Disable the VTEC Solenoid Valve

[Guest xracr]

Does anyone have any experience energizing the VTEC solenoid valve so that the engine is in full time 4 valve mode ?

[Veefer800Canuck]

Aww c'mon, no guts no glory!

Don't let fear and good judgement hold you back!!!

[Veefer800Canuck]

Aww c'mon, no guts no glory!

Don't let fear and good judgement hold you back!!!

[Ryanme17]

Although I am one of the people who think that because the bike was designed to run with 2 valves that it just wouldn't be right on four in low RPM's don't let that stop you.

With a PCIII and a good tuning center you can adjust your fueling to run on all 4 valves. I don't think timing would need to be adjusted, and with proper fueling there's no reason you can't run on all four valves all the time.

As long as you aren't running lean, I also see no reason why this would hurt your engine.

[Guest]

Sure, suddenly now that everyone convinced me not to do it, its like 'Go for it!'

I don't have a Power Commander, so I can't adjust anything to make this work. But surely someone out there has the tools and expendable V4 engine to try? Think of the cool custom map you'd have for the ultimate Anti-VTEC mod! Imagine if it actually worked... the fame and fortune...

Derek

[ericlw]

im 36,000 miles on my 02 and some hard accelerations i have NEVER been able to make my rear wheel chirp. if you just roll through the transition its cant be that bad. if you move up to it and then back off maybe?seems strange its really that bad.

[Guest]

im 36,000 miles on my 02 and some hard accelerations i have NEVER been able to make my rear wheel chirp. if you just roll through the transition its cant be that bad. if you move up to it and then back off maybe?seems strange its really that bad.

The tire chirped in maybe the 2nd left hander I took. If you roll through that transition hard on the throttle, its rather abrupt. I didn't try to do it, I was just riding like I normally ride my past 7 bikes. Not saying its the end of the world or anything. But it definitely took me by surprise.

In fact, I was sure that in the 8 years this bike was made, someone had already tried disabling VTEC and I was looking for the results. There must be some V4 VTEC engine guru out there that can calm the fears of low oil pressure and those pins. Fueling can be taken care of with a good, careful tuner. I do wonder about timing a little bit... again, where is the guru?

Derek

[Veefer800Canuck]

I've been in the Vfr online community since the halcyon days of the old Vfr@cs.wisc.edu mailing list. And on Vfrd since the old Delphi freehosting site etc, and I remember exactly ONE dude who actually posted up that he jumpered out the 12v for the vtec.

He said it ran fine, didn't do any empirical testing or tuning, his bike didn't blow up, and he put it back to stock shortly thereafter for fear of wrecking something, even though he had no proof or even a slight indication that damage was imminent or even plausible.

I have not seen one single before/after Dyno chart, a/f ratio readout or long term durability test EVER and I've been snorting, shooting, eating and drinking all things VFR on the web since before the first 800 Vfr came out in 1998.

Not trying to come off as Mr Fancy-Leathers, i'm just saying that if someone had already done a proper anti-vtec mod, tested and tuned for months and thousands of miles, plus backed it up with Dyno charts and fuel ratios, I'm certain it would be a HUGE sticky right here on VFRd in the modifications section.

Someone please take up this cross and do it up right, K? Pretty please?

[dutchinterceptor]

Seems like we get one of these threads every few months.

April's Disable VTEC Thread

[Auspanglish]

I've posted up on this before.

It can be done.

It has been done.

You can throw in a switch to turn VTEC on and off if you like.

You can even use a dimmer-style dial to adjust at what RPM you want VTEC to be activated at... maybe you'd prefer it to kick in at 4500RPM (get off the mark earlier)... or 7400RPM (better fuel economy when slabbing). Locate the dial down near the idle adjust screw maybe??

The only problem the engineers (one mechanical the other electro-mechanical) I know over here in Spain that have done it say that could arise is at low RPM, when the oil pressure is low... and there are things you can do about that but it wold mean major open-heart surgery. One bike made some fairly chunky noises below 3000 RPM due to lack of oil pressure... but these guys seemed to think that anywhere from there up, wouldn't be a problem, so you just make a chipset to fool the solenoid that you're complying with two requirements: 65ºC coolant temp and 6800RPM (2002-2005 year models). There's also a need for oil pressure to activate the 4 inyectors... 5kg/cm2 +/-1kg. This is why below 3000RPM you can get some clunking going on. It's not the same when the oil is cold as when it's hot or not flowing as quickly etc..

I have copied a lot of the musings and thought processes behind one of these engineer's experiment in Word... but it's in Spanish and I couldn't be arsed to translate it.

Safe to say this one guy still has this system on his 2002 VTEC 5 years later and no problem.

I should mention he also programmed in for the system to "preload" the system just a few hundreths of a second before fully entering VTEC, to give a litle squirt of oil pressure and get the whole system ready, in case it's a little low on oil pressure.

Fuel economy was not affected. Torque seemed to increase (seat of pants appreciation). One should resynchronize the starter valves with a carbtune once having performed an operation like this.

According to this guy, he seemed to find the transition much smoother around the 5000RPM mark.

He used a PIC 16F628

[vfr_steve]

I've posted up on this before.

It can be done.

It has been done.

You can throw in a switch to turn VTEC on and off if you like.

You can even use a dimmer-style dial to adjust at what RPM you want VTEC to be activated at... maybe you'd prefer it to kick in at 4500RPM (get off the mark earlier)... or 7400RPM (better fuel economy when slabbing). Locate the dial down near the idle adjust screw maybe??

The only problem the engineers (one mechanical the other electro-mechanical) I know over here in Spain that have done it say that could arise is at low RPM, when the oil pressure is low... and there are things you can do about that but it wold mean major open-heart surgery. One bike made some fairly chunky noises below 3000 RPM due to lack of oil pressure... but these guys seemed to think that anywhere from there up, wouldn't be a problem, so you just make a chipset to fool the solenoid that you're complying with two requirements: 65ºC coolant temp and 6800RPM (2002-2005 year models). There's also a need for oil pressure to activate the 4 inyectors... 5kg/cm2 +/-1kg. This is why below 3000RPM you can get some clunking going on. It's not the same when the oil is cold as when it's hot or not flowing as quickly etc..

I have copied a lot of the musings and thought processes behind one of these engineer's experiment in Word... but it's in Spanish and I couldn't be arsed to translate it.

Safe to say this one guy still has this system on his 2002 VTEC 5 years later and no problem.

I should mention he also programmed in for the system to "preload" the system just a few hundreths of a second before fully entering VTEC, to give a litle squirt of oil pressure and get the whole system ready, in case it's a little low on oil pressure.

Fuel economy was not affected. Torque seemed to increase (seat of pants appreciation). One should resynchronize the starter valves with a carbtune once having performed an operation like this.

According to this guy, he seemed to find the transition much smoother around the 5000RPM mark.

He used a PIC 16F628

That's damn impressive stuff - why the hell doesn't he work for Honda?

Might I just add in addition to my post the numerous test rides on 06+ VTEC's I have had are MUCH improved and the ones to go for IMO ;)

[Auspanglish]

I've posted up on this before.

It can be done.

It has been done.

You can throw in a switch to turn VTEC on and off if you like.

You can even use a dimmer-style dial to adjust at what RPM you want VTEC to be activated at... maybe you'd prefer it to kick in at 4500RPM (get off the mark earlier)... or 7400RPM (better fuel economy when slabbing). Locate the dial down near the idle adjust screw maybe??

The only problem the engineers (one mechanical the other electro-mechanical) I know over here in Spain that have done it say that could arise is at low RPM, when the oil pressure is low... and there are things you can do about that but it wold mean major open-heart surgery. One bike made some fairly chunky noises below 3000 RPM due to lack of oil pressure... but these guys seemed to think that anywhere from there up, wouldn't be a problem, so you just make a chipset to fool the solenoid that you're complying with two requirements: 65ºC coolant temp and 6800RPM (2002-2005 year models). There's also a need for oil pressure to activate the 4 inyectors... 5kg/cm2 +/-1kg. This is why below 3000RPM you can get some clunking going on. It's not the same when the oil is cold as when it's hot or not flowing as quickly etc..

I have copied a lot of the musings and thought processes behind one of these engineer's experiment in Word... but it's in Spanish and I couldn't be arsed to translate it.

Safe to say this one guy still has this system on his 2002 VTEC 5 years later and no problem.

I should mention he also programmed in for the system to "preload" the system just a few hundreths of a second before fully entering VTEC, to give a litle squirt of oil pressure and get the whole system ready, in case it's a little low on oil pressure.

Fuel economy was not affected. Torque seemed to increase (seat of pants appreciation). One should resynchronize the starter valves with a carbtune once having performed an operation like this.

According to this guy, he seemed to find the transition much smoother around the 5000RPM mark.

He used a PIC 16F628

That's damn impressive stuff - why the hell doesn't he work for Honda?

Might I just add in addition to my post the numerous test rides on 06+ VTEC's I have had are MUCH improved and the ones to go for IMO ;)

he works for a lot of large industrial applications and dealswith these systems all day everyday.

[V4 Rosso]

Wasn't there a post about this not too long ago that included a dyno run with the change in place or am I losing my mind?

Yes, but more work was involved than just permanently activating a solenoid:

[gswanson]

I got my 07 new this last Christmas and it now has over 6000 miles on it. I don't have any problems with the VTEC engagement, I can feel it but it is not abrupt and never has been. It reminds me of my younger days riding two-stroke dirt bikes and the kick in the pants you got when the motor "came up on the pipe". I have more annoyances witht the lean fuel map around 5000 RPM, my normal cruise range, than the VTEC transition. You just got your bike, ride it for several thousand miles learning it's traits before you decide that Honda got it wrong.

[Skids]

Its a Love Hate thing really. Some like it some don't. I love my VTEC transition personally... but like the guy said above. You'd probably come out better to sell your 6th and get a 5th. Might even make a buck or two depending on the deal. Less headache also.

First of all - 5th gen is better in what way in regards to VTEC? I guess it doesn't have VTEC? Second, no way! I love my RWB 07!

I could deal with weaker low end, assuming it is decent. I don't think it has any low end the way it is now anyway. Feels like a 600 without the top end.

I have both a 5th and 6th gen, so I have a valid comparison but it is just my opinion in the end. I far prefer the engine on the Fi...perhaps because it's just run-in (100k+ miles) whereas my Vtec has only done 22k so is still a little tight. There is no doubt that the Vtec chassis (including ABS) is better though. It turns in quicker and somehow manages to have better headlights too. I'm not convinced the build quality is as good as the Fi though. The Vtec system was a mistake. the Fi engine should have been developed more to meet emission regs rather than the backwards engineering step that the Vtec was. Shame really.

Can one of you guys please fit an Fi engine into a Vtec (ABS) chassis, then super-charge it. Then ship it over here and sell it to me in $. Thanks.

As to the OP...a friend of mine over here had his Vtec disabled, though I don't think it was as simple as you suggest in your post. Apparantly it rode well, but drank fuel like drinky-fuelly thing. He converted it back shortly thereafter.

[Rice]

So, there is one guy who has disabled his VTEC with positive results, right?

I think that the reason why this mod has never taken off is because VTEC has a way of growing on you.

When I first got my 02, I was pretty much in the same boat as Derek here. I hated the way it behaved - Not so much that it jerked the bike, but the fact that it was inconsistent - I never knew what to expect.

The fact that many people had no such issues didn't help the situation either - That meant that my bike was defective somehow.

All of the above did nothing to make me like VTEC and I did my share of complaining on here at the time.

Now, that I have an 06, I can honestly say that I love my VTEC. I actually enjoy the transition and look forward to it as part of the fun that comes with the package.

Yep. It has grown on me, as is probably the case with most owners of VTEC.

So, to Derek and to all new owners - Give it time. You'll learn to appreciate and enjoy it.

[Guest]

So, there is one guy who has disabled his VTEC with positive results, right?

I think that the reason why this mod has never taken off is because VTEC has a way of growing on you.

When I first got my 02, I was pretty much in the same boat as Derek here. I hated the way it behaved - Not so much that it jerked the bike, but the fact that it was inconsistent - I never knew what to expect.

The fact that many people had no such issues didn't help the situation either - That meant that my bike was defective somehow.

All of the above did nothing to make me like VTEC and I did my share of complaining on here at the time.

Now, that I have an 06, I can honestly say that I love my VTEC. I actually enjoy the transition and look forward to it as part of the fun that comes with the package.

Yep. It has grown on me, as is probably the case with most owners of VTEC.

So, to Derek and to all new owners - Give it time. You'll learn to appreciate and enjoy it.

Hey Rice! I rode the bike today a little more relaxed, and yeah, the VTEC wasn't really noticeable, other than the change in exhaust note. There are occasions hard on the throttle that you'll feel it jerk. I guess on paper this VTEC system is good, but in the real world, I don't see any positive effect at all. I've had (1) 525, (2) 600s, (1) 750, and (2) 1000s. None had VTEC and all seemed fine. VTEC is a solution looking for a problem.

Anyway, it certainly doesn't bother me to the point where I would sell it. But if there was an *easy* way to get rid of it, that would be great. Not looking for any 'power gains' or 'torque gains' like some suggest, I just think its unnecessary and causes more harm than good. But again, the bike overall is getting better to me.

Derek

[Ryanme17]

I only notice my VTEC transition when the engine is about 165 degrees. Once it warms up the abrupt transition goes away.

[carlitos92]

So, there is one guy who has disabled his VTEC with positive results, right?

I think that the reason why this mod has never taken off is because VTEC has a way of growing on you.

When I first got my 02, I was pretty much in the same boat as Derek here. I hated the way it behaved - Not so much that it jerked the bike, but the fact that it was inconsistent - I never knew what to expect.

The fact that many people had no such issues didn't help the situation either - That meant that my bike was defective somehow.

All of the above did nothing to make me like VTEC and I did my share of complaining on here at the time.

Now, that I have an 06, I can honestly say that I love my VTEC. I actually enjoy the transition and look forward to it as part of the fun that comes with the package.

Yep. It has grown on me, as is probably the case with most owners of VTEC.

So, to Derek and to all new owners - Give it time. You'll learn to appreciate and enjoy it.

+1,000

I wish I could have double the VTEC hit; I think it's fun. And sometimes, funny. It always takes me back to the first time I ever rode a VFR. The first time it went to 16 valves it literally scared me. Later on that short test ride I remember it hitting the VTEC transition and abruptly going "GRRRONNNKKKK" so loud pedestrians looked up and gave me a "WTF was that" look.

[Guest]

I wish I could have double the VTEC hit; I think it's fun. And sometimes, funny.

A VTEC hit is fun, but it is downright dangerous in a turn. So I think you wouldn't really want double the hit. This is the same reason turbos don't exist on bikes anymore. The sudden turbo power surge can at the least make you run wide and at worse make you highside. And I have highsided before - you don't want that.

Derek

[Guest]

I only notice my VTEC transition when the engine is about 165 degrees. Once it warms up the abrupt transition goes away.

From my VERY limited experience, the transition is going to be abrupt if you go WOT under 6800 RPMs. Under anything other than WOT, it is not that noticeable to me. The only reason I brought this up is that the first hit I took was in a turn, where the tire chirped and stepped a little sideways. I mean it was very little, but imagine being at max lean, or on a wet road. Why is that good? I don't get it.

Derek

[luckylendy]

Does anyone have any experience energizing the VTEC solenoid valve so that the engine is in full time 4 valve mode ?

I have no experience with that, but I was amazed at the difference the Power Commander 3 made to my stock bike with the base fuel map that came with the PC3. I found myself blowing right through the VTEC transition without even noticing it. I didn't realize then that I had unintentionally conditioned myself to short shift a bit, avoiding the previous lurch associated with VTEC. Now it's smooth sailing.

[Infidel]

http://www.vfrdiscussion.com/forum/index.php/topic/67697-disabling-vtec-permanently/

Let's pick one....

[Veefer800Canuck]

Search is your friend. Many many topics on that subject.

[carlitos92]

I wish I could have double the VTEC hit; I think it's fun. And sometimes, funny.

A VTEC hit is fun, but it is downright dangerous in a turn. So I think you wouldn't really want double the hit. This is the same reason turbos don't exist on bikes anymore. The sudden turbo power surge can at the least make you run wide and at worse make you highside. And I have highsided before - you don't want that.

Derek

As long as it always happens at the same RPM and you are familiar with the bike, it's a non-issue.

The bold part of that statement is important, and you will get there with your bike eventually.

As for turbos on bikes, they weren't done very well. I have had several OEM turbo cars made from 2000-up, and there is nothing surprising in the least about when they come on boost. In fact, in my daily driver, I know when to ease up on the gas to keep power output somewhat linear and respectable.

[Guest]

As long as it always happens at the same RPM and you are familiar with the bike, it's a non-issue.

The bold part of that statement is important, and you will get there with your bike eventually.

As for turbos on bikes, they weren't done very well. I have had several OEM turbo cars made from 2000-up, and there is nothing surprising in the least about when they come on boost. In fact, in my daily driver, I know when to ease up on the gas to keep power output somewhat linear and respectable.

Riding around a problem and altering what you would do (on any other bike) in a turn seems odd to me. Especially when I see no measurable advantages in VTEC. I enter turns above 7000RPM now if I have any intentions of doing so aggressively. You can argue that its the right thing to do anyway on any bike (especially on a track). But not everyone rides like that, and if you are mid turn and decide to wick up the throttle a bit, you may end up high sided.

As for the turbo car, you are altering how you drive to manage the turbo, but at least there is a huge advantage to that turbo. VTEC kicks in and seems to add little, other than a jolt to rear grip.