Raise Vtec point to increase FE?

[MrChoi]

Originally Posted by monroe74

I know a simple switch can be used to defeat VTEC entirely, or turn it on and off manually. Other than that, I wonder what kind of control you're describing.

how do you do that? do i just remove the vtec solenoid wire?

[MrChoi]

Originally Posted by dkjones96

2500 rpm? Seriously? I guess it's because I've only dealt with newer engines but All the hondas I've dealt with go to VTEC way higher than that.

The 3.2 V6 is about 4500 and the S2000 and Civic Si engines are closer to 5750.

s2000 vtec kicks in at 6000 rpm just as monroe74 said the vtec system on VX and HX are totally different found on cars like the s2000.

[monroe74]

mki: "vtec controller YO"

Thanks, that's interesting.

"you have no idea how hard it is to keep this in lean burn"

How can you tell when lean-burn is happening? Are you judging by the way the engine feels, or are you using some kind of instrument? Just curious.

By the way, I like your avatar. Would you be willing to share a full-size version?

hatch: "I know people that have used a VAFC to move their VTEC engagement for road trips."

Right, it's just that I've never heard of anyone using a VAFC on a VX. Or are you saying you know people who did that?

mrchoi: "do i just remove the vtec solenoid wire?"

I think that's all you would need to do. But I'm not an expert, and I haven't tried it.

I wonder if the ECU would notice, and give you a CEL. Other than that, I figure nothing bad would happen.

I haven't been motivated to try this, because when I'm interested in economy I just stay under 2500 rpm (sort of like what theclencher said). For most of my driving, that's very doable.

[EH3]

keep it stock. VTEC-E on the VX/HX is not for power.

the ECU will throw a VTEC solenoid code if you disconnect the harness plug

honda designed it to engage at 2500rpm knowing that 90% of US highway speeds are over that rpm. i highly doubt your FE will suffer

[monroe74]

"honda designed it to engage at 2500rpm knowing that 90% of US highway speeds are over that rpm"

Good point. On my VX 2500 rpm is about 69 mph. These days I'm not usually going that fast. And that's without taking into account the 2% speedometer error due to the larger-than-stock tires.

[MrChoi]

now do you know when lean burn turns off? even at 75mph scan gauge said the car was in lean burn.

[monroe74]

"even at 75mph scan gauge said the car was in lean burn"

That statement confuses me, because I was under the impression that the SG does not recognize lean burn. See here.

[Danronian]

Originally Posted by EH3

keep it stock. VTEC-E on the VX/HX is not for power.

the ECU will throw a VTEC solenoid code if you disconnect the harness plug

honda designed it to engage at 2500rpm knowing that 90% of US highway speeds are over that rpm. i highly doubt your FE will suffer

I don't agree with the comment about vtec-e not being for power. If you've driven a VX where vtec isn't working, and then drive the same one with vtec, yeah, it's there for power-on-demand. It's needed for passing and merging.

To the OP, if you want to see how the car will be with no vtec, cause the check engine light to go on, and the car will stay out of vtec in order to protect itself. That being said, if you have a CEL on, the engine will run richer than normally in order to stay safe.

Vtec (and vtec-e) does not always engage at a certain RPM unless the throttle position is at a certain percentage. So if you accelerate very slowly but still go over 69 mph, you will stay out of vtec.

To the OP:

Don't mess with the vtec-e engagement point unless you are willing to tune the fuel maps. There is no off/on switch that can make the vtec-e motors to get better mileage. There is a lot of research into the heads of these and the tuning so that they get the amazing mileage they do. If you plan on puting that much work into it, to get a few more MPG, do it. But be ready to do a lot of work and pay a tuner and a car-dyno a lot of money to do so.

[MrChoi]

http://www.insightcentral.net/commun...an+burn#p67235

maybe scan gauge can monitor lean burn only on the insights? not too sure anymore.

[monroe74]

Interesting thread, thanks for pointing that out. I don't know the answer.