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Product Spotlight: Dynamat Xtreme Bulk Pack
If your ride still sounds like a tin can at speed, it’s time to get serious. Dynamat Xtreme isn’t a luxury add-on — it’s a foundational upgrade for builders who want their cars to feel tight, solid, and finished. This is the same material trusted in high-end customs, competition cars, and OE applications for one simple reason: it works.

CHEVELLE MEMORIES
“If these four walls could only talk, what great stories they could tell” is an old adage that is certainly apropos from a historical perspective. In the context that we Americans have an ongoing love affair with the automobile, it could also be said that if a classic car could only talk, it could tell some pretty great stories as well!”

Goodguys Launches Inaugural BASF Legends of Hot Rodding
The first-ever Goodguys BASF Legends of Hot Rodding event brought the heart and soul of traditional hot rodding straight to downtown Nashville, Tennessee, delivering a premium weekend packed with world-class hot rods, customs, live music, and the unmistakable energy of America’s golden automotive era. Held May 15–16 at the newly renovated Fairgrounds Nashville, the all-new event delivered a fresh experience for hardcore enthusiasts while celebrating the roots of the hobby that built hot rodding culture.
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Product Spotlight: Sequential 8-1 Headers by HDR Industries & Stainless Headers MFG. INC.
Dana Harp of HDR Industries partners with Stainless Headers to bring a streamlined, standardized solution to exotic jet boat header builds.
Author
The Auto Builder Staff
Photography by Scott Killeen
Built for Power & Precision
Let’s cut to the chase, because this definitely isn’t your grandpa’s set of rusty old manifolds. The HDR Sequential 8-1 Headers from Stainless Headers are a next-level, hand-crafted performance weapon for big-inch V-8s — purpose-built for jet boat and high-output marine applications — and they were one of the most talked-about exhaust systems as seen at PRI 2025.
These headers don’t just look wild on the show floor. They represent years of refinement, real-world testing, and hardcore fabrication experience from one of the most respected names in the space.
What They Are
These aren’t just headers — they’re a race-inspired, sequential 8-into-1 exhaust system designed and hand-crafted by Dana Harp of HDR Industries, now partnered with Stainless Headers to deliver a more accessible, standardized solution without losing the custom edge.
Dana Harp has made these systems famous over years of building exotic, high-end jet boat exhausts, and this collaboration brings that same DNA to builders who want something beyond off-the-shelf. Available for Big Block Chevy and Gen III/IV LS platforms, these headers deliver bespoke performance plumbing that’s as functional as it is aggressive.
Engineered for Maximum Flow
Forget cookie-cutter designs. The 8-1 configuration merges all eight exhaust runners into a single, unified path, a layout that serious racers and fabricators obsess over for its potential to balance exhaust pulses and maximize flow.
This isn’t theory-only engineering — it’s the kind of design that gives high-RPM engines room to breathe and torque that pulls hard through the powerband. Traditional systems split things up with 4-2-1 or 4-1 layouts. Eight into one is a different level entirely — rare, purposeful, and unapologetically performance-driven.
Premium Build Quality
HDR doesn’t cut corners, and it shows in every detail:
- 304 stainless steel construction with purge TIG welds for strength, durability, and corrosion resistance — ideal for harsh marine environments
- Heavy-duty 3/8-inch header flanges for rock-solid sealing and long-term reliability
- Optional finishes, including ceramic coating, mirror polishing, and custom tip work, allowing you to tailor both performance and presentation
These headers are built to survive real use, not just win points at a car show.
Built for Your Build
One of the biggest differentiators? These headers are built to order. You’re not settling for a one-size-fits-all solution — you’re working from a proven HDR design that can be fully customized to your exact needs.
Tube sizing, collector configuration, port options, O2 bungs, water injection fittings, and custom tip layouts are all on the table. The Stainless Headers partnership makes the process smoother, while HDR Industries ensures the craftsmanship stays exactly where it should be.
Real Talk: Who These Are For
If you’re chasing maximum exhaust scavenging, serious mid-to-top-end power, and a custom-fabricated look that instantly separates your build from the crowd, this is your move. High-end jet boats, extreme marine builds, race-focused engines, or wild custom applications — the HDR Sequential 8-1 Headers deliver both performance and presence.
This isn’t just an exhaust system — it’s a statement piece, equal parts engineering art and horsepower liberator. If peak flow, exclusivity, and real craftsmanship matter, this is how you do it.










