If we want to leave this hobby of vehicle performance and personalization for the next generation, we’re going to need to do it responsibly. “Emissions” is a dirty word for many performance enthusiasts, the elephant in the room. We can all see what has happened in our industry over the years. Manufacturers, distributors, and shops have been fined for violating the Clean Air Act. The laws have been on the books for decades. The way they are written often reads as a guilty until proven innocent situation too with how they treat “tampering.”

But there’s still good news here. We live in the Golden Era of performance. Never before have so many incredibly powerful vehicles been available on the showroom floor, yet they all pass some of the most stringent emissions standards ever seen. The number of new 500+hp vehicles available today is impressive. At the original writing of the article, GM had not yet released the official numbers on the LT7 in ZR1. Spoiler alert: 1068hp and Bin125 emissions compliance. More good news, our testing has proven that we can make great power with catalytic convertors intact in the aftermarket.

In the article, I also discuss some of the common issues that may lead to poor emissions. Vehicle maintenance is a key factor here. Luckily, as we pointed out in the recent project with Summit Racing Equipment, performance enthusiasts are pretty good about normal maintenance.

Check out the Summer 2026 issue of Hot Rod Magazine for the whole article. We’ll have more great stuff like this coming in the future too. Thanks again to their editor, John McGann for helping get this message out there as we protect the bright future of Hot Rodding.

Some of you may have heard that we were testing a bunch of widebands to see how they compared. We opened up the testing and a few companies and good friends sent us additional units to test too. The testing results are finally in after a long time prepping and coordinating.

It’s no secret that we love our laboratory grade widebands here at Calibrated Success. Specifically, I’ve been using ECM hardware since 1999 when I got my original LambdaPRO and never looked back. Being able to have a reliable 0-5v analog wideband signal that could be integrated with SCT, HPTuners or almost any other aftermarket tool was priceless when tuning.

It served me well, and I eventually added others like the AFM1500 (with Serial communication that could integrate with EFI Live), Ballenger AFR500 (also made by ECM), and eventually my latest pressure compensated LambdaCANp. These devices remain my gold standard by which air-fuel ratio is measured in most cases. Although I have also used many of the other units out there too, with mixed results. So we decided to gather as many as we could and test them simultaneously in a controlled environment to see just how wide the spread was across all these different widebands.

Dr. Davis is one of the few remaining professors still working at Kettering University that I had the pleasure of studying under when I was there long ago. He was nice enough to let us come use his lab and engine to perform the testing that would feed our obsession with lambda data. Their 2.0L turbocharged GM LTG engine was a great candidate because it’s fairly tolerant of running at a wide range of lambdas at various loads and the turbo itself does a great job of helping to mix the exhaust so that all our sensors could get an equal look at what was pumping past them. We made some other changes to the exhaust to further improve mixing and started taking data.

What we found was there most aftermarket widebands are actually pretty decent for general tuning work as long as we recognize the noise factors present in this kind of testing. In this limited comparison, it’s tough to declare a clear winner other than our rock solid laboratory grade units. This steady state testing is really just step one when making comparisons. Ideally, we’d test aged units also to see how they stand up over time since everyone had the benefit of a fresh sensor in this test. That contributed to an overall good showing for almost every unit tested. For professional work, we’ll stick with our professional gear. But for the casual DIY tuner, it’s good to see that some of the more affordable options can work well enough in many cases.

Check out the full article over at HOT ROD Magazine.

In a recent article written for Hot Rod Magazine, I dove into the finer points of how modern 6/8/10 speed automatic transmissions work so well to keep the engine right in the sweet spot for acceleration. They often do this with the torque convertor locked most of the time. This means we only care about the slip RPM (K-Factor) right off the line, where traction is often a challenge anyway. The same actually holds true for when we’re looking for peak fuel economy, but who can think of that when we have drag races to win? With more ratios to choose from, the game has changed.

Nailing the example, I used some datalogs from a friend’s 9-second street car to show just how well a modern 8-speed automatic runs.

As long as we’ve done our job mapping the engine correctly, these modern transmissions do a great job of executing quick shifts that put the engine right where we want it almost all the time. Better yet, they do this without needing a change to the torque convertor to something that trades more power for slip.

Read the whole article HERE.

What do we do when these are too small for the application?

Greg Banish discusses the challenges of diagnosing and dealing with a turbo sizing mismatch in the latest article for Hot Rod Magazine. In this case, what started out as a properly sized turbo quickly became a problem when other upgrades were made to the engine. Adding more airflow is usually a good thing, but this time it has us struggling to deal with that increased flow in a limited exhaust housing size. We took some measurements to accurately assess the problem. Then we took some more measurements and formed a theory on the bench in the tech center. Finally, we brought all of that to the chassis dyno to see how it really worked. The results were eye opening to say the least.

Using a backpressure measurement during testing really helped us see how much stress the smaller turbines were putting on the whole system. It also explained why we were having trouble getting the desired boost levels even though the compressors should have been big enough for the engine. Putting all of this together follows some of the work we routinely do for some of our consulting clients. These lessons can often be translated to other programs, whether the engine is bigger or smaller than the one tested here.

Spoiler alert: we didn’t completely solve our problem in part 1. We did learn some important lessons that we’d like to share about diagnosing the mismatched turbos and how we can deal with them. We also set ourselves up for a strong comeback in part 2 coming soon.

It’s no secret that one of my other hobbies is audio. Car audio, home theater, reference stereo, live music, it all ties in. I was actually more interested in car audio than engines when I first got to engineering school. My Big Brother in my fraternity was an electrical engineer who had been playing with crossovers and speaker enclosure design for years when I met him. He taught me a lot about how the physics tied in to what we hear (and feel), along with how best to start making adjustments to correct what we hear. Fast forward a few more decades and I still play with sound. Sometimes I’m making it (playing music or movies) and sometimes I’m helping mitigate it (dyno cells, listening rooms). The science behind it is the same either way.

We’ll start with my recent project: a reference quality 2-channel audio setup in my listening room at home. While the Digital Signal Processor allows us to flatten the frequency response and align the flight time of music from each driver to the listener’s head at the optimum seating position, there are some things it cannot do. The DSP can’t fix diffraction caused by early reflections from the speaker baffle. These speakers were designed with minimum surrounding area to create that unwanted interference similar to the Bowers and Wilkins 801, which were my inspiration ever since I heard a pair back in the 90’s.

But great drivers will only get you so far. The room itself can color the sound with reflections and standing waves. What you can’t see in the photo above is the foam panels on the walls directly opposite the speakers. These help tame the primary reflection off the back wall, but looking deeper at the measurements, we’ll see that something is missing. Even with careful measurements and recalibration of the DSP, the room still sounds very “lively” compared to what I know is recorded in some tracks. Time to go back and look at the measurements taken with our calibrated microphone using the Room EQ Wizard (REW) software. This is starting to feel a lot like comparing ECU datalogs and calibration files now.

Yes, that looks like a lot of noise. The truth is that moving the mic (or your head) just an inch or two can significantly change the frequency response at the new position as some reflections become either constructive or interfering. That’s why we take multiple recordings from multiple positions and average them before making decisions. With an 18′ sub and over 1kW of power, I can make all the low end bass I want, but the room seems to over-deliver around 50Hz no matter what I do. Looking at the RT60 plot shows how various frequencies decay in the room. The low end clearly likes to hang around for longer than the speakers dictate.

Digging deeper, we look at the Waterfall plot and find something interesting. I saw peaks around 50, 100, 150, 200, 300Hz. This can’t be a coincidence. These are all multiples of the same fundamental frequency (~50Hz) with diminishing intensity as the order is increased.

THIS is something our brain will recognize, and should be addressed. But why is it there? Knowing that sound waves have a predictable length based on their frequency, it was time to break out the tape measure and look at the listening room again. This room is a bit irregular, so I took a bunch of measurements and looked up what frequency each measurement would correlate to for wavelength. The results jumped right out at me:

Seeing peaks at multiples of 46-50Hz is NOT a surprise in this room. Now we’re getting somewhere. We have definitive proof that our room contributes to 50Hz (and multiples thereof) noise. We just need to treat it. Treating low frequencies largely depends upon absorbing energy as the waves approach the walls. Bass Traps can be used to great effect here. After doing lots of reading, the biggest lesson I can transfer to you about bass trap effectiveness is the equivalent of “no replacement for displacement”. Studies have been done on various designs, shapes, densities, and placements. The biggest influence on low frequency attenuation is the thickness of the element. 2″ panels do just about nothing this low, 4″ panels are marginal, and 6″ really starts to work well. This means that either a substantially thick panel on one of the walls, or a bunch of corner elements could be used to have an impact upon the waves in question here.

The easiest is to add are corner traps. We can always stack additional panels in front of these or along the walls later, too. We’ll start with these corner traps that are up to 7″ deep and put them on some of the surfaces touching our 50Hz waves. Do we expect this to cure the problem? Probably not completely, but it should make a dent. We’ll take some more measurements after they’re in and see how we did. Since this is a reference listening room, I’m fully expecting to get or make some larger 4-6″ panels for some of the offending walls too.

So how does this relate to your dyno cell?

I’ve helped many shops reduce unwanted noise in their dyno rooms. Ideally, I can get involved before the room is made to help create a room with favorable geometry. This can avoid standing waves in the first place, and has the biggest impact. After that, we look at where we can either absorb reflected sounds, or break them up to reduce their intensity. Properly done, we can have a significant impact on noise emitted from the dyno room, even if the car is incredibly loud. Reducing the impact on your hearing, or neighbor complaints is a nice benefit too.

Is it better to replace the carburetor with fuel injection only or replace a traditional distributor with a computerized controller only?

That was the question at hand during one of our late night shop sessions. Check out the answers in an article I recently wrote for DIYautotune.com.