Ready to purchase an A/F gauge to ***ist in fine tuning but I was really hoping to find something more for use as a diagnostic tool rather than a permanent gauge inside the car. Any recommendations? I don’t object to the gauge style but I plan to remove it after the carb is perfect and plug the sensor hole in the exhaust until needed again. I did see one unit called Carb Cheater that sent information to your phone via Bluetooth which I thought was really cool. Sadly, however, that system used a baseplate under the carb that was intended to be left in place and somehow it modified the A/F ratio on a continuous basis to keep everything just right during all conditions. So not really what I was looking for. I just want information so I can tweak carb components then pop it out and use it in other cars. I imagine every carb tuner but me already has something like this in their ****nal.
I have this one mounted in my truck, https://speedhut.com/gauge-applicat...**og-out-o2-gauge-8-5-18/?dd-link=0ldtcryzj5b I watch it all the time and drive by for better fuel mileage. It's also a very quick way to see if it's not running right or the gas is bad. I can tell if the octane changes by watching the ratio's. With this gauge, you can mount the O2s on a stick and shove up the tail pipe for temporary tuning. Mine has a power, ground, and light wire. Speedhut replaced the O2s once cause it was reading strange, I call and ask about it, with no hesitation, they sent me a new one. Really good customer service. I also have an old hand held unit that goes in the tail pipe, with a couple alligator clips for power. It works decent but not as good as the head pipe mounted O2s.
I've got two from these guys. I did a lot of searching, and researching the subject. I've got a single readout and a double readout gauge. Only one car is running though. https://www.innovatemotorsports.com/shop-all/measurement/wideband-air-fuel-ratio.html Your comment - I don’t object to the gauge style but I plan to remove it after the carb is perfect and plug the sensor hole in the exhaust until needed again. You have another thing coming...if you think that the word "perfect" is in the vocabulary of this task ! Plus LEAVING it in the car, AND working may tell you things about your engine BEFORE...bad things go too badly, before it's bad enough for you to catch it without the gauge !! Mike
That just isn't effective with modern gasoline, and at idle and part throttle cruise you're still in the dark. My Autometer A/F monitor has dialed in 4 cars in little time. You'd be amazed how easy it is.
You can install/remove/install any of them, so get a decent one. I'd get one that has two readouts so you can monitor both exhausts simultaneously. Nothing says both sides are getting the same fuel/air mixture. You can move it from car to car, but you will probably like having it. Go with a digital read out. Innovate is a good one. You can get a kit with both sensors at Summit for about $300.......thats what I bought. Buy a cheap infrared gun to check exhaust temps as well....that will help diagnose if all cylinders are similar or if one is the culprit. What I mean is that if one cylinder is not performing well it will cause the overall F/A ratio to be off. So rejetting etc. won't solve the problem. If all exhaust manifold inlets are nearly the same, then altering the F/A ratio should produce the result you want.
I do that now but I’d like to go next level and get my carbs as close as possible in every driving condition. Setting idle or primary main jets is a breeze but I want to see all the transitional information in between.
Plan on a lot of test drives, it doesn't take long to see where the issues are, but getting it all inline takes some thought and parts changing. I was tuning dual W-1 Carters, so before hunting down parts, I used the spares I had and sanded them down where needed or solder them up thicker. Once I was pretty close, I went looking for Carter metering. I made a crude throttle pedal position gauge using heavy cardboard, a spring loaded pointed, and a string tied to the throttle pedal. With this I was able to see how much throttle I was using so I knew which step the metering rod was on. The W-1s have three steps, so knowing where the throttle pedal was helped. Turns out 80% of my driving uses less then a 1/4 of the throttle. ( Chevy 250 inline six. ) Mine will change 1 full point on the gauge by changing the metering rods hight by only .040". I use a dial caliper to set them, I also used a dial indicator to set both throttle openings the same. Winter to summer changes the reading, so I adjust as needed, it's just to easy not to have it right. Mine stays above 15.5:1 most all the time, it runs better on the lean side then rich.
I have an Innovate that I use to get the carb right, and then it goes back in the box. Long ago, I bought a tailpipe adapter with a long cord so I didn't have to install a bung for the O2 sensor. It's worked well for my purposes so far (although the 02 sensor did fall out of the tailpipe of my Riviera last year - no damage, but it did take a little ride on the pavement). The most important thing about the wideband is to NOT try to shoot for some arbitrary number when tuning. The car will tell you what it wants, and not all cars want to run super lean. Some will cruise at 15.5:1, but more often (in my experience), driveability will suffer. Plus, you are also tuning the idle/transition circuits, which are tougher to change but are often an issue.
Good point! I actually have the car running and driving excellent right now but I’m very curious to see if there are rich or lean spots that might benefit from finer tuning.
I definitely don't have one. I still read plugs and pay attention to exhaust smell/colour. I was chasing an issue that turned out to be fuel delivery, and don't think the fancy gadget would have helped me find it any easier even though I considered getting one before I found the issue.
I have the AEM unit like the one pictured. You find yourself staring at it more than you should be. Happy when you’re coasting along with 16/1 afr and cringing at 11/1 on an uphill grade. There a great tool for drag racing and that’s where I pay more attention to the readings.
I put an Aeromotive O2 sensor and gauge in my off topic car a couple years ago before I had even fired the new engine.After putting quite a bit of cash into a new engine i wanted to know exactly where my a/f ratio was during break in. It was extremely helpful and I’ve used it continuously since then. I’ve learned quite a bit about tuning this particular carburetor. They would seem out of place in an on topic car but I plan to install one in my 63 Grand Prix soon. I guess I don’t see it as that big of an issue, particularly since it is an informational ***istance tool and not used as for appearance. It could also save your engine if something malfunctions or breaks. Whether we like it or not, technology and time are going to march on, and availing ourselves to some of the technical benefits is a boon for us. The old tried and true tuning tools such as vacuum gauges and reading plugs, and “stick to it” tuning habits of our old hot rods are great, but it doesn’t hurt to back them up with something like an a/f gauge to make the young kids realize us old hats know a thing or two.
I bought this one about 10 yrs ago. At the time it was around $200.00 Very useful tool for dialing in carburetors, especially the part throttle ratio. Once dialed in they all get better mpg, drivability, and the closest thing to real FI, it's a amazing. https://www.summitracing.com/parts/...GbJcSZun9W8PKNgXUpW4_orzPINoEE8oaAuF0EALw_wcB
I have FAST . Uses two wide band o2 sensors or can use just 1. Has a record and playback feature I like.
FYI. The most important thing with any A/F meter, is make sure you have absolutely no exhaust leaks. Any leak will fool the sensor into showing the mixture as lean. Best to have the sensor as close to the engine as possible while reading all cylinders on the bank. Those tail pipe mounted sensors could be a problem, due to most mufflers have drain holes. Plus air can back feed into the pipe at low engine speeds.
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