I was looking at the wire diagram the other day for the GSR and how the secondaries work from the ECU and I got an idea.....Would there be any gain from opening the secondaries at the point vtec is engauged? You could just run the wire for the vtec output on the VAFC to the seloniod for the secondaries. My car has ITR cams and AEM intake. Would having say 5100-5500 the cross over point for Vtec and secondaires work?

 

No point.

 

Just set vtec to engage with the secondaries. I think it's at 6500 rpms. you might lose mid-range power but the kick is fun.

 

I recently completed this very project... her is my post on it...

https://honda-tech.com/zerothread?id=688996

The stock fuel map and compression ratio of the motor require the secondaries to open no sooner than 5500rpms (or a loss of torque is noticed).

It is harder to wire than you think, because most diagrams... including the Helms!!! are wrong when they show how the IAB solenoid is controlled by the ecu...

The vtec control of the VAFC is done by providing batt. voltage at a specific time... this will not work with the IAB because it is constanly given a 12v. signal to hold it shut, then when 5750rpm comes the ecu cuts the GROUND off and it opens the valve. I used an MSD RPM switch that switches to ground and an infinitely adjustable RPM "pill"... tacked it into the wiring harness and cut the ecu out of the picture... NO CEL(mil) either!!!

Ive played with every setting 2k-7k, trying to retune the ecu with my VAFC2(and my butt) around 5500 is the sweet spot... and you dont have to slam gears as hard to keep the secondaries open during 1-2 shifting

NOW... The type R cams, which I have some I'm about to install , would benefit from possibly a 5k rpm opening because of the airflow required. With dyno tuning it could be set to exactly the best time for vtec to switch and the secondary runners to open for most torque/HP/MPG combo.

Or just lose the 1MPG and get a Skunk2

 

I could use a relay that would cut power to the selinoid to make it work....Now if I where to do that I am wondering if I am going to see a dip in power if I open the secondaries and engauge vtec at say 5200-5500. The way I am thinking is with a 5700 secondary cross over (stock) and vtec engauging at 5200 you have a little time where you have an increase in air flow demand and then the secondaries give it that demand. If they would both acure at the same time you would most likely get a dip in power correct?