What damage could this cause for someone actuating the vtec solenoid at any given rpm?

 

Bump: Anyone?

 

If vtec's activated too early, you can lose power.

 

I guess you could. But your ecu changes it's fuel mapping with the apprpriate cam profile. Your button would not change the fuel mapping with crossover. It could only be detrimental. Well, at least that's what I think.

 

wouldn't be the same concept as wiring vtec to an rpm switch like msd? if so, it's not detremental, just ghetto; it shoudl work i guess. there probably won't be any benefit, liek someone already said if vtec kicks in early you'll lose power, if too late it will be an abrupt change.

 

I agree. It's basically ghetto because you are just specifying what the ECU would normally do. I'm not sure how a VTEC controller works, but you are just changing the factory settings that the ECU provides. In terms of actuation, not mapping.

 

yes, but your ecu changes fuel mapping at vtec crossover, so whether you've got an rpm switch, or a button, the ecu will still switch fuel at whatever rpm it originally crosses over. When valve lift and duration increase, more fuel is going to need to flow. The ECU accounts for this at crossover.
It's definately ghetto. And whatever the case may be, not a good idea.

 

its piontless. honda ecu's are a lot more complicated and advanced than some of you may think. the ecu actually has several vtec crossover pionts and several fuel maps after crossover, depending on tps position and rpm. they also have several fuel maps depending on altitude. your ecu actually has a little altimeter in it. so it would be retarded to put vtec on a switch or button. you would basically just lose power.

 

no point. why would you want to do this for??? you will have no low end power if vtec engages too early. also, the oil temp needs to be warm for vtec to work properly.

 

VTEC depends on oil pressure to function. You can't just click a button at any RPM and expect it to engage.

 

engagin vtec at a lower rpm could make you lose power and may damage your engine due to fuel. wtih the VAFC you can fine tune your fuel wtih the vtec engagement unlike a factory ECU where you cant just change the fule mapping.