I have made a switch to turn my 3stage vtecs on with the flick of a switch, in a race will it harm my engine or slow me down if i flick it on at say 3000 and leave it on through out the race , im talking about the performance soliod, when should i turn the vtec e on safely , does it harm my car to have the vtec e always on , should both vtec solidos be engaged at the same time?

In general I would tend to think it's not a good idea to have VTEC engage at low rpm's. the normal timing should be good enough for the low end, because the VTEC is not designed to improve torque (off the line accel), but to improve the upper power curve.

I have made a switch to turn my 3stage vtecs on with the flick of a switch, in a race will it harm my engine or slow me down if i flick it on at say 3000 and leave it on through out the race , im talking about the performance soliod, when should i turn the vtec e on safely , does it harm my car to have the vtec e always on , should both vtec solidos be engaged at the same time?



Well vtec as a system doesn't go off and on as I hope you know, its a system to switch cam profiles.


At low rpm you want a low lift cam and a high lift cam at high rpm. So trust honda engineers and let the high lift can activate at high rpm where it works best. If high lift cams worked best at low rpm too, honda would not had to invent vtec and would've left just one high lift cam profile for the entire rev range.

^^^ werd.

well with the right tunning you can replace ur low cams with just another set of high lift cams and be running lift all the time
it's referred to as the "VTEC-less engine" i has horrible low end but the top end is crazy!!!!!
plus you have a very deep buzzng noise so loud you ownt be able to hear yourself think inside the car :eek7:

Actually the highlift profile is beneficial on the low end too. I used a chipped Skunk2 ECU with the VTEC cross at like 1500. There was a difference in low end power.

And they created VTEC to get the high range rush, while having economy on the bottom end all on the same engine. What I mean is, if the B16A, or even D16Z/Y had ONLY the VTEC profiles, then they'd have shit for economy, emissions, and idle. It's less to do with activating it where it works best, and more to do with drivability.

Actually the highlift profile is beneficial on the low end too. I used a chipped Skunk2 ECU with the VTEC cross at like 1500. There was a difference in low end power.

And they created VTEC to get the high range rush, while having economy on the bottom end all on the same engine. What I mean is, if the B16A, or even D16Z/Y had ONLY the VTEC profiles, then they'd have shit for economy, emissions, and idle. It's less to do with activating it where it works best, and more to do with drivability.

do you have any actual data to prove that? Or is it just but dyno?

Anyway this article disagrees with you:

http://auto.howstuffworks.com/question229.htm

For maximum engine performance at low engine speeds, the valves need to open and close differently than they do at higher engine speeds. If you put in a good low-speed camshaft, it hurts the engine's performance at high speeds, and if you put in a good high-speed camshaft it hurts the engine's performance at low speeds

That's just generally. But yes, I am using the ass dyno...

If it was big enough for me to feel, then there's something to it. There are alot of things you can't feel when you mod, this I did.

A freinds' Skunk2 P28, further modded for very low VTEC

VS

My(eveyday) 92 B16A PR3, VTEC at 6000, reds at 8400.

Both in my Civic D16Z6...big low end difference. I can't prove it, so it's something that has to tried...

I've heard premature vtec activation will bog you.