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Toyota RF1A Level Up
The gear driven RF1A Toyota transfer case found in 1979-1995 4 cylinder pickups and 4Runners fits the needs of many wheelers. It offers a strong, lightweight package with growing aftermarket support. These transfer cases have been used in numerous pickups, 4Runners, buggies, and even Jeeps! Everything from dual transfer case adapters, low range gear sets, twin sticks, and low profile crossmembers are available for Toyota transfer cases from a bevy of aftermarket sources. The RF1A is lighter and less expensive than a Dana 300, though they are not as easy to “clock” and do not allow front wheel drive operation.

SLICK SLEEPER
Mustangs are usually not candidates for sleepers, because everyone knows Mustangs have plenty of power from the factory for their lightweight bodies. This example, owned by Mike Skiles, looks like an original ’69 Mustang, but as soon as the engine is fired, that logic is thrown out the window.

PLAYING FAVORITES
From Superboats to Bowriders, Here’s a List of a Few of Our Favorite Boats Author It’s one of our favorite pastimes on a rainy day: we sit around and talk about our favorite boat or boats. It could be the first boat you ever drove or even a favorite hot rod you always wished you could have instead of the bowrider or deckboat you use to accommodate your family’s needs. Then, of course, there are the big-time offshore go-fasts that make everybody’s jaws drop. You know which boats have a special spot in your heart. Let’s see how your list stacks up against ours.
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PRODUCT SPOTLIGHT: The ProFlex DXI by Advanced Fuel Dynamics
Maximum Results with Minimum Effort: The Best Flex Fuel Solution for 2020+ GM V8 Trucks & SUVs
Author
The Auto Builder Staff
Photos courtesy of GM and Advanced Fuel Dynamics
Why You Should Be Running E85
E85 isn’t just for race cars. It’s a powerhouse fuel that’s widely available and seriously underrated. Here’s why you should be running it in your GM truck or SUV:
- More Power: E85 has an octane rating of 100-105, allowing for more aggressive timing and higher compression—aka more horsepower.
- Cheaper Fuel: E85 is usually way cheaper than premium gas, meaning you save at the pump while making more power.
- Lower Engine Temps: Ethanol burns cooler than gasoline, reducing wear and extending engine life.
- Cleaner Emissions: Less carbon buildup, fewer greenhouse gases, and a happier planet.
- Detonation Resistance: The high octane rating helps prevent knock, making your engine run safer and stronger.
- Renewable & Sustainable: Made from corn and other biofuels, reducing dependence on fossil fuels.
Advanced Fuel Dynamics: Born from Frustration, Built for Performance
Back in 2014, a tuner got fed up with E85 tunes that never seemed quite right. The problem? Pump E85 is all over the place when it comes to ethanol content, and a fixed tune can’t compensate for that. The solution? A real flex fuel system that constantly adjusts in real-time—thus, Advanced Fuel Dynamics was born. Since then, they’ve been cranking out battle-tested fuel solutions for street, strip, and dyno warriors alike.
ProFlex DXI: The Plug-and-Play Flex Fuel Revolution
Forget everything you know about flex fuel conversions. The ProFlex DXI is the first and only true plug-and-play flex fuel system for the Vortec 5.3L, 6.2L, and 6.6L GM engines. It’s like adding a cheat code to your truck or SUV—more power, better efficiency, and the freedom to run E85 or pump gas whenever you want.
Why the ProFlex DXI is a Game-Changer:
- All-In-One System: Everything you need to run E85, no extra parts required.
- 100% Dyno-Tested: Guaranteed performance, durability, and reliability.
- Patented DXI™ Technology: Real-time fuel adjustments with a 30-millisecond refresh rate, keeping your engine happy no matter what’s in the tank.
- True Flex Fuel Capability: Run gas, E85, or anything in between—seamlessly.
- Better Injector Management: More power and better efficiency on both gas and ethanol.
- Zero Tuning Required: Works with your stock ECU, so no trips to the tuner and no warranty worries.
- Half the Cost of Tunes: No expensive ECU unlocks or dyno sessions needed.
- Cleaner Emissions: Runs cooler and burns cleaner for a more efficient engine.
- Race-Grade Fuel, Pump Gas Price: E85 is high-octane and dirt cheap.
- Bolt-On Friendly: Works with power adders and other performance mods.
- FlexLink Compatible: Add the FlexLink module to monitor ethanol content live on your smartphone.
- Cold Start Plus™ Tech: No more hard starts in cold weather—fires up like a champ.
- Instant Response: No delays, no lag—just pure, real-time fuel management.
The Easiest Flex Fuel Upgrade You’ll Ever Do
No tuning. No special tools. No weeks of downtime. The ProFlex DXI is the simplest, smartest, and fastest way to unlock flex fuel capability in your GM V8 truck or SUV. Whether you’re after more power, lower fuel costs, or just want the ability to switch fuels on the fly, this system delivers.
To learn more and get your own Proflex DXI, haed on over to the Advanced Fuel Dynamics website today!
ARTICLE SOURCES
Advanced Fuel Dynamics
Performance Flex Fuel Systems







