![\"\"](\"http:\/\/www.stahlheaders.com\/JpgFiles\/m110.jpg\" "\\"Stahl")
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are built off the same jig used to make the headers used on the Penske\/Donohue road race cars from ’68 and ’69.\u00a0 Great ground clearance, with a race-proven design.\u00a0 Fits the theme too…so a good choice?<\/p>\n
Since the primary use of cars like Camaros from 1970 until recently has been drag racing, most of the brand names you think of (Hooker, Hedman, etc.) designed their headers with drag racers in mind.\u00a0 Drag racers don’t tend to run their cars as low as road racers, so they’re less concerned about ground clearance, and low weight.\u00a0 Most headers you find for this crowd are a heavy-ish gauge steel, with a crummy high-temp coating, and hang down 2″ or more below the frame of the car.<\/p>\n
One trait drag racers and road racers have in common, is a focus on the top end of the powerband.\u00a0 As a vast generalization,\u00a0the common\u00a04-1 design SBC header promotes maximum peak horsepower, and the primary tube diameter (1 3\/4″) and collector size (3″)\u00a0most often offered, is really bigger than needed for a typical SBC in most uses.\u00a0 In my case with a 302 (at the small end of SBC displacement) and a focus on midrange (this is an autocross car after all!) – the vast majority of the headers out there just weren’t the right fit for the application, at least\u00a0not as I see it today\u00a0– including Stahl’s headers above.<\/p>\n
My priorities:<\/p>\n
- \n
- Good ground clearance, not hanging below the frame if possible.\u00a0The car will be on and off trailers often.\u00a0 Super low cars with long wheelsbase (108″ remember!) are a nightmare to load and unload from trailers.\u00a0 Plus sometimes we have bumps or dips while racing.<\/li>\n
- Good low-end and midrange.\u00a0 While even in the worst case I should have more acceleration at low engine speeds than the competition (especially now that unfortunately, Terry Fair has wussed out and gone to ESP<\/a>\u00a0with his crazy-powerful 5.0 Mustang), the 3000-4500rpm engine speed range (equating roughly to 30-45mph with initial gearing choices) are what matters, and a lot of people will say the 302 doesn’t even “wake up” until 4500.\u00a0 I’m hoping “those people” are those used to big blocks, who would say that something like an RX8 never<\/em> wakes up… \ud83d\ude42\u00a0<\/li>\n
- Low weight.\u00a0 This weight is up on the nose, and not all that low.\u00a0 Thin-wall stainless like 18ga would be lightest, but also the most fragile in a header-impacting event.<\/li>\n<\/ul>\n
Based on this, I took a plunge on an off-the shelf header that *should* meet these requirements.\u00a0 As with the shifter in the previous post, things aren’t quite right out of the box – the passenger side header needs to be bent downward a bit at the rear, to keep from hitting the floorboard. Might just cut off the triangle flange and go with a v-band, haven’t decided yet. Driver side fits perfectly.<\/p>\n
![\"\"](\"http:\/\/www.rhoadescamaro.com\/build\/wp-content\/uploads\/2012\/06\/P1010354-300x225.jpg\" "\\"P1010354\\"")
<\/a><\/p>\nInstead of a 4-1, it’s a “tri-y” design, also known as 4-2-1.\u00a0 It’s not stainless, but is a thin-wall mild steel, the units are quite light.\u00a0 Primaries are 1 5\/8″, and collectors are 2.5″.\u00a0\u00a0 Those are good conservative starting values, similar to what was used on the engine dyno, though the dyno headers were 4-1.\u00a0\u00a0\u00a0The purpose of the test fitting was to make sure they’d fit the car and its components, before being sent off to Swaintech<\/a>\u00a0for their White Lightning <\/a>coating to be coated inside and out.\u00a0 This stuff is extremely effective at keeping the heat in, I had used it years ago for the turbo components when I took my 240sx to Street Modified:<\/p>\n
![\"\"](\"http:\/\/www.rhoadescamaro.com\/build\/wp-content\/uploads\/2012\/06\/DSC02138-300x225.jpg\" "\\"DSC02138\\"")
<\/a><\/p>\nThis should really help keep the interior heat levels under control.\u00a0 A lot of the restomod\/Pro-Touring guys add a hundred pounds of sound and thermal insulation to their cars…definitely not a fan of that approach for a car with heavily sporting intent.\u00a0 Will probably be doing Swain on the rest of the exhaust system (which itself is still somewhat TBD) to help keep the floor cooler.\u00a0<\/p>\n
From inside the engine compartment, passenger side-<\/p>\n
![\"\"](\"http:\/\/www.rhoadescamaro.com\/build\/wp-content\/uploads\/2012\/06\/P1010343-300x225.jpg\" "\\"P1010343\\"")
<\/a><\/p>\nNot much going on over there, especially with no heater.\u00a0 The Swain will help keep the starter from getting cooked, and not working on a hot engine\u00a0on a hot day.<\/p>\n
Driver’s side is a lot more cramped, but they fit well, with at least\u00a0~3\/8″ clearance to the other hard parts.\u00a0 Again, counting on the Swain coating to help keep the PS fluid from boiling, or other things from melting.<\/p>\n
![\"\"](\"http:\/\/www.rhoadescamaro.com\/build\/wp-content\/uploads\/2012\/06\/P1010347_2-300x225.jpg\" "\\"P1010347_2\\"")
<\/a><\/p>\nGround clearance – not perfect, but close to it, for this car.\u00a0 The larger diameter things have a harder time staying tucked up like this.<\/p>\n
![\"\"](\"http:\/\/www.rhoadescamaro.com\/build\/wp-content\/uploads\/2012\/06\/P1010385-300x225.jpg\" "\\"P1010385\\"")
<\/a><\/p>\nIf I end up with the nice-to-have problem of too much low-end and midrange torque, such that throttle modulation is impossible and the 265 street tires are constantly being blown away… then I might consider going to a more top-end-centric header design, as an archaic\u00a0sort of traction control.\u00a0 Or, if the power feels\u00a0lacking somewhere, having someone like Burns Stainless<\/a>\u00a0design and build a custom super-thin stainless set of headers based on all the engine parameters, with a focus on beefing up the spot of the powerband that feels lacking.\u00a0<\/p>\n
I’m hoping\u00a0the SBC\u00a0have been around long enough, the unit I have is an effective design, taking into consideration its\u00a0apparent goal of being a good “street” header.\u00a0 I had Burns do a full workup years ago for my 240sx when it was in STS (stock engine, normally aspirated) and the tubing diameters and lengths their software spit out, were pretty much exactly what DC Sports had put together in their cheap off-the-shelf unit.<\/p>\n
Now that I’m confident these things are going to fit, placed an order for the rest of what needs to go under the hood.\u00a0 Hope to get the flow of updates coming more regularly soon.<\/p>\n
- Low weight.\u00a0 This weight is up on the nose, and not all that low.\u00a0 Thin-wall stainless like 18ga would be lightest, but also the most fragile in a header-impacting event.<\/li>\n<\/ul>\n
![\"\"](\"http:\/\/www.rhoadescamaro.com\/build\/wp-content\/uploads\/2012\/06\/P1010374-225x300.jpg\" "\\"P1010374\\"")
<\/a><\/p>\n