Looks better, sounds better, runs better. What more could we ask? OK, this particular hop-up was a bit pricey at $1,047, but we're really happy with the results. We started with the '31 Model A roadster we tested last month—it's powered by an aggressively average 350 Chevy with typical bolt-ons like an Edelbrock Performer intake, a JET-tuned Quadrajet carb, and ACCEL ignition. The idle was cruise-night lumpity thanks to a single-pattern Lunati cam with 0.457-inch lift and 268 degrees of advertised duration. It ran great, but seemed choked by stock exhaust manifolds and 2 1/4-inch dual exhaust with blown-out turbo mufflers. After 25,000 miles on the combo, the roadster was ready for some more snap.
We took the '31 to the new tech center at MagnaFlow Performance Exhaust and strapped it to the Mustang chassis dyno to reveal a base power level of 207.2 rear-wheel horsepower at 5,000 rpm. After adding Sanderson's 15/8-inch-tube, ceramic-coated shorty headers (PN CC158), a complete mandrel-bent 2 1/2-inch exhaust system, and MagnaFlow's 4x9-inch Wide Open stainless mufflers, power increased to 230.7 at 5,100 rpm. That's a bonus of 23.5 hp, which is more than a 10 percent gain.
The 350 has noticeably more throttle response at all rpm, and more importantly, burnouts are significantly improved. However, it wouldn't be worth it if we hated the way the car sounded. The Wide Open mufflers are just that—straight-through perforated stainless steel tubes with no baffles, louvers, or restrictions. They looked loud, especially in the small size needed to fit the car, and we figured they'd be all blatty and annoying. No way. We were pleased with the mellow rumble at idle, the lack of resonance at cruise speeds, and the shriek of power during acceleration. The sound could be more tame with over-the-axle tailpipes, a crossover pipe, or both. The ceramic-coated Sanderson tubes look far better than the ram's-horn manifolds and the roadster sounds exactly like it should. Combine that with more power to play, and this is a setup we heartily recommend.
