Two things...
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Joined: Jan 2004
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From: Coconut Creek
Hey guys, new to the site and have been reading the threads. As stated before the 04's revs. were lowered because of the faster speed of the internals. I agree that by increasing the redline to 9000 rpm's could lead to sever problems as the internals will not be able to handle the increased velocity. I would give the 04 some more time in the open market for tuners to experiment and see what they come up with. The logical solution would be to strengthen the internals (springs and retainers) and maybe the valves as those are going to be the weaker of the links.
With lowering the VTEC engagement, do you not have introduce more fuel at the same points? I'm not familier with those controlers so maybe they also adj. the fuel.
With lowering the VTEC engagement, do you not have introduce more fuel at the same points? I'm not familier with those controlers so maybe they also adj. the fuel.
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Joined: Mar 2004
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From: miami springs
[QUOTE]Originally posted by allan-s2000
Hey guys, new to the site and have been reading the threads. As stated before the 04's revs. were lowered because of the faster speed of the internals. I agree that by increasing the redline to 9000 rpm's could lead to sever problems as the internals will not be able to handle the increased velocity. I would give the 04 some more time in the open market for tuners to experiment and see what they come up with. The logical solution would be to strengthen the internals (springs and retainers) and maybe the valves as those are going to be the weaker of the links.
Hey guys, new to the site and have been reading the threads. As stated before the 04's revs. were lowered because of the faster speed of the internals. I agree that by increasing the redline to 9000 rpm's could lead to sever problems as the internals will not be able to handle the increased velocity. I would give the 04 some more time in the open market for tuners to experiment and see what they come up with. The logical solution would be to strengthen the internals (springs and retainers) and maybe the valves as those are going to be the weaker of the links.
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Joined: Oct 2000
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From: Columbia, MD
allan,
You beat me to the punch on this one. After my last post to Jonathan, I started thinking specifically about the VTEC controller and its effects with the high cams. It's certainly an area I'm ignorant about, but I'm sure an Apex'i tech (or possibly an experienced user) could answer.
Most of the time people go into the tuning process with the idea of lowering their redline from the get-go. They tune, lower it, then tune some more. My questions is more along the lines of what intereaction is there between the ECU and the VTEC cam engagement, particularly when the ECU is not the one directly engaging the cam.
Consider this...the engagement of the high cam introduces longer lift and duration, therefore more air into the cylinders. Now, lower the redline significantly. If there is no interaction, you've just leaned out your A/F mixture to dangerously high levels, possibly into detonation. this isn't as large an issue during typical tuning since it's usually done piecemeal...you lower a bit, adjust the mixture, lower some more, etc.
However, if there IS interaction, even though the VAFC controller engaged the high cam, the ECU recognizes this and increases the injector duty cycle. You still have an issue of a big bang at an odd spark advance time, but maybe this could also be mitigated (but not totally relieved) with a system that is able to modify timing, such as the e-Manage. Go too low, though, and you'll start to see serious lugging, as I mentioned before, and that will tear a cylinder wall and piston skirt to shreds.
In a nutshell, my question is probably more laong the lines of "What kind of interaction is there between the different signals on the ECU?" The VAFC modifies the signals after the fact, but is the ECU smart enough (or even equipped enough) to detect those changes? My guess is "no", since doing so would require a significant increase in sensors, but the fact of the matter is, I just don't know for sure. I'll have to research this one a bit more...
You beat me to the punch on this one. After my last post to Jonathan, I started thinking specifically about the VTEC controller and its effects with the high cams. It's certainly an area I'm ignorant about, but I'm sure an Apex'i tech (or possibly an experienced user) could answer.
Most of the time people go into the tuning process with the idea of lowering their redline from the get-go. They tune, lower it, then tune some more. My questions is more along the lines of what intereaction is there between the ECU and the VTEC cam engagement, particularly when the ECU is not the one directly engaging the cam.
Consider this...the engagement of the high cam introduces longer lift and duration, therefore more air into the cylinders. Now, lower the redline significantly. If there is no interaction, you've just leaned out your A/F mixture to dangerously high levels, possibly into detonation. this isn't as large an issue during typical tuning since it's usually done piecemeal...you lower a bit, adjust the mixture, lower some more, etc.
However, if there IS interaction, even though the VAFC controller engaged the high cam, the ECU recognizes this and increases the injector duty cycle. You still have an issue of a big bang at an odd spark advance time, but maybe this could also be mitigated (but not totally relieved) with a system that is able to modify timing, such as the e-Manage. Go too low, though, and you'll start to see serious lugging, as I mentioned before, and that will tear a cylinder wall and piston skirt to shreds.
In a nutshell, my question is probably more laong the lines of "What kind of interaction is there between the different signals on the ECU?" The VAFC modifies the signals after the fact, but is the ECU smart enough (or even equipped enough) to detect those changes? My guess is "no", since doing so would require a significant increase in sensors, but the fact of the matter is, I just don't know for sure. I'll have to research this one a bit more...
(Redline) with a couple clicks on your laptop keyboard.