Innovate MTX-L Wideband Oxygen Sensor Kit, 3844 is a "Permanently Mounted" Wideband gauge that fits 2 1/16" Gauge holes (Standard VDO!) Whether you are desiring maximum HP, or MPG, you need to know your fuel mixture EXACTLY to achieve your goal. This device lets you take the guesswork out!
Complete All-In-One Air/Fuel Ratio Gauge Kit. Includes: Gauge, Silver Bezel, Black Bezel, White Faceplate, Black Faceplate, Bosch Wideband O2 Sensor (LSU4.9), 8 Ft. Sensor Cable (Overall length 10 ft.), Exhaust Bung, Program Cable (Only needed for Datalogging and to change the Fuel Type Setting), Software CD, and Quick Start Guide.
WOW! Jetting and tuning your carbs or FI was never so easy! We have upgraded our A/F gauge kit to the Innovate Wideband unit, because the price of a wideband gauge has dropped so much.
http://www.thesamba.com/vw/forum/viewtopic.php?t=293837 is a great tuning thread
Next, simply weld the supplied bung into your exhaust system (or use our flange adapter), after the collector and before the muffler. Screw in the sensor, run your wires to the dash, and plug them in to your fusebox (you need power and ground). Next, DRIVE IT. By noting your engine RPMs and what the Unit is reading, you know whether you are too lean, too rich, or just right. Our tuning instructions tell you which jet to change to bring you where you need to be for PERFECT running; this means clean plugs, top mileage, no overheating, and long engine life.
Wideband technology has progressed to the point where they are affordable (they used to be >$3k!). Use this gauge once, and you won't understand why you didn't put the $ down earlier!
Even if you have never done this before you can properly jet your dual carbs relatively quickly with the aid of this kit! It sure beats Seat Of The Pants tuning!
The ratio of air/fuel for stoic is 14.7:1. While this is chemically correct, it is NOT CORRECT for the Otto engine. Gasoline is a MIXTURE of many components, of which have DIFFERENT octanes and chemical properties. The "octane rating" is the average of these components.
We recommend tuning in the range of 16:1 for light throttle (progression circuit), and 12.75-13:1 from 1/2-Full Throttle.
When using this gauge, you should notice a momentary "lean condition" during and just after a gear change. IF the gauge is responding this way, it's working properly. The fact is, almost everyone that gets this kit and installs it on their engine finds they are richer than where they thought they would be ("I thought I was perfect, I had no idea I was that rich" is a common statement).
Leaning it out a little bit crisps up the engine, freeing up more power.
The gauge is NOT something that will solve all tuning problems! It should be used as one more tool in your bag of tricks, and lets you SEE where you are regarding A/F ratios. Simply see where you are on the gauge and note the RPMs you are at, and you have a darn good idea of which jet to change to bring your engine WHERE YOU WANT IT TO BE. Obviously, race engines run richer than street engines, so "generic" instructions don't work.
The best thing to do is use the kit, and LEARN FROM IT. Find out how the engine reacts to changes, and you can SEE the results on the gauge. When you see the A/F responding to your driving and jet changes, the jetting procedure (and the effect of the different jets and carb circuits) will make so much more sense. Once you understand this, you will be a better tuner even without the gauge!
Most guys find it pegged full rich, and think the damn thing is broken (it's not). it just shows you that your jetting is off of ideal.
Our recommended procedure is to start lean and richen it up until you are where you want to be. Start lean, and slowly richen it up. The A/F gauge will NOT help a lot on setting up your accelerator pump squirt, you can do that by adding fuel squirt until the hesitation is gone.
If you read the "manual" and jet the thing for stoic, the engine will backfire and overheat bigtime. The combustion chamber of an Otto engine is a MIXTURE of rich and lean spots, hot and cool spots, etc. It is NOT a mixture of perfectly mixed air and fuel. THIS is why you need to run richer than "stoic" (chemically correct ratio), since your "worst case" A/F mix must be richer than 14.7:1, and to accomplish this, you must be richer than that, since there are LEAN SPOTS in your combustion chamber on every cycle of the engine. This may require 13.5:1, or 13:1. We have found that this range is where you have the best mix of performance, cooling, and engine life for the VW aircooled engine. Most guys don't even realize the stock VW had A/F of around 11.5-12:1!
When I see guys with IDAs and getting 12mpg, THEY ARE TOO RICH. One guy with this kit on his 2110 street engine gets 30mpg with IDAs and 37 vents, and runs cool and hauls @$$. I guarantee you his jetting is darn near perfect. You aren't going to accomplish this combination of performance in a weekend! He is STILL fiddling with getting it PERFECTLY dialed in, even after months of tweaking and tuning.
Make your changes until you get your desired reading and drive it. Make ONE change at a time, and drive it a few hours (not blocks) and see how it responds. An awful lot of the gauge's operation can't be described, but you DO learn what the engine wants and needs after you have used it, and it's an invaluable tuning aid.
RETURN POLICY: ACN's policy on this item is that if you have a problem with the unit, you deal with Innovate directly. Our involvement is to verify that you purchased the unit from an approved dealer, and we will help you properly tune your car (if you need guidance). The reason for this policy is that Innovate won't be able to be of any VW Specific help in tuning, and Innovate is more technically savvy on the particulars of the unit to make sure you are connecting everything properly.