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JMS 2000 Ford Mustang GT Kenny Brown Suspension System Install - The Evolution Of Intelligent Design - Tech
We Install And Test A Complete Kenny Brown Suspension System On JMS Chip's '00 Mustang GT.
After taking some time off, Kenny Brown is back in the game. We installed the latest subframe connectors from Kenny Brown Performance in Project Shake 'N' Bake (Nov. '09), but wanted to get our hands on an entire kit to test. So we called Kenny Brown himself to inquire about his product line.
"We started by bringing back our most popular parts," Brown told us. "We were getting a lot of requests for the K-member." Though some weight-reducing changes have been made to the components, Brown tells us that "all the geometry is exactly the same" as his previous products.
The kit is the latest in a line of Kenny Brown suspension components for Mustangs that started over 20 years ago. "Our products are specifically designed for performance/street and track use," Brown says of his products. "They are robust and go through FEA testing before production." Also used by NASA, FEA stands for Finite Element Analysis, which uses computers to maximize strength and rigidity while minimizing costs and weight-ideal for chassis components.
Brown began creating his Advanced Geometry Suspension (AGS) systems in 1987 while working on the championship winning Saleen racing Mustangs. Those early renditions are what he refers to his Gen-I systems for the Fox platform, which featured a revised K-member geometry. By 1993, Brown had launched the Gen-II AGS. These components worked with Fox Mustangs, as well as the new SN-95 platform, and featured a tweaked version of the Gen-I K-member, a new fixed-strut front geometry, and a revised rear geometry dubbed "TracKit."
Today, the Gen-III AGS shares the same basic design of the Gen-I and Gen-II systems, but offers CAD-improved design and weight reduction through FEA. "All my stuff is an evolution," Brown tells us. The system we received is an AGS 3.5 design, a recent updated iteration of the Gen-III system that features low-friction bushings and ball joints in the control arms.
So when we found a car to use for the install, KB shipped us an entire kit. Our vehicle of choice, a '00 GT, was basically stock with a Vortech centrifugal supercharger. The car is a shop project vehicle for JMS Chip and Performance in Lucedale, Mississippi. So we headed to JMS, a 13-year-old parts distributor and full-service performance shop nestled between New Orleans and Mobile. It houses a parts showroom, auto and motorcycle chassis dynos and tuning, full-time installation technicians, and a full-service chassis fabrication shop.
Led by Monty Johnson, technicians Roy Snelgrove and Chris Hood teamed up to install the KB system on the JMS Chip and Performance open-track hopeful. Snelgrove began by welding the KB Extreme Matrix Kit (PN KB-29550) in place. It consists of subframe connectors, Extreme Matrix Brace, and jacking rails, and sells for $349.99. The team then moved to the front to install the K-member.
After supporting the engine with a brace from the top, Snelgrove and Hood disassembled the brakes, disconnected the tie-rod ends, and unbolted the steering rack; then they unbolted the struts from the spindles, and unbolted and lowered the stock K-member and A-arms. The new tubular K-member (PN KB-49610) and control arms (PN KB-49621) weigh over 30 pounds lighter than the stock pieces, and retail for $769 and $529 respectively.
After installing the K-member and control arms, Snelgrove and Hood installed the front coilovers. Made by Koni, the kit (PN KONI-CO) consists of Koni Sport single adjustable coilover struts, 550-pound Hyperco springs, spring tenders, isolators, and a coilover conversion kit. It's available through KB for $1,549. The team buttoned up the rest of the front components and lowered the car.
Under the hood, Snelgrove installed the KB strut tower brace (PN KB-29501) and the KB Caster Plus kit (PN KB-49041). The brace costs $199 and the caster/camber kit is $149. With the front complete, Snelgrove and Hood moved to the rear.
Out back, Snelgrove supported the rearend, removed the stock uppers, and installed the KB adjustable upper control arms (PN KB-28050). The KB pieces feature the same FEA-aided design as the K-member and A-arms, and are coated with the same corrosion-resistant powdercoat; the retail price is $249. Snelgrove and Hood then unbolted the stock lowers and installed the KB anti-squat traction brackets (PN KB-49001), which offer both stock and 7/8-inch lower mounting locations. They require drilling of the stock mount and retail for $99. Snelgrove then bolted the KB adjustable lowers (PN KB-28061CO; $349) in place and moved on to the rear coilovers.
The Kenny Brown/AFCO rear coilover kit (PN AFCO-CO; $799) comes with single-adjustable AFCO coilover rear shocks, springs, and mounting brackets. The shocks mount to the stock upper mounting point up top and to the anti-squat brackets down low. Hood then installed the rear shock tower brace (PN KB-29901; $149) by scraping the seam sealer away and bolting it to the shock towers. To finish off an already-stellar system, JMS fabricator Kenny Gunn added a custom-built panhard bar for added rigidity.
Later, JMS added a Baer brake kit and Pirelli P-Zero Rosso street tires on 18-inch wheels, and headed to Gainesville Raceway to meet us for some testing. JMS brought along experienced driver and racer Brad Grissom. Having never driven Gainesville, Grissom hit the 1.1-mile road course and pulled off a 1:13.28 lap right out of the gate, followed by a 1:12.04 and two laps in the 1:11s. "The suspension was so tight that we actually had to remove the rear sway bar to prevent the right rear tire from lifting in right turns," Grissom said. "The turn-in is so good, you feel like you're driving a Z06 or a Porsche."
After removing the rear sway bar, Grissom ran a couple of 1:10 lap times, followed by a few 1:09s-on touring street tires. After swapping to a Pirelli full-slick race tire, Grissom knocked off a 1:08, then a 1:07, then a 1:06, and finally a 1:05.30. "The car is not pushy at all," Grissom commented. "It just stuck."
After accomplishing some of the quickest lap times we've seen at Gainesville, an impressed Grissom summed it up simply. "The only car it can compare to is a BMW M3 race car." When asked what makes the KB kit work so well, Grissom explained how the Kenny Brown-designed K-member promotes more positive caster, allowing less aggressive initial negative camber. In other words, instead of running 3 or 4 degrees of negative camber like most Mustangs, 0.75 degrees of negative camber produces the same results with less tire wear.
As Kenny Brown puts it, "It's not rocket science, but it is science." Years of experience, testing, and technological advancements have put KB at the forefront of chassis and suspension technology. Brown's philosophy is simple: "The easier a car is to drive fast, the faster you can drive."