As most you might be aware, the car won't vtec at stationary regardless of rpm with the stock ecu. The AEM EMS adopts the same approach and won't engage vtec unless VSS>0.

I like to launch my car at 7-8krpm with VTEC. I've posted a thread on the aem forum to see if there is any simple software change. However I've not gain any good result so far. Has anyone done this manually ie wire a switch to activate the vtec solenoid?

 

Should be straightforward to do it with a switch to the solenoid. I expect it's just 12V to the solenoid.

That said, with the EMS I would think you could set the minimum speed requirement to 0. It's only the ECU that sets the parameters.

 

switched 12V power to the solenoid will engage it, but you still need enough oil pressure and volume for it to function. 57psi of pressure is the minimum. The S2k's I've seen with Oil pressure gauges installed run 20-25psi at idle, and 75-125psi above 4k.

As long as you don't engage it at idle, and watch the oil pressure it will work.

 

^ both of you are right
you can wire a 12v+ to the vtec or pin 12 of the ecu 25P plug

alternatively you can wire a switch to the aem ems and programe the ems to activate vtec when this switch is grounded.

Has anyone actually try any of these methods yet?

 

On a old Civic EX race car we used to run, one weekend we had a problem with the VTEC solenoid cutting out. Direct 12v power did the trick, until we could replace the unit back at the shop. Car ran like crap and had no power below about 800rpm of the orginal VTEC point. Too forever to rev up too. While racing it was not much of an issue but getting going and around the paddock really sucked.

 

Can anyone decribe how VTEC works?

I have the OEM mech manual, and i've seen very little on the topic.

 

The camshafts have two different profiles (lobe sizes) to open the valves.

When in VTEC, oil psi locks a third middle rocker to the outer rockers, and operates the valves on the bigger cam lobe.

 

Explanation on VTEC..the first link is old but still relevant

http://asia.vtec.net/spfeature/vtecimpl/vtec1.html

http://world.honda.com/HDTV/news/200...05a/index.html

 

hi all
so if I had the solenoid activated manually the vtec would cut in at about 4000 rpm
anyone tried this and noticed a performance improvement at lower rpm?
cheers
paul

 

Did ya even read my post?

No,it will be on all the time, and no, power will suck below 4200!