Methanol Racing at IHRA
by Bob Szabo
IHRA DRM - 2006 Issue #22
Methanol is a very popular fuel at many IHRA events. It is the fuel of choice in supercharged Pro Mod (low 6 sec., 220+ MPH), Top Alcohol (high 5 sec., 240+ MPH)l, and several of the faster bracket classes that run in the 8ís, 7ís, and 6ís. Those include Erson CamsTop Sportsmen, Mallory Top Dragster, and Accel Quickrod. It shows up in many of the other classes from time to time as well. Those are the eMax drag racing series Box & No Box ET racing and occasionally in Lakewood Super Rod and Hurst Hot Rod. Methanol costs less than racing gas, although, approximately twice as much is used. Many other advantages are provided such as cooler burning with a wide tuning air to fuel ratio tolerance. However, corrosion and aldehyde exhaust fumes are undesirable perils. Several IHRA racecars with methanol setups are featured. Various aspects of methanol are discussed with the photos.
note: photos coming soon
photo-1 Larry Higginbottham's using his favorite tool on his potent Top Sportsman '96 Corvette with a 526 cubic inch, blown alcohol Big Block; running a special 3 speed automatic transmission based on the turbo 400. Higginbotham qualified at Norwalk with a 6.43 at 209 MPH; what a run for a full-bodied drag racer. Larry is making a secret adjustment, caught with our spy-cam. Donít tell him.
photo-2 One of Mike Manners' blown alcohol Accel Quick Rod 8.90 second bracket dragsters. Mike qualified at over 200 MPH in his powerful methanol supercharged entry, at the event for this photo.
photo-3 The Tony Rubert Competition Top Sportsman 540 Big Block '80 Malibu Racecar runs 7.517 at 186+ MPH with blown methanol. Blown alcohol engines have a loud cackle in the exhaust pipes. They are a crowd pleaser at most events.
photo-4 The SummitRacing.com Pro Mod '06 Dodge Stratus of Steve Bareman runs a 526 cubic inch late model Hemi on methanol. This supercharged entry runs a 14-71 Roots supercharger at 20% overdrive or about 650 cubic inches of air per revolution; buzzing to about 9,000 RPM in each gear; or a rate of about 3,400 cubic feet a minute (CFM). Forward of the race engine is a 44 primary ampere magneto by MSD. Running at 2,700+ pounds of racecar weight with driver, this engine combination makes around 2,500 horsepower. The tubular frame around the blower belt protects hood and fenders in the event of a blower belt failure. The blower belt consumes several hundred horsepower to drive the blower to over 12,000 RPM.
photo-5-Jody Graham's Top Dragster runs supercharged methanol in a 526 cubic inch Chevy; with a now traditional high flow injector. Graham ran 6.65 seconds at 199 MPH at Norwalk. Roots supercharger with methanol has a very wide tuning range, runs cooler than gasoline, and is easy on parts when it is adjusted properly with reasonable maintenance. Roots blown methanol engines, built with the latest parts, can last a season with little breakdown. Power levels over 1,600 horsepower are really easy to achieve. Levels approaching 2,000 horsepower are also within reach, with a little more supercharger overdrive and high flow cylinder heads.
photo-6-Bob Bellamyís IHRA ET dragster with unique tunnel ram and a mechanical fuel injection hat on this normally aspired race engine. This setup is proving to be advantageous in normally aspirated applications. The throttle hat assembly traps the air above a plenum. The plenum provides a unique reservoir for the ram tubes. The plenum has a specific minimum volume requirement. The plenum connects to the tunnel ram tubes. The tunnel ram tubes join the intake port for a specific volume of air and fuel that fills the cylinder for each intake valve event. With the proper size plenum and intake tube/port volume in relationship to the cylinder, very high volumetric efficiency can be achieved yielding high horsepower. Intake combinations such as this can make 600 to 1,000 horsepower from a small block engine in different stages of tuning from less expensive and lower RPM to more expensive and higher RPM setups.
photo-7-Ethanol versus methanol in a Funnycar battle, in front of a pumped up IHRA evening racing crowd, between Mark Thomasí Ethanol Performance í06 Monte Carlo and Thomas Carterís Jawbreaker í05 Camaro. Alcohol Funnycar rules specify a maximum 14-71 Roots supercharger; and are typically run at 50% overdrive for 14,000+ RPM blower speed. Intake manifold temperature is a critical measurement with high overdrive applications such as this. If excessive manifold heat occurs, it is responsible for a dramatic loss in performance. Tuners use ignition retard and/or fuel system enrichment to aid manifold temperature control. Some of the methanol dissociates into other compounds during blower boost (if so equipped) and engine compression. That results in combustion of methanol and the other compounds. Intake manifold temperature has a big effect on the amount of dissociation and the resulting tune-up to compensate.
photo-8-racerís bin of various methanol pistons with melted domes and other heat damage. The top of this piston shows a sunken pocket from the top (left side in photo) through the valve clearance pocket. Further heating would have resulted in melting a hole in the piston, burning the wrist pin, and the connecting rod. Some pistons can be burned so badly that the crank case oil is ignited from the burning combustion that is piercing the piston dome. While methanol has a wide tuning range, many teams run it at an air to fuel ratio lean limit. Occasional piston dome melting such as this is the peril. When it occurs, often the upper ring land is collapsed around the upper piston ring. The result can be a scuffed cylinder. Pistons from this team were available at an IHRA national event as souvenirs. I imagine every failed part from a drag racecar has a story: a big win or a big loss. I had a few through the years figuring out normally aspirated and blown methanol race engine combinations.
photo-9-Alan Leeís Hot Rod 8.9 second eMax Series, Accel Quick Rod 23 T bodied roadster with 468 Big Block running a stunning stack fuel injection. Stack length determines the tuning RPM for peak power. Stack volume with port volume should exceed cylinder volume for proper cylinder fill during intake valve opening. This combination of the Nostalgia T body with the open stack fuel injection and eight polished exhaust pipes makes one of the most vivid racecars for the public view. Could Alan let us know if the flames on the body ever go out!
photo-10-Potent Small Block with Ronís fuel injection throttle body on perfected single plane, tall manifold. One of the biggest evolutions in drag racing was cylinder head porting matched and coordination with optimum intake manifold development. Methanol works with combinations such as this fuel injection setup on a carburetor manifold, or with a methanol carburetor conversion on a carburetor manifold. Several highly competitive IHRA racers use either a carburetor (one or two) or fuel injection combinations. Methanol in either runs very well.