Small Tires, Big Blower:</br> A Carbureted 7-Second Camaro
We Caught Him

Rick Webb is one of those really quick guys who’s hard to catch. In fact, the only reason we were able to bring you this feature as part of our Carbs Only Theme is because he hurt his engine and couldn’t go racing this weekend just past.

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We looked at a number of carb’ed muscle cars to feature as part of the theme and while they were all pretty, none had that indescribable, head-swivelling allure we were looking for. Until we laid eyes on Webb’s blow-through 1973 Chevrolet Camaro RS Z/28

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“What the hell does blow through mean?” you ask. Well, you start with one of these: An obscenely large ProCharger supercharger.

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And you let it cram 30 pounds of boost into one of these: a Holley Dominator that would rather suck its own air than be force-fed. Want to see what that’s like? Watch the video below.

Let’s back up though, because there’s something I need to point out right away.

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Besides being a blow-through car, this is also what you call a ‘small tire’ car. It doesn’t use massive slicks stuffed into huge, hacked-out tubs.

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No, because drag racing is a numbers game, and it’s all about what you can do with certain equipment to be the fastest in your class. Rick races in the True 10.5 division using drag radials. He’s quick to point out that the tires are quite a bit smaller than the Outlaw 10.5 cars which use a 10.5W tire that measures wider and taller.

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It leaves the car with a stance that looks more like a hopped-up street car than a dedicated drag racer. Aesthetically, it’s less aggressive than a pro street car lumpily idling by on a cruise night, but Rick can still go wheels-up and run a low 7-second pass in the quarter – the car’s PB is currently 7.10 at 201.70mph, making it the quickest and fastest small-tire blow-through car in the world.

Tell Us All Your Secrets
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With the six-inch cowl hood removed, we can get a sense that there’s something interesting going on in the engine bay. I don’t see the usual round air cleaner poking up.

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That strange form is actually a carbon fiber Airaid carb hat, which is used to pipe air into the carburetor from a remote location.

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The engine is a 540 cubic inch Dart Big M big block Chevy that Rick carefully built with a combination of race parts that he’s figured out over decades of racing. You can read the complete list of engine specs at the end of the story, but I’ll just point out that the pistons are a coffee can-sized 4.5-inch across.

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The show really starts here, at the 135mm inlet of a ProCharger F3R.

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The supercharger is driven off the crank through a gear drive from The Supercharger Store. It uses straight cut gears like a Winters Quick Change rear axle to adjust the blower’s RPM relative to engine speed. Rick actually finds old Quick Change gears and mills them down to the proper thickness for his setup. Also notice the solid aluminum engine plate.

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From the ProCharger, compressed air makes its way through the firewall and into the cabin.

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Piping is routed back to this water-to-air intercooler mounted where the passenger seat used to be.

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The intercooler is fed by one of these two ice water filled tanks. The second tank cools the engine by pumping cold water through a closed loop system. Who needs a radiator anyway?

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The cooled air charge passes through the carbon fiber carb hat, which is a quarter of an inch thick to handle boost and held down by a large machined nut. Just to make sure pressurized air can’t leak past, the hat is also glued down to the carb base using RTV silicone.

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Rick explained that his success in getting the Camaro to run so hard has been in finding the correct combo of parts. One of the most critical of these coordinated parts is the Holley Dominator carb that’s been extensively modified by blow-through expert Kevin Van Noy at Carburetor Solutions Unlimited.

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CSU completely overhauls carbs to make them blow-through friendly. Long story short, you can’t use an out-of-the-box carburetor and expect it to act right when you throw 30psi at it. For example, a stock hollow float would crush under boost, so CSU used a special closed-cell Nitrophyl float that won’t collapse from the extra pressure.

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Annular discharge boosters with multiple ports were also swapped in to ensure plenty of atomized fuel is on tap to match the enormous amounts of air.

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An Aeromotive fuel pressure regulator runs 8psi at idle, but quickly cranks up to 40psi when the car hits boost. The fuel pressure sensor sends info to a datalogger, one of the very few pieces of tech on board.

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Twin blow-off valves were needed since the ProCharger is so damn big.

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A Dedenbear nitrous timer is coupled with an MSD 7531 progammable ignition to set burnout and launch rev limiters, and also retard timing at specific points during a run to help the car hook up.

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When Rick launches the car, he mashes the throttle and holds this trans brake button until the lights change. When he lets go, the car takes off like a bat out of hell.

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I know that I’ve been focused on the engine this whole time, but this is the Carb Theme after all, and I really enjoyed learning about how a supercharged, blow-through carb setup works. There’s more to making Rick Webb’s Camaro scoot down the track than raw horsepower though.

The Complete Package
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Rick guesses his car makes somewhere in the neighborhood of 1800 to 2000 horsepower, which points us to the biggest struggle when trying to get down the track. Traction.

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Surely larger tires would help, but racing in a True 10.5 class requires a relatively small drag radial. This is where the challenge (and fun) comes in.

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It seems the final piece of the hook-up puzzle was the torque converter, which was recently sorted by Hughes Transmission. They not only supplied a built 2-speed Powerglide, they also worked with Rick to create a custom converter that stalls at 4,500rpm. Isn’t that where you would normally shift a big block?

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Not this one. It revs to a stratospheric (for a rat motor) 8,200rpm.

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Entering the traps at 200mph calls for a parachute.

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Rick has done his best to improve the Camaro’s aerodynamics. Here you can see the chin spoiler he made to match the rest of the fiberglass front end components.

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There’s also a wing tied into the rear of the car, adjustable of course, and fabricated in house.

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The chassis has been stiffened with a certified mild steel rollcage, all built by Rick and his buddies.

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Obviously the first task for the cage is to protect the driver.

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It’s also useful for tying everything together on a unibody car like a Camaro.

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The rear suspension, like the rest of the car, is purpose built and dialed in. The Strange 9-inch rear axle was reinforced with a large steel brace and fitted with 40-spline Moser axles. The True 10.5 class also allows for a ladder bar rear suspension which affords more adjustment than a traditional leaf spring setup.

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We were fortunate to catch up with Rick on a day that he wasn’t either wrenching on the car or trailering it to his next race. In fact, he blew the engine up something spectacular last time he had it out, so it was his misfortune that even allowed us access to the car on a quiet Sunday afternoon.

We would like to thank Rick for rushing to button up the engine and haul the car out to a suitable shoot location, and also for patiently teaching us all about how a supercharged, blow-through carb, small tire drag car works. We want to see a burnout next time!

Keith Charvonia
Instagram: SpeedhuntersKeith

Photos by Otis Blank
Instagram: otisblank

Cutting Room Floor
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I remember thinking how much drag racing sucked until I went to the track. What a beast. Great choice.


7.10s on Drag Radials. Oh yeah.


Rad! NO computers, widebands, crank-fires, etc on the next "carb" feature, please :)


just imagining this thing on better tires makes me nauseous . I tip the hat to any one who can build something this spectacular and handle that acceleration also love the carb theme!!!


My god sort of weapon...or monster, have you come across and lived to tell the tale?!
Most badass machine on here to date!


No doubt this build is insane.
It would be very interesting to get more in details about how they tackle the 2 most notorious problems of they blow-through set up apart from the Friendly overhauld and the special closed-cell Nitrophyl float.
So a Carburetor does not understand pressure because it supplies fuel by creating a pressure drop across the venturi. If the carb sees a 2 PSI pressure drop across the venturi, it will supply that much fuel whether you are at 0 boost or 15 pounds of boost. This would cause the engine to run very lean at max boost. Is he running some sort of fuel enrichment?
The second problem is that when you put pressurized air into the carb, it will make the fuel flow in ways that it is not suppose to flow. The pressure will try to crush the fuel float, it's going to want to blow fuel mix out the throttle shaft, or worse back into the fuel line. Soo the special closed-cell Nitrophyl float solve this?


LOL. Since when do you feature rockets on SH?


EhruMejil Long story short involving the pressure differentials, its know'n as 'boost referencing'


cool car....but may i ask WHY?..... seems like an awful lotta work when EFI would would prob get it done faster simpler and make moar powah...IDK just my 2c.


I've always liked 2nd gens the best, and this one is no exception. Great photos too!


Air seal throttle shafts will keep fuel from running to low pressure areas. Also adjustable fuel pressure regulator will increase fuel pressure to open needles at a higher pressure by using an electric pump that is set to 8 psi rising with the boost pressure 1 to 1.


Cool story. The joke about 4,500 big block shift point was a little corny. I would say, the sound of a big block in the 9,000-10,000 range is pretty sweet. Fast on little tires and that much weight takes a lot of effort and smarts. Keep it up.


@Matt Sure it is, but what's the stock redline for a big block? It takes a built motor to rev that high.


LavarBowers Some people like a challenge!


@Cano Preeeeettty good.


The small tire freak shows are my favorite form of drag racing... I hope to build one someday...even if its for someone else... 

One question sure the cage isnt Chromoly? pretty sure they wont cert mild steel after 7.50..


@chris chabre The owner said it was mild steel so I took his word for it. :)


Glad to see a badass prostreet car finally make it onto speedhunters!


KeithCharvonia well he would know haha. Id love to see more small tire 10.5 cars...


Talk to the blow thru carb god at csu..He knows all and builds all our high hp carbs in az...
It uses boost reference pv's...
And fuel regulator adds 1 psi of fuel for every 1 psi of's pretty simple actually


I guess you could call this a sleeper as well, awesome car.

Chris 'Haffy' Hafner

6.12@244mph on 10.5 radials. That's a car a feature should be done on.


Can we please have more muscle, hot rods, and pro-touring this year. Please?


@zz Yea I want to see the street outlaw guys featured.....


KeithCharvonia Motor like your original MK IV big blocks (chevy) and the 426 HEMI, or BOSS 429, would easily pull 6000-7000 rpm in the 60s. One of the reasons many of them had no warranties.


LavarBowers actually, carbs are fairly easy to make big power with. The fuel metering is metered simply by how much air flows though it - assuming you are running a carb with big enough venturi's, and proper jets. The just aren't as efficient in part throttle/ non extreme ranges of operation like EFI. 

Real world it would probably take more time to tune a custom EFI set-up vs doing basic math and figuring out the right sized carb, then fine tuning it with the right jets to get it reliably running at 8/10 tenths or better performance vs hours of street and dyno tuning for EFI.


That's a badass car true muscle right there


Just wanted to say that was an awesome read. It was good to read more in depth about mechanics i am less familiar with. I feel that the text of an article should explain what can't be seen and i feel this story hits that on the head, 
Thanks very much.


I have a 73 camaro with F3 and blow thru but it's a 400 SBC. I too have then passion Rick does. Ricks car is amazing and give kudos for getting in the 7's with blow thru. Again great article and great car