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/me thinks pclee is on the crack - I have no idea what the Q is either.
BTW - adjusting the VTEC engagement is bad. I don't care what a dyno shows - I've seen the boys at Croydon make a dyno show a stocl old-school VW show 100kw @RW.
It is a bad thing to do - end of story.
There are 4 engagement points. i think this is what pcglee is getting up.
VTEC engages while revving up, and also while revving down.
High engement means from redline -> 0rpm,. when should the cam kick in, and when it should dis-engage.
I think he means at what RPM does the high cam lobe actuator pin engage... ?
VTEC on the B16A2 cuts in at 5500rpm, when its not in VTEC the ecu reads the low speed fuel and timming maps in the rom, when VTEC is engaged then the ecu reads the high speed fuel and ignition maps. changing the vtec point with aftermarket equipment will not change the fuel maps so its a big waist of time. vtec point can be changed on a factory ecu by editing the ROM data.
4 things determin VTEC engagement
- engine temperature
- engine load
- vehicle speed
- throttle position
mine definately kicks in at about 5650 dude.
what i mean is that..
why after market cams has a higher RPM of engagement on Vtec....
but the standard ones are only at around 5800rpm....and i know lots of people set it at 4500rpm...or 5000rpm...why is that?...does it do alot of goods??
by the way..mine kicks in at 7400rpm...but why?....
is the question clear enough...
and by the way setanta...very funny...
and by the way...i'm talking bout Vtec...not VW....look clearly before answering...
if me question still isn't clear enough...then thats alrite...
and yes...is got something to do with the power band as well...
but why higher and why lower??..hmmm....still confusing me...
Tell us what mods etc are done to the car and we'll tell you WHY.Quote:
Originally Posted by pgclee
HOLY CRAP! 7400 :P are you sure your not talking about the red line on the dash :P You still havnt told us anything about your car. At all.
The 4500 Vtec enguagment point has been answered. It doesnt work!
Think of it this way, if you've got a opening into a stadium, and your letting 10 people in at once through the entrance, and they go through fine and all 10 fit fine, now you open up the gate bigger and let through 10 people at a time, you arn't letting more people through, theres still only 10 people going through the gate. Thats whats happening when you lower the VTEC enguagment point, your opening the valve wider and longer, but the same amount of fuel is going through. So the power should platou.
In answer to why they do it! They're uneducated idiots who were coned into buying the unit, that or they have mods that can cope with a change of VTEC cross over.
I hope that answered one of your questions.
The VW thing is to prove a point... Dynos mean Shit! they give you an IDEA of what you've got, dont take it as gosple.
If your VTEC is kicking in at 7400 and your engine is stock, theres a problem. coz that would mean you've got what, 600-800RPM in VTEC.
Also What engine you have would be great information :D
PGCLEE: you're making absolutly no sense.
The reason why aftermarket cams "may" have higher VTEC engagement points is because the cam profile is not the same as the stock cams. This means that the aftermarket cams will benefit from adjusting and tuning to find the most appropiate point at which to switch.
Also most aftermarket cams will have the ability to rev higher than stock cams thus VTEC must be set higher in order to take advantage of the added RPM.
But even on my B18C stock cams my secondaries (VTEC) open up at 5300 which was "at the time" the best point at which James decided to set it at. On the stock ECU VTEC engagement is at 5800.
In summary your question should read: When is it necessary to switch VTEC engagement?
Sorry if some of this doesnt make sense its late and I h\just came from watching a 3 hour movie :P
Thats a bit confusing........usually when people say 'secondaries' they reffer to the secondary intake runners and NOT the VTEC cam lobes/actuator.Quote:
Originally Posted by LatinoHatchCrap
Also, from what I have heard, Hondata can't activate the secondary intake runners(?)
no it doesn't do it a lot of good. Except sound comes in earlier. that great sound of the 2nd cam phase.Quote:
Originally Posted by pgclee
Quote:
Originally Posted by Setanta
Quote:
Originally Posted by SIKCVC
i don't take it as gospel. 100kW or 10kW. i didn't post my dyno graph as to show that i produced so many kW. It was to show that VTEC engagement points have changed, of which seems to be from changing my exhaust system.Quote:
Originally Posted by ECU-MAN
i haven't adjusted the VTEC engagement point or had the ECU ROM edited since having the conversion done either.
As far as dyno goes....if CRD or anyone can manipulate the curve/peak of the dyno graph, it doesn't matter, as now VTEC engages around 4.8k - 5.2k rpm WOT. dyno graph or not, it used to be 5.5k-6k rpm WOT with old exhaust system, & now is lower.
Am running rich atm. would that have anything to do with it ?
Some people lower the vtec point to smooth out vtec engagement. Someone was explaining to me that on a dyno graph, after vtec kicks in, the power dips down for a little bit and then starts to climb up again straight after. The lowering of the vtec point is to smooth out this dip and make your powerband more linear.
Why not just get vtec killer cams? ;) at least you won't be worrying about when vtec kicks in.