Hey guys i just wanted to know what RPM a stock Integra GS-R DC2 would cross into VTEC. I tried searching but the only thing i get is about Type-R motors and LS/vtecs. So any input is appreciated thanks.

 

6k

 

nah that's wrong.. it's around 4400 to 4500rpms when vtec comes on, then at about 5800 to 6k the intake manifold butterflies open up to the short runners...

on a stock gsr you might not even hear vtec, but you'll hear the intake manifold open up in the higher rpms..

 

Really? i thought that it engaged early but i wasnt sure. i know for sure it opens at 6 k when you can really hear it but i do hear it get slightly loud at like 4500-4500. Can you explain why and how that works?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bkmc24 &raquo;</TD></TR><TR><TD CLASS="quote">Really? i thought that it engaged early but i wasnt sure. i know for sure it opens at 6 k when you can really hear it but i do hear it get slightly loud at like 4500-4500. Can you explain why and how that works?</TD></TR></TABLE>


yeah thats right.. when you hear it around 4400/4500k that is vtec.. around 5800/6k is the IAB's..

i could only find a pic of the F22/H22 IAB system but it gives you an ideal of how it works...
it's main purpose is to give you more low end/ midrange power for daily driving, when you take it to the higher rpms it opens up the butterflies to the shorter larger intake manifold ports to flow better..

 

Okay, so instaling a Vafc, what exactly does it do to engage VTEC earlier if it is already engaged at 4500? do it open the runners ealier as well or something?

Loving HT, i learn something new almost every day!

 

the vafc is used to raised the vtec crossover.. its basically a tuning device.. its not needed unless u have upgraded intake mani or cams.. then u gonna need to raise the vtec xover to avoid bogging

 

Okay, so its basically pointless to have a VAFC on a GSR with i/h/e then huh lol

 

pretty much ditto to what skunk2vtec posted..

on a stock gsr a vtec controller isn't needed..

 

It still doesnt make 100% sense to me, if vtec is already engaged at 4500, then how do people lower thier engagement and its all the way open at 4k like it would be on a stock engagement? does that make sense?

 

Well, if their engine likes Vtec at 4,000 RPM... That woudl have to be determined on a dyno and depends on their setup.


http://www.team-integra.net/se...ID=45
^^^^^^^^^^

Explains in details how Vtec works..

 

I know how vtec works kind of lol

love this site, off topic, whos going to nashville import alliance

 

vtec kicks in at 4400rpm's at FULL throttle is what i heard, so it might not kick in right at 4400 if your not at full throttle.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bkmc24 &raquo;</TD></TR><TR><TD CLASS="quote">It still doesnt make 100% sense to me, if vtec is already engaged at 4500, then how do people lower thier engagement and its all the way open at 4k like it would be on a stock engagement? does that make sense?</TD></TR></TABLE>

No, it honestly isn't clear what you're asking. On a stock GS-R, the VTEC point is 4400 RPM. If you install a V-AFC, the unit sends its own signal to the VTEC solenoid at whatever RPM you specify, thus activating VTEC. Keep in mind though, that while the V-AFC can physically engage VTEC via the solenoid signal, the ECU's VTEC fuel and ignition maps will not be utilised until 4400 RPM.

 

KevLo... Read this: http://www.team-integra.net/se...ID=45
Very informational.
Tells that the VTEC solenoid itself activates at 4400 RPM, then the manifold opens secondary butterfly valves at 5800 RPM to allow more airflow... this greater airflow accounts for most of what you hear.

 

isnt there a difference between obd1 and obd2

i heard that vtec for obd1 kicks in at 4400

and obd2 have two stages 4400 then 5800

would obd1 be faster because everything kicks in at 4400?

please correct me

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LTgsr &raquo;</TD></TR><TR><TD CLASS="quote">isnt there a difference between obd1 and obd2

i heard that vtec for obd1 kicks in at 4400

and obd2 have two stages 4400 then 5800

would obd1 be faster because everything kicks in at 4400?

please correct me </TD></TR></TABLE>

No. All of the '94+ GS-R's have a 4400 RPM VTEC point and secondary butterflies that open at 5750 RPM. None have "two stage" VTEC.

 

just so everyone is clear, like padawan said there is no two stage vtec. there's vtec at 4400 and the intake secondaries at 5750-5800, which are not part of the vtec system.

 

Okay, so installing the VAFC, can that open the secondary butterflies eearly so your all the way open at say 4k? i think thats what i ment to ask lol

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bkmc24 &raquo;</TD></TR><TR><TD CLASS="quote">Okay, so installing the VAFC, can that open the secondary butterflies eearly so your all the way open at say 4k? i think thats what i ment to ask lol</TD></TR></TABLE>

even if you could, that's a bad idea

the low engagement and secondary's work together to make a smooth torque curve

 

Wow, there is a lot of learning going on here.

 

yea changing Vtec crossover points on an otherwise stock motor is not good. its there for a reason.

only a dyno tune will tell you whens best to have vtec engage... that way you can do it the right way, Selonoid AND fuel/ign maps together.

i hate how some ppl will swap a vtec motor in their cars and run a non-vtec ecu and run the selonoid to an MSD RPM activated switch... i actually know a rasta (&lt;him being a rastafarian doesnt mean anything lol hes a friend) that has his vtec hooked up to the horn button on his d16y8...while running a d16y7 non-vtec ecu... stupid...just stupid.

he wont listen to me...till i put the correct **** in his car and it ran 100% better.

ghetto faBuliouS M@DD vtAc y00

correct ecu/wiring/fuel-ign maps

 

if you wanna use a vtec controller on a gsr with i/h/e you can
its better to have vtec kick in around 5500
and you can do that with a vafc
wtec takes away bottom end torque
i like it better at 5500

 

well VAFCs can also be used to tune fuel maps. Usually, stock cars dont run at their optimal AF ratio for performance. Usually they run a BIT rich. Even if you got an intake or something, you could use the VAFC to get the most out of it. But lol you'd have to go on a dyno to tune it ...making it very cost in-effective.

Edit: But i think most hondas run a bit lean after VTEC dont they? Not sure on this one. I know the earlier S2000s run rich everywhere...not sure about the other VTEC motors.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by immrtaltchnq &raquo;</TD></TR><TR><TD CLASS="quote">if you wanna use a vtec controller on a gsr with i/h/e you can
its better to have vtec kick in around 5500
and you can do that with a vafc
wtec takes away bottom end torque
i like it better at 5500</TD></TR></TABLE>

lol. bottom end torque.