 4500/LO 4400 for example.
I ran and tuned one of these on my own car for years. Used it NA and then on a lower boost level SC. Its been a few years but I still remember its functions and quarks pretty thoroughly. Not many run them any more nor understand them fully if they do, so its likely getting harder to find sound information on them unless you go back a few years on some searches. If you go back too far circa 2000-2004 you will get a lot of software engineer brainiacs posing theories and adding a lot of typical convoluted information which can just add to the confusion of an otherwise very simple functioning device. There are a lot of other parameter functions on the menu of this unit which does nothing on the S2k though, which can add to some confusion to the new owner, but just simplify the tuning on the more well versed. There really is only 3 parameters you are effecting, Wide throttle AFR, VTEC rpm on/off and throttle percentage. Everything else should be ignored.
On the vafc/vafc2 its still all rpm engagement based, its just the HI vtec setting tells it when to engage at accelerating rpm and the low setting tells the ecu at what rpm for vtec to disengage on decel, no matter what the throttle load is. For example, if you set vtec to come on/HI at 6k rpm on the vafc, but set LOW to engage at 4k rpm, then vtec would stay on the whole time you were driving around above 4k rpm, but as soon as you let the rpms drop past 4k vtec would come off and you would have to accelerate back up to 6k rpm again before vtec would come back on. So hi/lo only sets up the 'rpm window" of where you can be on and off the gas without disengagement. Typically you would run the Low setting to the closets rpm from HI cam which is in 100rpm increments (at least on the vafc2) so HI 4500/LO 4400 for example.
I ran and tuned one of these on my own car for years. Used it NA and then on a lower boost level SC. Its been a few years but I still remember its functions and quarks pretty thoroughly. Not many run them any more nor understand them fully if they do, so its likely getting harder to find sound information on them unless you go back a few years on some searches. If you go back too far circa 2000-2004 you will get a lot of software engineer brainiacs posing theories and adding a lot of typical convoluted information which can just add to the confusion of an otherwise very simple functioning device. There are a lot of other parameter functions on the menu of this unit which does nothing on the S2k though, which can add to some confusion to the new owner, but just simplify the tuning on the more well versed. There really is only 3 parameters you are effecting, Wide throttle AFR, VTEC rpm on/off and throttle percentage. Everything else should be ignored.
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From: Toronto
To the OP,
Open up your Haltech ECU manager software and open your tune. In the toolbar, go to Setup, then click "Main Setup". On the left hand side, click "Outputs". Then, click the "ACF" tab. This table is used to define how your Haltech controls VTEC. Take a screenshot, and post it.
Open up your Haltech ECU manager software and open your tune. In the toolbar, go to Setup, then click "Main Setup". On the left hand side, click "Outputs". Then, click the "ACF" tab. This table is used to define how your Haltech controls VTEC. Take a screenshot, and post it.
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Shit what a waste of breath 
I guess I just assumed due to the symptoms stated in title it had to be a simple VAFC, little did I know it was something more advanced that just waste tuned properly. Well for any VAFC guys that stumble on to this thread, there you go 
I guess I just assumed due to the symptoms stated in title it had to be a simple VAFC, little did I know it was something more advanced that just waste tuned properly. Well for any VAFC guys that stumble on to this thread, there you go
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TL;DR but Junky - The Apexi Neo actually does have a setting to where VTEC engagement will depend on BOTH RPM and throttle position.
You set a RPM when it would engage (let's say 4,800 RPM) and you also set a minimum throttle position at which it would engage (let's say 45%).
So if your throttle position is greater than 45% and your RPMs raise above 4,800 then VTEC kicks in yo! But if you're only cruising with the throttle at 25% and you cross over the 4,800 RPM boundary, the Neo is smart enough to keep you on the low cam because both VTEC conditions have not been met.
I know for certain this is how the Neo operates, as I set mine up and tinkered with every screen on that thing while on the dyno. This throttle position setting must have been a new feature for the Neo.
You set a RPM when it would engage (let's say 4,800 RPM) and you also set a minimum throttle position at which it would engage (let's say 45%).
So if your throttle position is greater than 45% and your RPMs raise above 4,800 then VTEC kicks in yo! But if you're only cruising with the throttle at 25% and you cross over the 4,800 RPM boundary, the Neo is smart enough to keep you on the low cam because both VTEC conditions have not been met.
I know for certain this is how the Neo operates, as I set mine up and tinkered with every screen on that thing while on the dyno. This throttle position setting must have been a new feature for the Neo.
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TL;DR but Junky - The Apexi Neo actually does have a setting to where VTEC engagement will depend on BOTH RPM and throttle position.
You set a RPM when it would engage (let's say 4,800 RPM) and you also set a minimum throttle position at which it would engage (let's say 45%).
So if your throttle position is greater than 45% and your RPMs raise above 4,800 then VTEC kicks in yo! But if you're only cruising with the throttle at 25% and you cross over the 4,800 RPM boundary, the Neo is smart enough to keep you on the low cam because both VTEC conditions have not been met.
I know for certain this is how the Neo operates, as I set mine up and tinkered with every screen on that thing while on the dyno. This throttle position setting must have been a new feature for the Neo.
You set a RPM when it would engage (let's say 4,800 RPM) and you also set a minimum throttle position at which it would engage (let's say 45%).
So if your throttle position is greater than 45% and your RPMs raise above 4,800 then VTEC kicks in yo! But if you're only cruising with the throttle at 25% and you cross over the 4,800 RPM boundary, the Neo is smart enough to keep you on the low cam because both VTEC conditions have not been met.
I know for certain this is how the Neo operates, as I set mine up and tinkered with every screen on that thing while on the dyno. This throttle position setting must have been a new feature for the Neo.
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