While its prime motivation...
While its prime motivation these days is to sell parts, UPR actually started out as an install shop. These days there is still have a small shop on-site to test-fit parts and work on in-house project cars. Jeremy had the car up in the air and ready to rock when we arrived.
Last we left Lethal Performance's '11 Mustang GT project car, it had laid down 700 hp at the tire and clicked off a 10.33 at 133.68 mph. At the time, hot shoe Jeremy Martorella of UPR Products fame felt that traction was holding the car back from making the most of its newfound power. It's not a huge surprise that hooking up 700 rwhp is a challenge, even on Mickey Thompson ET Streets. Of course, doing so with a stock suspension can make that task even more difficult. The fact is, these days adding massive horsepower is relatively easy. In ye olden days we could focus on power bolt-ons for a while, and then wait to get around to addressing our Mustangs' other areas. Today we can add instant horsepower and then we have to play catch-up.
"The Coyote has amazed me. It's one thing for a manufacturer to release a 400-plus-horsepower street car, but what you can achieve with the Coyote is unheard of," Jared Rosen of Lethal Performance enthused. "In years past you would have spent over $10,000 on a stroker, blower, and fuel system to achieve what we have with bolt-ons. We've seen over 500 hp with naturally aspirated bolt-ons, and over 700 with power adders. It is simply amazing!"
Sure, the chassis and suspension of modern Mustangs is far more in control than it was during the Fox era, but they are clearly biased toward handling. The stiffer chassis helps a lot, but when it comes to the dragstrip, you'll still be fighting wheelhop and traction. This is especially true if you're banging gears in a manual-trans car.
So to whittle down the e.t. of its project car, Lethal Performance turned to UPR Products for a rear-suspension revamp. Since test driver, Jeremy Martorella, works at UPR, he was able to work up just the right combination to dial in the hook.
"The factory three-link design works wellùthat is, until you hit it with 700 plus horsepower. The factory/rubber bushings have so much deflection, it's hard to make tuning changes as the suspension is inconsistent," Jeremy explains. "We saw as much as a tenth and a half change from run to run with the factory arms. The fact that the Coyote manual transmission has a 3.66 First gear ratio makes it even more of a challenge. By adding the UPR Pro Series kit, we have changed from the factory rubber to an adjustable Heim-joint-style suspension."
And dial it in he did. After adding this new suspension, the car's e.t. dropped to a 10.20 at 134.85 mph, and the 60-foots dropped from 1.45 to 1.41 seconds.
"Not only is the suspension able to handle 1,000-plus horsepower," Jeremy explains. "It's easy to tune and much more consistent. After the install, our 60 times improved over a tenth, and all runs were within a few hundredths. The addition of the Pro Series kit will now allow us to tune consistently and experiment with launch rpm and gear ratios."
Step one is getting the wheels...
Step one is getting the wheels and tires out of the way. UPR’s Jeremy Martorella made quick work of this with the air gun. Just be mindful of those lug nuts. Even the smallest burr can cause a nasty cut if you aren’t wearing gloves.
With the rearend properly...
With the rearend properly supported, Jeremy began by removing the stock lower control arms. The stockers were obviously designed to suppress noise, vibration, and harshness rather than maximize traction. The replacement UPR pieces are built from chrome-moly and feature Heim-joints, so they improve response and eliminate wheelhop.
With the rearend properly...
With the rearend properly supported, Jeremy began by removing the stock lower control arms. The stockers were obviously designed to suppress noise, vibration, and harshness rather than maximize traction. The replacement UPR pieces are built from chrome-moly and feature Heim-joints, so they improve response and eliminate wheelhop.
All of the UPR bits installed...
All of the UPR bits installed on Lethal’s project ’Stang are double-adjustable. However, don’t get too crazy with adjustments at the outset. Stock length is always a safe starting point for any aftermarket control arm. Here Jeremy measures the stock control arm, then adjusts the UPR Pro Series heavy-duty adjustable lower control arms to the same length. After measuring them, Jeremy slides them over the stock fasteners in the stock arm to ensure a smooth fitment.
Once adjusted to the stock...
Once adjusted to the stock length, the UPR control arms are a direct replacement using the stock fasteners. Jeremy likes to tighten the bolts by feel, saying that torquing the UPR arms to the same specs as the factory arms will cause them to bind. If you are OCD about torquing things, you’ll want to try for 120 lb-ft.
If you just jumped up to the...
If you just jumped up to the latest Mustang, you might be unfamiliar with the upper link’s mounting arrangement. One of the mount’s fasteners is actually inside the car, so you have to pop out the lower seat cushion and remove the nut from inside the car. From there you can move back underneath to continue the process.
Like the lower control arms,...
Like the lower control arms, the UPR Panhard bar is adjusted to the stock length by Jeremy. From there, it’s a direct replacement, just like the chrome-moly Panhard brace that supplanted the stock brace on Lethal’s car. The UPR brace and bar are made from 4130 chrome-moly tubing, so both are durable and lightweight.
After removing the stock upper...
After removing the stock upper mount, Jeremy replaced it with the heavy-duty UPR mount using the stock fasteners. Constructed of 1/4-inch-thick steel, UPR’s Pro Series upper mount is far more rugged than the stock mount, thus better-suited to withstand the rigors of the dragstrip in a Whipple-blown ’11 5.0.
As you can tell by now, most...
As you can tell by now, most of this install is simple remove-and-replace work. However, there is always at least one bump in the smoothest of roads. In this case, it was still an R&R job, but removing the stock upper rearend bushing is quite simply a pain. It basically came down to drilling and hammering it out, but it wasn’t pretty. When it comes to installing the UPR spherical housing bushings, it’s recommended that you freeze the new bushing overnight before you install it. This shrinks the bushing a bit, which eases the ingress.
Here's the completed install....
Here's the completed install. As you can see, the silver-powdercoated UPR bits dress up the undercarriage. This is a nice side effect to adding the stouter rear suspension pieces. Sadly, Ford still isn't painting those rear axle housings, so the rust clashes a bit.
With the new upper housing...
With the new upper housing bushing and upper mount in place, the last step was to install the Pro Series upper arm. Once again, Jeremy adjusted the new arm to match the length of the stock arm, and torqued it to about 85 lb-ft. Featuring a heavy-duty 1-1/4-inch-thick turnbuckle, and a 7⁄8-inch Teflon-lined, chrome-moly Heim joint, the UPR arm not only provides easy pinion-angle adjustments, but it is obviously much stronger than the stock arm. Working in concert with the rugged mount and spherical upper bushing, it obviously eliminates any slop in the rear suspension. By the way, the length of the upper control arm is one of few differences between ’10 and ’11 Mustangs, so don’t try to install an upper arm meant for a pre-’11 ’Stang.
Prior to adding the UPR suspension...
Prior to adding the UPR suspension pieces, Lethal made its first stab at tuning the suspension for the strip by adding these double-adjustable dampers (PN DMU7857P; $370) from QA1. With the completely adjustable suspension on board and Jeremy behind the wheel, the Lethal project 'Stang dropped its 60-foot times by 0.10 second.