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Installing an Exhaust System and Headers - Project Hardtop Hellion

Basket Of Snakes - The Headers and Exhaust System of the Hardtop Hellion

Jake Amatisto Mar 17, 2014
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We had several different options for the exhaust system and headers on our 1963 Nova project car. We looked into everything from mild, shorty header/chambered muffler combinations, to ultra-loud header collector/turndown setups, but eventually decided on a setup that fits somewhere in between. Since this car was built to be a rowdy street machine, quietness is less of a priority than horsepower, so we wanted headers with the largest primary tubes possible and a 3-inch diameter X-Pipe (no tail pipes due to limited space over the axle). Unfortunately there aren't any Chevy II kits out there that fit those criteria; however Hooker Headers and Flowmaster had exactly what we were looking for.

As for headers, there are a few styles available for the '62-65 Novas, including full-length (downswept), shorty headers, even tri-Y's, but the largest bolt-on header you can get is the classic fenderwell header design. Fenderwell headers are the largest because the primary tubes don't have to squeeze between the frame rail and engine block, so instead of a 1-1/2 or 1-5/8-inch primary tube, you can fit 1-3/4-inch primary tube with a few sacrifices, of course: the power brake booster, factory brake lines, and rear portion of the inner fenders. Hooker's Super Competition Fenderwell headers (PN2214HKR) were the perfect choice.


For pipes, Flowmaster's Scavenger Series X-Pipe kit and collector extensions were ordered, as well as a pair of Pro Series 3-inch Laminar Flow mufflers. The X-Pipe reduces harsh tones, while balancing exhaust pulses. The Pro Series mufflers we chose are a round case design that houses two facing resonators that are wrapped in a sound-absorbing material. The result is a great, powerful sound but tame enough for the street.

To put the exhaust system pieces together we contacted Lee Watts at O.C. Muffler Man in Placentia, California. Lee and son Jake are custom exhaust system experts and have worked on many magazine projects over the years, so we knew our Hardtop was in good hands. Since our setup is a bit unconventional, considering how low the car is and piping size, it made sense to have a professional weld it together and we're glad we did. Typically, early Novas run side pipes with no cross over; we aimed to try something different.


Part Numbers



Part number

Flowmaster Collector extensions SF300
Flowmaster Pro Series Mufflers 13016101
Flowmaster Scavenger Series X-pipe kit 815933
Hooker Headers Fenderwell headers 2214HKR


Installation of the fenderwell headers starts with the removal and eventual relocation of the factory brake lines. The exhaust tubes will actually route through the area of the inner fender where the factory brake fittings are mounted.


The bottom part of the fender you need to remove is spot welded to the frame. We found that an air chisel worked best for detaching it.


After drilling out the corners with a hole saw, we started to make the cut with a large electric Sawzall, but it was too violent and we ended up using the small air reciprocating saw. It took a while, but the cuts were much cleaner.


After spray-painting inside of the fender, our headers fit through the new slots nicely.


Our 3-inch header collectors feature a classic 3-bolt flange; Jake Watts handled the welder and welded up our collector extensions.


The Nova’s subframe connector is positioned right where the pipe turns in, off of the collector, which really affected the angle of the pipes. To correct this, Watts was able to compress the 3-inch pipe into an oval in order to achieve the proper alignment with the remainder of the exhaust.


Unfortunately the cage was built before we had considered how the exhaust would route, so we had to make room for the X-pipe by cutting a bar that we’ll need to eventually reconnect.


Here, Jake Watts positions the X-pipe for welding.


The Pro Series mufflers from Flowmaster are a great choice for powerful street cars. They sound awesome, while taking away a lot of the harshness that a straight-through system typically has.


We positioned the mufflers just before the axle, tucked as high as possible. The Pro Series mufflers actually have what’s called a Cool Case, meaning they don’t get as hot on the exterior so it’s OK to tuck them up.


As you can tell from our exhaust pipe size and muffler choice, shown here painted with semi-gloss hi-temp engine paint, quiet was not something we were after. We wanted something that sounded aggressive, would choke the least amount of horsepower away, all while remaining street legal; we think this setup sealed the deal. We have to mention since our project is currently insulated by a single layer of carpet, you could say the interior drone is more than most would be comfortable with, but it’s not a huge concern of ours. Dare we say we enjoy it?


Hooker Headers
Aberdeen, MS 39730
Flowmaster Inc.
Santa Rosa, CA 95401
The Muffler Man
Placentia, CA 92870



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