As if a stock 412hp Coyote 5.0-liter wasn't enough, Eibach bolted on a Roushcharger 2.3-liter TVS. This definitely required custom tuning from modular tuning ace Adam Montague at ST Motorsports, as Roush specifies its kit is for manual-trans cars only. Adam's main thrust was driveability, and he did a good job in a limited time with the car, although with more time he could smooth the off-idle transitions a bit more. There was no boost gauge, but clearly it was a street tune for 91-octane pump gas, so the power had to be hovering in the 550-rwhp range or less. But not much less, as this is one strong Coyote.
Also on board was K&N filtration and a Magnaflow exhaust system. It gave the expected Magnaflow civilized rumble at idle and a meaningful bellow when processing the wide-open-throttle supercharged air mass, but the vast majority of the time it was drowned by the annoying howl coming off the worn set of tires.
Put all these parts together and you have one fun Mustang. On the street, everyone enjoyed the flat cornering, minimal brake dive, and general overall competence of the new Mustang. The steering is especially nice--no doubt aided by the tauter suspension--and it was singled out by several drivers for its precision and feel. We noted a firmer-than-stock, but by-no-means-harsh ride.
We began with the shocks adjusted to their softest settings, which was pretty cush around town and when cruising, the minimal trade-off being a slight under-damped feel over big heaves or when beginning to hustle over bumpy roads (which we now have plenty of in California). Considering the short sidewall rolling stock, we thought the ride was great for a lowered, stiffer car. The suspension was quiet, with no knocks or squeaks.
Later we sampled the shocks on their mid-settings on the street and liked it best. Ride harshness was barely elevated, but the odd under-dampened pitch was mainly gone. We also got a rude surprise when positively hammering on the throttle on a back road. With the shocks at their softest, we hit a big hummock in a fast corner and the front end bottomed and took a quick heart-in-the-throat step outward. That was a lesson to keep things sane when the shocks are adjusted softly.
Did we mention this thing has a ton of power? The combination of auto trans and blower torque made little squirts of power nearly irresistible and super-easy.
Rear braking is stock and...
Rear braking is stock and good. The BFGoodrich g-Force KDW tires measure 265/30ZR-20 front and 285/30ZR-20 rear, but were already dog-tired by the time we sampled them.
Eibach's R1 shocks adjust...
Eibach's R1 shocks adjust using the provided wire tool. The fronts are super easy, adjusting from the top of the shock as shown. The rear adjusters are accessed through a window in the bottom shock mount and take a little practice if the car is on the ground. Raised or with the wheels off, the rear adjustment is super easy. The adjusters have click detents, so it's easy to keep track of adjustments.
If the blower didn't have...
If the blower didn't have Roush on top of it, we'd swear it grew there at Ford's Flat Rock plant. The Roush blower adds a little over $6,099 retail to the project, and is rated by Roush at 540 hp and 465 lb-ft at the flywheel with 9-10 psi of boost. It's interesting that the engine coolant is now red and the charge coolant is green.
Our track day was a modern classic. The ease with which a car such as this can transform into a track-friendly bruiser is a real mind-blower to anyone who lived through the old days. We eyeballed everything on the Speed Ventures self-certified tech sheet, checked the oil and coolant levels, put a torque wrench on the lug nuts, filled the tank with 91 octane, put on a helmet, and rolled onto the roval at California Speedway in Fontana, California.
This is an infield road course and about half of a super speedway oval, and in the long front straight and heavily banked turn there is plenty of speed to test your manhood. Luckily for us, we were on Ford's 145-mph speed limiter by the start-finish line, and so got to bubblefoot it through the banking. That's a good thing in a car without a rollcage, proper racing seat, five-point harness, or head restraint--believe us. We tried the softest, mid-range, and firmest shock settings and definitely enjoyed the firmer settings. We actually turned the fastest lap time by an insignificant margin on the mid-range settings, but preferred the firmest settings for track use.
Fontana is a smooth track, save for right before entering the oval section. Here the infield course is sometimes routed wide over perpendicular service roads, and this was the only place we wished for more suspension control. Actually, what we needed there was a Trophy Truck suspension, so it's hardly a meaningful complaint.
We did not adjust the sway bars. These can make a huge difference, but the car's balance was good, time was limited, and we were most interested in the shocks. We've found that adjustable sway bars are a big help in setting up the car the way you like it, and require no further adjustment unless meaningful changes in weight or power take place. We liked what we felt, knew we were close to optimal on the bars, and left it at that.
Big kudos to the Brembos, too. The first session brought on a light softening of the pedal, but once we let the brakes cool in the garage between sessions (one heat cycle), they were strong and consistent the rest of the day. Braking a 4,000-pound car from 145 to 25 mph every two minutes, followed by three more hard brake applications in-between, will uncover any brake weakness. And we didn't find any.