Obviously, if your VTEC isnt working there is something wrong, but what if you were to disengage the input to your solenoid or something so that your VTEC would not kick in no matter what?
Like if there were a roadtrip that you know you would be traveling 85 or so, with the tach well into the vtec range. Would disenguaging the vtech give you better milage? or possibly worse, and put wear on your valve train?
Actually, make it like a switch that you can turn on and off the vtec function. not to turn it on or off full time, but to allow for normal, and non vtec operation depending on if you wanted the option of performance or efficiency.

shoot holes in my idea, I hope to hear from all those with their vtec not working on how the engine acts without it.

Cheers!
sohc


[Modified by SOHCMAN, 1:53 AM 12/18/2002]

 

Not sure if the fuel map would know if VTEC is on or off. If the ecu thinks your in vtec when youre not its going to pour fuel in that you dont need.

 

i personally never drove a VTEC engine, so i don't know, but knowing somethings about them i might dare to say, that if you are on a highway and your gas pedal is like 1/3 or 1/4 down, vtec shouldn't kick in, remember honda made this car to be as effective as they could (especially on gas), so i don't know, it might be that way already or i might get flame for this, either way i'll learn something new

EDIT: at what RPMs you are driving at 85 MPH?


[Modified by GZERO, 9:12 PM 12/17/2002]

 

not good when it's not working but shouldn't hurt it, your vtec isn't working when your car is in cold start, so it should just feel like a pig, the car should regulate it's A/F ratio accordingly when vtec isn't working. It might run a bit rich, but why would you want to do that, if you're worry about fuel economy, just keep your foot off the gas, much more efficient than putting a switch in to kill vtec


[Modified by v6illusion, 2:43 AM 12/18/2002]

 

my vtec is dead on my h22 and i am getting crap gas milage. dude it aint worth it to run without it.. its there for a reason. or you would of stuck with the lx model

 

plus vtec is known for providing better gas mileage during the higher rpm.

 

thats must be why i got like 170 miles to the full tank

 

Not many VTEC cars should be in VTEC at 85 MPH.

I know for a fact an Accord won't be...
ITR... nope.
Civic Si.... hell no.
Prelude....naw.
GSR... you wish.

So what is this argument about?

 

Does that means i was right?

 

you guys are having a hard time figuring out when vtec kicks in like i am. i have seen this item on ebay before but never paid any mind to it untill know . it's a kit not sure whats in the kit but it' suppost to be a lite in your gaugue cluster that comes on when your vcet kicks in . have you guys seen or heard of what i'm mentioning.

 

First of all I don't think thats the question he wants answered but... Yeah, basically all you're doing is splicing a light bulb or LED into the line that goes from the ECU to the VTEC Solenoid. When the ECU sends power to the solenoid it also lights up the bulb. You can do this yourself without buying the kit off e-bay.

 

some people will pay money for anything.......... it wouldn't matter when high cam engaged because the electric signal always travels to the solenoid, so it light regardless of wether it crossovered or not

VTEC is a system installed on cars for better fuel mileage, now I am not sure but it would seem that if you just disconnect the solenoid the ECU would still inject more fuel and air into the throttle body causing the car to run richer and much more inefficent

 

ok, disregard what I had previously said, guess I was wrong. I was going off what someone else had told me, I don't have one so I wouldn't know.

 

What if you ran the Vtec head off a non vtec ECU? It may dump in less fuel yes? (Just a dumb idea, sorry)
I didn think about how it would probably not be in Vtec if the car was going for better milage (good ol Honda) I was assuming that if you were above the 3000rpm limit(that is the enguagement point right?) that it would kick in, even on the highway(not well thought out)
When going 85 in my LX Im around 3250rpm in 5th gear...


AN odd question: is there any way to put roller rockers on a non-vtec head? After market, probably not, maybe oem from a vtec head? hmmmmm, doubtfull?

thanks for all the replies!
cheers
sohc

 

I believe VTEC enguages at 5,500rpm.

 

I got the VTEC indicator in my h22 accord.
It was really cheap and really easy. It took me a
half hour to install and you can mount the light anywhere you
want

 

(I believe VTEC enguages at 5,500rpm.)

Um, is this right? If so then whats the deal with having no vtec??? How often do daily drivers go into that rpm range??? and if vtec was invented to gove you better efficiency, who is going for efficiency at 5,500rpm???
What is the stock kick in rpm????

cheers
sohc

 

You are probably in limp/safe mode thats why and for protection it dumps lots of fuel. Unless you can rev it out to 7500. I dont know specifically which vtec cel codes will trigger limp mode. I know for sure that 21, or the vtec oil pressure sensor will cause it. The lack vtec itself so to speak is not why you are getting bad gas mileage. Its because the ECU thinks something is wrong and to prevent you from damaging the motor it will run very very rich.

Switching to a high cam lobe and going to WOT with variable valve timing and electronic lift control to aid in high rpm breathing is for 1 thing, horsepower, not economy. The high rpm breathing is not the only aspect to the vtec system though. When the motor is off the high cam the valve timing is optimized to provide good fuel economy. Jekyl and Hyde.

 

I am quite sure on an F22B the VTEC engages REAL LOW. This has been an argument many times. Sure, on an F22B it suddenly gets real loud and there may be a perceived power surge at 5,500 RPM, but the Helms manual and a VAFC will report the VTEC crossover at below 3,000 RPM.
You won't destroy your motor running on the lo-cam all day, but top end power falls off like ****.

 

(When the motor is off the high cam the valve timing is optimized to provide good fuel economy. Jekyl and Hyde. )

I was under the impression that the only variable valve timeing was on the new Vtec-I's and that the B series Vtec was simply a mechanical/hydraulic valve train that switches over for more flow at high rpm... Correct me if I am wrong please.

So the determination is: its fine to run w/o vtec so long as you dont care about the high end power(becasue it would be non existant with one of the valves hardly opening)

Question: so when DOES vtec enguage on a F series??

interesting though: Swapping the head of a B2 with a B1 was determined not cost effective earlier by this forum. How is a 15HP bolt on (well, pretty much bolt on) not cost effective ? especially when you can spend 1k-1.5K on I/H/E and end up with 4-5HP ?

cheers
sohc

 

vtec is a good thing.

if you disable it, you will be a sloth, trust me, i've had it happen when we forgot to hook up a portion of my engine harness, your overall exceleration will suffer, and your top end won't exist, the f22b1 changes over to vtec @ 2300rpm, i'm currently battling tuning issues with my v-afc about this.

v-tec points are different from honda to honda, depends on the motor in question, and the ecu program it runs. the type r's and higher strung 1.8's will changeover higher up in the rpm band, the accords were mean't to be commuter cars, and there ecu's vtec was programmed accordingly. type r's, si's, gsrs, they all are 1.8's, can outrev are 2.2's, and were assigned different vtec points accordingly.

don't run w/ out vtec, if you've got it, use it.

 

Well .. with my VAFC my vtec engages (or at least the light comes on) at 3100 rpm So cruising at exactly 81 mph .. bumps me into vtec mode hehe. I am still getting rather good gas mileage .. around 390-410.

 

From what I heard, the more high horsepower you get into, the more VTEC is useless. Not sure why though.

 

q: why do drag racers like it?

a: notice how vtec gives a suddun surge i power, that's probally one reason since if your trapping in the 8's then a sudden surge could break the tires loose and crash you. also, if you drag racing pro, do you really think fuel efficency's a concearn?

 

Many mega all-motor DRAG cars have to do away with VTEC... the added cam lobes and vavletrain components make for too much valvetrain weight.
VTEC valve duration and lift switching allows for good bottom and top end... the drag cars just want all super-high-RPM top end.