ok good, I just thought of that last night as I was going over my own grounds on my VX and noticed that my trans-to-chassis ground is frayed and corroded. Since today is my last Duty Day for the school year, I can start working on my intermediate wiper How-to for the site along with rebuilding my spare VX motor, a brake job on the VX, and the re-grounding of the chassis. I also have two spots of rust left to repair and then my VX will be "factory fresh".

Rust... ah, I remember.... don't miss that though.

Do you happen to know how varying the calibration resistor would affect O2 operation? I cut it and put a 10K pot in the middle and things seem a little better at 10K than the default, which was 5.7K ohms. Gonna run and get a 20K and see what that does.... just playing around cause I can't seem to find a description of exactly what the resistor does, other than "calibrating" the O2.

Finding that a higher resistance value seems to lessen the lean burn agressiveness. Tonight driving home I varied the calibration resistance up to 60K ohms (default is 5.7k).... it was still missing slightly in lean burn.... but not very bad at all, at speed anyway. The voltage across D14,D18 was not as high.

also put in a brand new set of plugs tonight in the parts store parking lot... no noticeable positive change with them though.

Gonna get a 100K pot in the morning and try that.

hmm, I've never thought of changing the Calibration resistor. You're sailing uncharted waters at this point Lance. The only thing that I can think of is that th4e calibration resistor is part of the circuit for sending the O2 signal to the ECU, so in effect, you are altering the O2 signal that the ECU sees. But don't take my word for it as I haven't looked at the actual OEM controller circuit for the L1H1 in the P07 ECU, only the Ozzie controller circuit for the L1H1 which is different from the Honda one.

how much of a difference in mpg between CA models and 49 state? Im getting like 48mpg with my CA VX... 215k miles , hx wheels....

EPA est was 5 mpg greater in the 49 state... if I recall correctly it was 51 city 55 HWY ?.. something like that.

I am cosistently getting in the low 50's with a couple 54's and one 58.... before lean burn (which I am taking a break from for a bit)

OK, might have got this lean burn thing working... I tried a different O2 sensor and all of the voltages now seem consistant with what others have seen. I am also monitoring injector pulse rate and it seems like it is injecting about 10-15% less fuel at cruise now compared to the non-lean burn ECU (just antecdotal observation though).... I might have to fill up and make a MPG run after the US Open finishes :-)

Congrats Lance....Make sure to do a How-To to share with the world.

Yeah, I'll do a DIY after some of the MPG runs are in... just the info on which three 4-wire O2 sensor wires and which 4 harness wires to patch into will help others.

Lean burn is clearly working. I have a DMM hooked up to injector 1 measuring duty cycle. you can see (and feel) when it drops into lean burn.

Last tank was 62 mpg..... with A/C on for at least 1/2 of it and 10-15% city.

nice, and congrats! now get to that how-to, lol!

Best tank ever: 68 mpg.... 325 miles over one week's commute. Some A/C on even. Couldn't have done it w/o the Super Mid though.

You went from avg 50mpg to 68mpg?!?!
Do you have the shift light hooked up?
Thanks,
Gary

hey, been offline for a bit. No shift light but have driven one with a light. basically tells you to shift as soon as possible.... like 1600 rpms

lca13, please post a DIY on this process. I'm looking at a VX and just found out that its a CA FED VX. So far I know you need a non CA FED ECU and a 5 wire O2 sensor. Is this correct? TomO, please chime in if I'm missing something or if you have a write up on this.

Fed emissions ECU, 5 wire O2, and a socket for the 5 wire O2 are what you need for parts. LCA is the person to look towards for the wiring though. There is a post by him in a thread somewhere around here on the wire details though. Try searching "O2 conversion".

Thanks TomO

lca13, congrats on getting that conversion squared away! Is there any chance that you could share all that precious info that you've compiled? I'd like to convert my CA VX.

Mango, where do you live? I bought a fed vx ecu a few months back. I haven't done the conversion yet, but am planning on doing it this year. If you live in the bay area (CA), we could get together and work on the conversion. I'm in need of a connector and the o2 sensor.

I live in Oakland and would be interested in this mod (I, too, have CA VX). I'm just getting it back on the road after doing some major bodywork.

On another note...
Earlier in this thread there was some talk about front brakes being stiffer than rear brakes. I know most of you already know this but:

The shoes in your drum brakes only engage the drum surface when you depress the brake pedal. Then springs pull them back away. This is nice because there is no friction when it isn't wanted but the downside is that after a while the shoes wear down and they don't engage the drums as much. Yes, there are mechanisms in place that supposedly self-adjust but none of them really work great.

The pads on your disc brakes are always in contact with your rotor. They don't retract when you take your foot off the brake, they just stop squeezing. The calipers do not have any mechanism for retracting, that is why you have to force the piston back when you put new pads on. Disc brakes always have some amount of friction (beyond the fact that our front brakes are tied to the tranny/engine as TomO pointed out).

So what we gassavers really want are drum brakes all around. Unfortunately there isn't a reasonable swap for this. I don't know of any front wheel drive cars with drums up front, they just don't work as well. Maybe Honda or Toyota will come up with a "no braking/no friction" disc brake set up one of these days.

In recent years they have designed the caliper seals to provide some retracting force on the pads so the drag is reduced. Absolutely have the rotors turned to minimize drag. I have seen replacement rotors that were warped 20 thou. We turned them whether they were new or reused.

regards
Gary

Really? That's great. I wonder if there are any that we could retrofit to our brakes.

If you're looking for front drum brakes you can get the old Beetle. It's not FWD but it's Rear engine so you don't have the drivetrain losses like you do with RWD or AWD.

Drum brakes up front is really unsafe. Drum brakes suck, they only persist because they're cheaper to manufacture. But they can fill up with water. They easily overheat. They're overly complicated. Nobody here wants to trade safety for mileage.

Disc brake rotors supposedly "beat back" the pads. But yes it is true that they drag some especially on older calipers. Honda doesn't make the best brakes in the world, but they're also not the worst.

I'm pretty sure the OP could have saved some grief if he had found a "B18C into a VX" swap guide and worked backward. They convert the 5 wire O2 to 4 wire.

There is nothing to fear from "15 year old wiring". The wiring itself should be as good as it was when new. Sure, the tape is dry and cracked in places...

Hey, I drive a Metro! :D


Sorry I couldn't resist....

gary, that is very nice of you to ask. I would definitely like to be part of a swap so I can get more info on doing my own! Unfortunately, I live in San Diego. Thanks again and best of luck! Please post back with how it went after alls said and done.

Wow, I haven't been back in a while and there are a handful of replies. Hey guys, can you take a picture of your new O2 connectors?
Gary

I wanted to post my extrodinarily easy and positive experience converting a 1992 Civic VX California emissions to a 49 state Federal lean burn version.

As posted elsewhere, many (all?) 1992 CA Civic VX's came with the 5 wire o2 sensor installed and that included mine, so nothing to do there. The only thing I had to do was to unplug the exisiting CA ecu and replaced it with a used 49 state ecu that I purchased.

Done, perfect, immediately have a fed version lean burn mode Civic VX. This will go down as one of the easiest modifications with a big impact that I have ever done.

Just so you guys now that this swap out can be stunningly easy to accomplish given certain senarios.

Re: lca13's 93 California VX Thread
 

IM glad to be part of this forum and love my vx.... im in the bay area california and would love to do this hopefully easy swap out can anyone help me?