Testimonials from 427 Convertible owners:

Robert G – 427 Convertible

Unlike many of the other reviewers, I did not mind the firm ride of my MRC since my daily driver is a 2013 Z06 with non-MRC suspension. My MRC seemed compliant by comparison. My hope was that the New Super Sport upgrade would not soften the ride too much, and would improve cornering speeds, handling in bumpy corners and on washboard roads, and reduce tramlining. I am happy to say that the upgrade has exceeded my expectations.

 The most noticeable improvement is the enhanced traction in bumpy corners, especially those which make both your heart and the car jump a few inches to the outside at high speed. With this improved grip, you can keep the power applied with confidence and attack the corners with greater speed. While tramlining is not gone, it is greatly improved, and the steering feel is lighter. Add on top of all this; an overall improvement of tire grip/handling on washboard roads, no noticeable increase in body roll, and a reduction in ride harshness (less jarring & quieter), this was a win-win upgrade. I am extremely pleased and highly recommend it to anyone with an MRC suspension. Many thanks to you for your continued work and support of the C6.

Bob J – 427 Convertible

I left Jim and went on a 120-mile ride into the Laurel Highlands with our Corvette group. It was a good test since we hit highway and secondary, and maybe third-rate roads. I felt the car in tour mode was much more refined in how it handled expansion joints and other road imperfections I encountered. Once we hit some secondary roads the Sport mode really felt great. Especially in the twisties where I felt the car was under more control.

No doubt, with Jim’s guarantee, I suggest you give this upgrade a workout. No second guessing my purchase. Thanks Jim!

Jim D – 427 Convertible

I have to give a huge thumbs up to Jim’s upgrade. I drove 148 miles this morning. What a difference, I am extremely pleased with the upgrade. It’s like I drove up an old car and traded for a new one. Day and night difference. If you’re on the fence about getting it done…..just do it! Money very well spent.

thanks again Jim and very nice meeting your wife as well. You’re both fabulous!

Eric R – Auburn, WA – 2013 427 Convertible

Hi Jim

I wanted to take a moment to let you know that the module you returned to me is installed and works great! The ride is much more compliant on city driving, while freeway speeds also show marked improvement. I would highly recommend this suspension upgrade to everyone that has MRC on their C6. Again, great job, thanks Jim. ER


Eric R – Auburn, WA – 2013 427 Convertible

Hi Jim

I wanted to take a moment to let you know that the module you returned to me is installed and works great! The ride is much more compliant on city driving, while freeway speeds also show marked improvement. I would highly recommend this suspension upgrade to everyone that has MRC on their C6. Again, great job, thanks Jim. ER

Fred Rice – Klassic Rides LLC – 2013 427 Convertible

I’ve made a point of driving my Corvette almost daily since you installed the MRC upgrade, and it truly is a very different and much improved car vs the stock programming & ride.  I’ve spent time driving the car on city streets, neighborhood streets, and interstate highways & I’ve used both “Touring” & “Sport” settings in all environments.


You were right:  I now leave the MRC set on “Sport” virtually as a default setting, vs using the “Touring” setting as the default setting and the “Sport” setting as optional.  While both modes are much improved, the improvement in the “Sport” setting is most dramatic.


The car now handles much better. 


  1. No “darting” on highways.  As you probably know, with the wide tires on this car, “darting” was a problem.
  2. No “dancing” sideways over small depressions.  This was a problem with depressed manhole covers, resulting in the car “dancing” to one side in curves.
  3. Bumps in the road are now absorbed much, much better.  Ride and handling is so much better.
  4. Road noise is much reduced. 


I’ve also noticed that the clutch engages much smoother than before, and putting the car in motion is so much easier than before. 


Overall, the car feels tighter, more solid, and more under control.  If I didn’t know that you had upgraded the MRC programming, I would have thought that someone had installed a major suspension modification.  It truly does drive like a new car!


Thank you for making this great upgrade available.  It really is a modification that all C6 drivers should install in their cars!


On a related note, we here at Klassic Rides would very much like to be able to provide installation of your MRC upgrade to Corvette drivers in and around the Charlotte area.  We’ve been in business for over 15 years, and our customer base extends from Virginia to Florida along the Atlantic Coast, and west into Kentucky and Tennessee.  I would very much like to discuss how this could be a benefit to both you and us. 


Dan L – 2013 427 Convertible

Jim, thanks for meeting me last Tuesday morning. The upgrade made a big difference in my 427. I took a favorite back road on my way home from Richmond, most of it in Sport mode, and the difference is fantastic. The old sport mode was too harsh for normal roads, but now it rides great and I feel more control. Steering feel is great. The best upgrade I have done to this car. Thanks again.

Ken W – 427 conv. Programmed at the NCM Caravan

One of the happiest and coolest places on Earth! National Corvette Museum 25th Anniversary! Had a great time talking with Jim and Terri Mero after Jim did his magic reflash of our much loved 427’s magnetic ride suspension. Already we sense a wonderful difference! The Vette drives better than ever! Tomorrow on track we will learn more! THANKS Jim & Terri!

How cool to have THE GM Driving Engineer who has set so many lap records and been the man behind so many Corvette suspension tuning technical successes to get personally involved with OUR Corvette!

Etienne K – 427 Conv. Flashed at Carlisle

After strolling the grounds at Carlisle, I came across Jim’s booth. I was very interested. The settings on my 427 convertible could have used some tuning. I have felt that the Tour mode was too harsh for street and highway driving. The joints and bumps were getting harsh in the seat. Jim and his wife were very helpful in explaining the upgrade and the warranty. We decided to move forward with the tune. On the way home from Carlisle, we were pleased with the ride. Much smoother. I haven’t tried the Sport mode yet, but it is like the Tour mode, the settings should be great for the limited track time that I do. Good investment in a car that I hope to drive for many more years.

Michael M – 427 Conv – Flashed at the NCM Caravan

The trip home was great, overall ride was greatly improved. Car felt more stable, handling and ride was more responsive, but the best thing was what we did Saturday before we left. We put it back on the track and man did it allow me to show out for everyone!!!  It handled way better with on the track that it did the two days before.  Thank you, Michael and Sherri–

Keith – 427 Conv. Upgraded at Carlisle

Jim did his upgrade on my 427 convertible at Carlisle. Quite the improvement. The ride home was considerably smoother than the ride there, both done in Tour mode. I haven’t tried Sport mode yet because despite some incidents of aggressive cornering in an effort to uncover hiccups, the car remained flat and balanced while still delivering a smoother ride. It also maintained better road contact when going over bumps at speed. Very happy with the results. Now when Jim and Terry find their way to Vero Beach I can get my ZR1 tweaked as well. Thanks Jim and Terry, Keith