Gents, whats the best AFR gauge for our application? All feedback welcome.

I'm planning to get a tune down the road some. Maybe after headers and exhaust.

*gauge, not guage

 

I've had this for a while. I just need to get around to installing it.


I know a lot of people like AEM gauges as well, but this series of Autometer gauges matches the factory gauges pretty well.

 

:
another guy here who has on hand but yet to install

thought it would be a good idea to monitor real time and my Scorpion headers have the bung already

my research & preferences led me to an NTK unit . . .


. . .which would sit on my Euro parcel shelf -

- but also had a Speedhut fabbed up because i love analog instrumentation
& the NTK unit has a port to plug in to drive the gauge, so the plan was to mount the analog gauge as primary reference point while the NTK box was kept more tucked away on the shelf

 

I have an AEM AFR gauge in my car with a wideband.

 

Oldboy didn’t explicitly say, but for accurate afr and tuning usually a wide band o2 sensor is used like in his kit. Although it’s usually not necessary with basic mods so depends on your needs. Sensor can always be added later, unrelated to your gauge.

 

I've had a few recommend Autometer and AEM gauges. the "Innovate" brand also seems popular

https://www.innovatemotorsports.com/

that Autometer does match the look pretty close (judging from the pics)

 

the analog is my taste also. really like the look of this one but wish it had matching colors for the mini

https://www.innovatemotorsports.com/...tio-gauge.html

I should add, i can see how some would prefer a digial display, for preciseness

 

Feel like i should have asked this initially. How important is the AFR gauge for tuning the r50 / r53 engines? Some have told me that its more for engines w/ turbo chargers

I plan to do intake, hearder and exhaust only.

 

Since I am a complete idiot when it comes to AFR (amongst other things),; Perhaps better left for a different discussion - So upon installing and monitoring an AFR GUAGE - if the values/mixture is off ; How does one make an adjustment? Tuning?
I mean, I get carburetors (and injectors) but ECU's are above my head.

 

I worked close to a dyno tuner a few years ago and picked up a little information over the 18 months or so that I was there.

When dyno tuning, generally, the tuner will put their own wideband O2 sensor in place of the stock, front O2 sensor unless the car has a test bung on their header to put their sensor for tuning. During a pull, it is critical to not run lean at WOT, so having a reliable AFR is very important. I have been told that cars that come in for dyno tuning, some turners will use the aftermarket gauge in the car, others prefer to instead plug in their own AFR for tuning. This particular tuner's AFR looked like the NTK unit that @Oldboy Speedwell posted. All cars, whether N/A, turbocharged or supercharged had the AFR sensor hooked up during tuning.

Assuming there are no issues with the engine (fuel delivery, air leaks, misfires, etc...), tuning is how adjustments are made. A tuner will be able to adjust various parameters to get the AFR where they want it. Sometimes, they will find problems with the car (weak fuel pump, injector sizing too small, MAF/MAP issues, etc...) if, for example, they max out the fuel injectors and still cannot get enough fuel into the engine, or in a case I saw, the meth injector nozzle was too close to the MAF and fouled it when spraying.

Again, I am not a tuner, I just picked up little bits of tuning info working a few doors down from a tuning shop.

 

If I was only doing an intake, exhaust, and header, I wouldn't bother with it.

I run one since I have bigger injectors and a tune and want to dial it in for track use.

 

there is a fuel table, y is rpms, x is load. like this pic below. ecu reads the table for fuel delivery. Ok i've literaly told you all i know about tuning now

Tuner would tweek the values in the table

 

I thought so. "All cars, whether N/A, turbocharged or supercharged had the AFR sensor hooked up during tuning". thank you for this feedback, ghostwrench

 

so if plan to get a tune then afr is needed. I think that is what you are saying. Correct, GLTHR53?

 

AFR is accessible when tuning but not easy adjustable because you need laptop/software to make changes. You want to run as lean as possible because that's where the most HP is found but you also run the chance of burning a piston if running too lean. I prefer a richer mixture just to guard against destroying a piston (I don't track) plus the richer mixture gives you a nice exhaust burble even with a one-ball exhaust like mine.

 

Not necessarily. Some remote tuners want you to have one so they can verify the AFR is good through the rev range since they aren't tuning the car in person. If you get it tuned in person, it'll be a better tune but also they'll usually put a wideband on the exhaust to monitor AFRs so you won't need one in the car.

I like having AFR on track so I can see if there's an issue with the car and it's running lean since I'm running up in the higher revs all day long.

 

A belated Thank you to you guys for clarification and explanation!

 

granted, on the track its clear that it would be a good thing.

for tuning, if you take the afr reading at the exhaust tips would it be as good of a reading as taking it from the header? is there an optimal position to take a reading?

 

Instructions for installing the wideband sensor for my gauge are to put it as close to the collector as possible. Upstream of the catalytic converter.

I had a bung welded in for my wideband O2 prior to installing my Milltek header. I have it marked in the picture.


I had temporarily installed the header to choose this location. By my testing, the sensor should fit. It may be close to the bulkhead though.

 

For an in car gauge, most recommend putting it at the collector (that's where mine is). There are pluses and minuses for both location from a tuning perspective but I'm not an expert who can talk on this topic much. The tip placement sensors are only for dyno tuning and good tuners can get the info they need from it.

 

thank you, both. that location makes sense 🙏