Ford Muscle’s 2020 Shelby GT500 Gets Suspension and Wheels
“Round two. Fight!” rang in our minds as we moved on to the second round of testing our 2020 Ford Mustang GT500. Unlike the Street Fighter video game where pressing buttons to release random kicks and punches works , we decided to take a formulated approach to deliver results. In this round we are focusing on our suspension and tire package to hopefully improve on our last outing.
In our last round of testing we used stock tires at stock power levels. Unfortunately, the power of the supercharged 5.2L Predator engine was more than the track conditions could handle. A festival of pedals emerged on our first pass and a spooky wheel jump the next. This caused us to throw in the towel for the night. Even outside of these difficult circumstances, James Lawrence managed to land a 7.68 to 98.94. Decent weather considering the track surface was not much better than a lightly prepared street.
We had planned to add power enhancement products immediately after our base races, but then found that the chassis needed more of our attention. We knew that adding more horsepower would only magnify the problem. It wasn’t a lack of power, but a lack of the proper chassis setup that was holding us back. We decided to focus on tuning the chassis rather than the engine. On the program, a BMR suspension and a set of Forgeline wheels wrapped by Mickey Thompson AND Street R Drag Radials.
Our Shelby GT500 objectives
At this point, I’ll remind everyone of our goals for our 2020 Mustang GT500. Although Lawrence has raced and won the NMCA series, this car won’t be a test bed to build the fastest GT500 on the planet. We plan to keep this construction a simple bolt on the case. These products will show which modifications help and to what extent. These products are intended for GT500 owners who appreciate the performance of the car, but also the comfort that Ford has provided. We also want these aftermarket products to fit 100% with no permanent changes. This allows owners to return to stock without a problem. With that in mind, we continue to improve the chassis, but also take noise, vibration and harshness (NVH) into consideration with every movement.
Our first step in preparing this production beast track was to adjust the suspension. The 760 horsepower powerhouse combined with a poor track surface required a call to the right people to BMR suspension. We discussed the issues we were having and their team suggested specific parts to rectify them. Within days, the solution arrived in the form of red powder coated tubular pieces. Our mission for this round is to reduce the jumping and wheel slip encountered during our basic tests.
We knew we had to tackle the jump wheel first. On our last run, the wheel jump triggered torque management and killed any chance of a good ET. While electronics saved our parts this time around, skipping the wheel has the potential to cause significant transmission damage. Damaged parts are never fun, so we decided to cut them down as best we could. To understand what parts we need, we must first diagnose the cause of the wheel skipping. In the case of the S550, the major problem is the movement of the cradle.
Cradle socket locking kit
]The cradle under load can move in several directions. The original cradle bushings were built with NVH in mind, not performance. Unfortunately, that means he doesn’t appreciate the amount of power thrown at him during a dig. Fortunately, BMR has a solution with its IRS Cradle Ring Lock Kit. The kit uses a set of locking rings and a locating washer to secure the cradle. It is also 100% bolted with no modifications needed.
The way the locking kit works is that the billet aluminum top ring locking rings capture the inner ring sleeve and the outer ring lip. The lower ring locator washers capture the lower portion of the inner ring sleeve. This captures both parts of the inner bush sleeves and almost eliminates movement.
What’s great about the lockout kit is its ability to be installed with simple hand tools as no modification is required. This is a 100% bolted case using existing bolt holes and hardware. Locking down keeps creatures comfortable as little to no increase in NVH was observed. Locking removes 80-90% of cradle movement!
BMR Differential Bushing Inserts
As we were already this far into the chassis, we decided to install BMR differential bushing inserts. Even though our Mustang’s rubber is new, it is still subject to exposure, road salts and other harsh environments. Simply put, the original rubber cannot compete with the polyurethane inserts. The new bushings double as an increase in stability and preventative maintenance.
BMR IRS Support Brace
To complete our suspension review, we added BMR IRS support brace. The BMR reinforcement has more connection points limiting the movement of the subframe. This will help prevent wheel spinning and therefore wheel skipping. Besides having practical use, it also offers impressive underbody color and look. This product is not permanent and does not add any NVH, so reverting to collector status is a few bolts away.
No action without traction
Next on our list was to tackle the loss of traction. While throwing stickers on the stock wheels might have worked, the sad truth is that the stock 20-inch wheels are too big to provide good sidewall as well. Lower profile tires will result in less bite and more spin. We decided to go with a set of Forgeline wheels. Forgeline has been at the forefront of road racing and drag racing for years now. They produce extremely strong wheels that are also lightweight and allow for great braking configurations like those found on our GT500.
For this GT500 we decided to use a set of Forgeline GS1R wheels wrapped in Mickey thompson ET Street R. GS1R wheels are made from a simple forging of 6061-T6 aluminum. We wanted to maintain the right attitude up front and stayed with a 20 inch, 8.5 inch wide wheel. At the back we lost 2 inches in diameter while still remaining 11 inches wide. We decided to take it a step further and run a heel lock setup. This will allow us to prevent the tire from slipping on the wheel while keeping the bead in place at high speed. Exaggeration? Maybe, but the wheels are crucial in building a successful vehicle.
So after making all of these changes, it was time to see where we were. The slip bands offer little to no consistency, but for our testing purposes, we came back to the same trail. Like last time, our first run was the fastest and the fastest. Instead of relying on the build, we slowed down and the GT500 blew up eighth to 7.2-102 MPH. It’s almost a half a second faster and picked up over 3 mph on the top end. These are huge payouts for any drag racer. On a properly prepared surface, these gains would be exponentially better.
Now that the frustrating experience of jumping or spinning the chassis wheels has been reduced, we can begin our transition to producing more power! The fight will no longer be linked to the chassis, but to a detention against our store in love with power. I know I will be constantly checking the drawing board in hopes that “bolts and e85” have been replaced with “bigger fan and nitrous”. Unfortunately, that is not our goal with this release. So get ready for next week as we swap out pulleys, add a few bolts, and bring the corn juice to this amazing GT500.