A Nice listing of all the great features of the 8.1 496 engine. We had a chance to get two from a Sheriff Patrol boat that required them to be replaced at a certain hour mark. Back when the 8.1L was being developed, we, with a friend named Mark McPhail, really looked hard at making a carbureted aluminum intake for this engine. You stated the major problem: The No. 7 intake runner is going straight at the distributor location, and since the inlet ports are symmetrical (all the same design), the No. 7 runner is pointed toward the flywheel of the engine, not toward where a carburetor would be mounted! They can get away with it in a fuel-injected, dry-flow design. But when you add fuel to the mix and try to make turns like that, you have real distribution problems that cannot be overcome.
Yes, Raylar Marine has released the BigPower aluminum cylinder heads, which also are accompanied by a new shorter-runner, large-plenum, fuel-injection manifold. The complete package for the 8.1L GM marine engine picks up right at 100 hp! It also kicks your credit card to the tune of $6,000. This puts the power up to 525 hp. Now that would be a nice-running dualie Crew Cab!
What you're doing with your engines is a perfect application. They will motivate your street rods with a ton of torque and burn the tires as long as you wish to keep your foot in the throttle. Sorry we don't have better news. And yes, it's a crying shame that we don't have a use for these engines.Source: raylarengine.com
Q I was wondering if you guys have heard about Pulstar spark plugs. I saw an ad for them claiming substantial gains in horsepower, torque, and mileage. I checked out the website, and they were $25 a pop. I have a '92 Camaro and a '93 K1500 (both with 350 TBIs) and was thinking about trying them out. It would be awesome if you could do an article with some dyno results in a few engines/cars. Thanks.
Ryan Telenga Oak Harbor, WA
A OK, guys and gals. This is how we usually get into trouble with our answers. What Pulstar is doing is basically putting a condenser into the spark plug to store the collapsing energy at the end of each firing cycle. This energy usually just travels back up the plug wire toward the open cap or coil in whichever arrangement your ignition is. This stored energy is added to the next firing cycle and increases the available energy.
Back at the end of the 1991 season, the NHRA Top Fuel cars were on the brink of running 300 mph. The problem they were having was lack of ignition energy. They could move enough fuel but could not burn it. We were working with Larry Meyer, the crew chief of Tom "The Mongoose" McEwen's Top Fuel car. Meyer had come to McFarland Inc. to pick our brains. One of our electrical engineers had the idea of making a condenser that would fit down onto the Hemi spark plug and be hidden by the valve covers. We built a set of 16 (twin plugs per cylinder) and showed up at the Winternationals in February 1992 with them on the car. McEwen proceeded to set the low e.t. for the race and the top speed of the meet at what we remember to be 299 and change! Unfortunately, the material that we used to make the condensers meant there was a specific amount of time before they would transfer the energy to ground and cause a misfire. We didn't know this until it happened. When Dale Armstrong, then crew chief of Kenny Bernstein's Top Fuel car, saw them, he promptly named them Sparklers. At Gainesville, Florida, that year, Bernstein broke the 300-mph barrier, and the rest is history. The concept has been out there for years and does work if you need the increased spark energy to light the fuel.