Vtec control question ?

[elderc]

I need to switch a 12v relay "on" and "off" based on rpms say "on" at 5,550 - "off" at 7,500 to control my vics system on my intake manifold. Can the Vtec
settings be used to do this (if so how) or would it be eaiser just to buy a rpm switch ?
Thanks in advance

[Dzaster]

It can be used, but it has to be rpm vs greddy MAP, stock MAP, TPS, etc.

To do this check my first post in THIS (http://www.diytuning.com/forums/showthread.php?t=103) thread. Mind you, I use it for methanol injection, but you could use it for most anything that is dependent upon those parameters previously mentioned.

It most likely can be used if you have an intake manifold with secondary runners that uses a vacuum switching valve(solenoid) to regulater airflow to an actuator. So basically you may be able to use as a boost controller. Actually a better boost controller as well. A friend, GT_REVVA, over at the other forum I frequent suggested that you could use the sub-injector map to control a solenoid for a boost controller.:eek:

[elderc]

Thanks D,
Yes, I'am trying to control a second set of runners on the intake. As of now the stock ecu has control, heres how it works : when you start the car
vac. is applied to a accuator (through a solinod) which closes the butterfly valves and they stay closed untill 5,300 rpm at which time voltage is cut (to the solinod) and the valves open up. The issue I'am having is under boost the vac. used to hold the valves closed is lost so the butterfly valves open to early like 3,000 rpm. What I want to do is install a 12v mechanical accuator switched by rpms only ( not based on vac.) this would give me better control on the change over..........looks like the emb can't do this based on rpms only ?

[Accord2nrz]

Its possible to do it based on rpm's only but you will have to figure out what voltage is coming from your ignition to determine how much voltage = x amount of rpms. I wouldnt imagine it would be too difficult from there on.

Anyone else beginning to think the Greddy was off in lala land when they engineered this thing? it's great tool and i love it to death but sheese. We should modify the core electronics of this thing and produce another emb blue that does all this. wait hmm.... idea brewing lol. :p

[elderc]

Ok, did some data logging using third party software 4.65v (air flow in) is 5,294 rpm so I need a "on" signal starting at 4.65v and a switch "off" when the voltage drops below that. Can that be done ?:confused:

[Dzaster]

Yeah man, you can totally do that. Do you know if that solenoid is just open/close or does it pulse?

If its pulse type you can use the sub-injector map and totally set it up to pulse. It's a 12V negative pulse type signal though. But easily work if your solenoid pulses to regulate airflow.

[elderc]

The solenoid is n/o 12v closes it (left pix). Its not used for metering its only used as a
"on and "off" source for vac. to hold a accuator closed for the valves in the intake runners untill 5,200 rpm. I guess the question is does the vtec wire send out a 12v supply so I can switch a relay (from another 12v supply) to control the solenoid ?
Thanks

[Dzaster]

The VTEC output voltage is like 5-6 volts. However, it is apparently enough to reliably trigger a relay--the ones used in auto applications.

And it would definitely work for that!

[elderc]

Thanks !:D

[Dzaster]

Keep us posted on this. Reason being, our cars tercel/paseo/starlet have a similar manifold and I'm pretty sure it works that same. I know kennymp3 has one, missing some hardware though.