Preffered Vtec engagement rpm?
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Vampyre VTi
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not really !
the principle is that as the rpm of an engine increases it struggles to let fuel in and out of the chamber, the VTEC system combats this as it is set to a point where the valves have reached a level where they struggle to shift their load and so altering their timing means that they can adjust the speed in which they operate! this gives gains in performance and in the rev range
VTEC controllers would work a dream in a car that has had new cams fitted, though it woudl still need someone "who knows" to set it up properly!
altering the cut in point otherwise .... there maybe small possible gains altering the cut in point to 5000 ( as you have said), but any lower than that then you could adversly adjust the timing so that the valves would be moving to fast for the rev range to be of any benefit!
someone correct me if im wrong
the principle is that as the rpm of an engine increases it struggles to let fuel in and out of the chamber, the VTEC system combats this as it is set to a point where the valves have reached a level where they struggle to shift their load and so altering their timing means that they can adjust the speed in which they operate! this gives gains in performance and in the rev range
VTEC controllers would work a dream in a car that has had new cams fitted, though it woudl still need someone "who knows" to set it up properly!
altering the cut in point otherwise .... there maybe small possible gains altering the cut in point to 5000 ( as you have said), but any lower than that then you could adversly adjust the timing so that the valves would be moving to fast for the rev range to be of any benefit!
someone correct me if im wrong
So you typed all that and then admit that you don't really know what you're talking about? :roll:Vampyre VTi said:not really !
someone correct me if im wrong
Greg wasn't asking about a VTEC controller, he was asking about VTEC crossover point in the context of mapping a K-Pro.
The i-VTEC system in the K-series is quite a bit different to the old-school system. The crossover point depends on the power curves for each set of lobes at different angles, the tuner will plot the best map across the range of angles as the revs increase and set the crossover point accordingly. There's a window of engagement such that the crossover point depends on inlet manifold pressure, ie it's lower at full throttle and vice versa.
To answer the question I have a feeling that my window is 4200-5800, but can't remember exactly, sorry. It all depends on the other mods you've got and tbh I'd just leave it to the tuner and not worry about it.
Vampyre VTi
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LOLEvs said:
.... i got side tracked as i was typing it! sorry!..i was thinking of a vtec controller at the time! no need to get all arsey!!thanks for the pointer on the Kseries... i'll admit i wasnt aware it was totally different formthe old school!
essentially the principal is the same though the K series appears to manage it much more "i"ntelligently!
gregb
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Tbh before kpro the vtec was more extreme at engagement.
you had alot happenning in sync and although the wait was till 6000rpm
it was worth it.
just the old vtec characteristics have gone with the kpro,while it`s vtec window has been widened and lowered does it give that much benefit in doing so.
it`s still when your in it, just it`s a different ballgame.
going to get it set back to 4500rpm soon.
suppose it varies from tuners rather than owners.
ps:kpro for saleyeah right!!!!!
you had alot happenning in sync and although the wait was till 6000rpm
it was worth it.
just the old vtec characteristics have gone with the kpro,while it`s vtec window has been widened and lowered does it give that much benefit in doing so.
it`s still
when your in it, just it`s a different ballgame.going to get it set back to 4500rpm soon.
suppose it varies from tuners rather than owners.
ps:kpro for saleyeah right!!!!!
Tbh you've hit the nail on the head there.gregb said:
The remap gives you more midrange torque and smooths out the curve, more area underneath = a more accelerative car. End of.
...but not quite. Part of the fun, driving pleasure and satisfaction is keeping the car on the boil when, if you get it wrong, you drop off cam and chug along slowly on the shopping cams. So the on/off VTEC transition with the OEM ECU (and with the old-skool B/F/H- series engines) can actually add to the driving enjoyment. By being not as good... :? :wink: :lol:
I took a current DC2 owner (and old-skool Honda nut) out in mine a few months ago and he asked whether it could be mapped to give a more obvious VTEC changeover... :roll: but 8)
Maybe the solution is two maps: a day to day map with a nice smooth midrange and no 'step' on transition, that you can change up at 6.5-7k and still go reasonably quickly. And a balls-out thrash map with a big step and a torque dip at 5.5k, that you've got to rev out or it tells you in no uncertain terms when you've got it wrong...
:-k :idea:
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The OEM honda map has a big power dip right before the vtec point purposly to make the vtec engagement much more obvious.
this is ironed out by kpro but you should deffinatly know when its in, due to the noise.
Honda could have done this quite easily but didn't probably to give the car owner the vtec feeling.
this is ironed out by kpro but you should deffinatly know when its in, due to the noise.
Honda could have done this quite easily but didn't probably to give the car owner the vtec feeling.
Its not really a dip, but the power levels of, then VTEC comes in. The power has a constant increase until just before VTEC then levels off, does not seem to decrease, then VTEC comes in and there is a sharp spike of increased power.
This happended on my VX220's just before 3500rpm also, mainly for emission control. Also on my DC2. Like you said can be ironed out to make the power more liner*. Ive driven a DC2 car mapped on DTA with a very very smooth power curve, pretty amazing looking at it, but it was not asmuch fun as one where VTEC cam in harder, without the ironing out of power development before VTEC. But saying that, if you driving a VTEC properly, it should stay in VTEC.
At the mo i do feel like having my VTEC point lowered but will leave it and see what it feels like once the JRSC is on.
This happended on my VX220's just before 3500rpm also, mainly for emission control. Also on my DC2. Like you said can be ironed out to make the power more liner*. Ive driven a DC2 car mapped on DTA with a very very smooth power curve, pretty amazing looking at it, but it was not asmuch fun as one where VTEC cam in harder, without the ironing out of power development before VTEC. But saying that, if you driving a VTEC properly, it should stay in VTEC.
At the mo i do feel like having my VTEC point lowered but will leave it and see what it feels like once the JRSC is on.
dan the man
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end of the day with or without KPRO u know when its in as 'feel' it spurring on the acceleration... its kinda like in 6th in it...Its not as noticable as lower gears as hard to pull but its there..the engine just trys that little bit harder and keeps it up.
I reckon i could guess it without a rev counter
I reckon i could guess it without a rev counter