Motor & Drivetrain
Darryl streamlined the exhaust flow with Lemons 2-inch primary pipe headers and 3.5-inch collectors that neck down to a 3-inch stainless exhaust tubing interrupted by Flowmaster Super 44 muffs. Otherwise, the engine is untouched. He included a GMPP accessory drive system, computer harness, et al that depends wholly on a Kinetik high-performance battery. Would Yenko have included the dry sump oiling system? You bet, red rider. Darryl made it all work with Peterson Fluid Systems equipment and the LS7 oil tank and ancillaries. Engine coolant is cycled and managed by a Be Cool radiator and twin push fans. Though the 427 is factory rated at 505 hp at 6,300 rpm and 470 lb-ft of torque at 4,800 rpm, Darryl figures the underrated engine makes more like 540 hp in a 3,300-pound envelope. However, for the roll-out, the engine was saddled with less-than-optimal LS3 exhaust manifolds with pre-cats and cats and four oxygen sensors. The immediate future will include slicker LS7 manifolds for the full-on green conversion and Darryl is working on that with GMPP right now. Despite serious wheelspin, drag testing revealed 12.50-second elapsed times at 118 mph, more or less confirming his power guesstimate. A sticky tire would shove this job straight into the mid 11s with nary a drop of sweat or blood. Lucky guy got the first Tremec T56 Magnum transmission ever built, worthy of at least 700 lb-ft. He put an LS7 flywheel and clutch assembly behind it, collaborated with Shafi Keisler on his conversion package for the bellhousing and hydraulic linkage, whipped up a driveshaft, and hooked it to the Moser 12-bolt (33-spline axles).
The theme is green. Undoubtedly, there's some recycled steel in the brand-new repro Dynacorn body provided by Classic Industries. The paint is therefore water-based, in this case, PPG Silver Ice Metallic stolen from the '10 Camaro palette. OER provided every bit of the exterior trim, including the Yenko badges, ZL2 replica hood, and the Z/28 spoiler. As you can see, D&P spent many hours perfecting the surface of the metal.
Since this exercise was more about fitting modern power to an older vehicle, the Yenko tribute's interior looks pretty much like it would have in 1969. OER supplied Darryl with a COPO 140-mph speedo, a Z/28 tachometer, and no less than 224 additional trim and working parts. Since the stock seats are flatter than boards and would slide you right out the door if they could, Darryl specified Pro Car seats. Stitchcraft Custom Interiors in Westminster did up the buckets and the bench seat to match. As a real road car, HVAC was mandatory, in this case a Vintage Air system. Tunes? He's got 'em. A full-on, though discreetly placed, system winds from a Clarion stereo head through Kicker speakers. He put a Line-Loc on the Hurst shifter poking from the repro console/gauge pack just as it would have been in the old days.
Here, DSE rules. The key to this car's handling and suspension changes is the subframe which is designed around C6 Corvette spindles. The front package includes the rails; rack steering; modified steering knuckles; Delrin bushings; tubular upper and lower control arms; coilover shock absorbers; a hollow, 3-piece, 11/4-inch splined anti-sway bar; and solid aluminum body bushings. Marching to the rear, we find DSE mini-tubs bookending DSE's QUADRA Link suspension, Koni aluminum-body adjustable coilover shocks, upper shock mount crossmember, Panhard bar, and high-durometer bushings rather than Heim joints. Darryl tied front to rear via subframe connectors.
Wheels & Brakes
Darryl designed the D&P wheels specific (as yet to be named) and paired them with BFG KDW 2 rubber. The 18x8s carry 275/35s while the big, back 12-inchers sling 335/35s, thus ensuring a maximum contact patch. The dark centers aptly promote the Baer Pro-Plus braking system with 6P calipers and 14-inch plates at all corners. ABS Power Brakes in Orange, California, supplied the master cylinder and matched it with a special accumulator.