BtTurboM3

hi i was wondering....isnt vtec supposed to hit at the redline?

well my freind has a Del Sol with a integra GSR front end conversion. and it also has a GSR motor in it so obviously it has vtec. i was driving it about a week ago and there was a little staright away and after i shifted into second i punched it a little bit and Vtec hit at about 5-6k rpms. and i wasnt expecting that to happen becuase it redlines around 8. so is that normal or is the vtec timing off or different from the conversion. thanks....

see car here:

tegbooster

.... wow ....


the whole point of vtec is to help you through the higher RPMs... your not supposed to be pushing it past redline all that often... if ever. so logically why would vtec hit AT redline.

in any case... no it generally is supposed to activate around 4500 or so... but he probably has it tuned for a bit higher

enjoy.

sherwood

vtec is supposed to come in early, the idea is to suspend the torque curve further. the lower cam lobes are for applications below appx 5k the uppers are for applications above 5k.

now the vtec in that car hits in the late 4's what you were hearing or feeling WAS NOT VTEC it was merely the peak torque of the second camshaft AND the secondary butterflies opening around the same point. (mid 5's into 6k) it can be very decieveing.

in actuality vtec doesnt kick at all. on newer models it seems honda tried to trick people by moving the secondary x-over later than it should be, thus creating something noticible... (this is most evident in cars such as the TSX, RSX and S2000) i presume this is so people can "feel" vtec working (basically it's something to make people feel good about purchasing a vtec car over other cars because vtec actually means something)

on the older cars theres really not much of a jump at all at the vtec x-over and many people chip the newer cars with hondata reflashes because the x-over can be pushed down to create a more useful, smoother, torque curve.

BtTurboM3

ooooooooooooooooooooooooooooo ok

thanks alot man. i just thought i heard that somwhere that your supposed to hit it at the redline. so when i hit it at like 5k i was a little confused.


now i feel dumb....

sherwood

meh we all are sometimes, but come on, what good does it do anyone if you have to shift as soon as you hit it?

Snoopy

might as well get something without vtec at that point

BtTurboM3

thanks guys....lol

sherwood

without VTEC these engines are shot. the low end cam lobes don't make crap after 5k and when they accidentally put a p75 ecu in my car and i had this happen i could barly get it above 6k in third gear.

ADRONICUS

Redline on most cars is the danger zone. Nothing is supposed to happe after that point. VTEC kicks in until redline then the fuel cutout kicks in.

sherwood

no, redline is merely an optimal shift point, afterwhich not enough power is made. most cars are safe going a few hundred past their redline, the fuel cutoff is whats there to stop damage.