Bullnose Bill Answer
by Ed

What upgrades are needed for a 1984 F150 when swapping to a 302 or 351 engine?

Bullnose Bill explaining engine swap options for a 1984 F150.

This Q&A session is powered by Bullnose Bill, Bullnose Garage’s advanced AI mechanic.
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Bill says:

Hey there! Sounds like you’re planning an exciting swap. Let’s dive into what you’ll need to consider for dropping a 302 or 351 into your ’84 F150.

Transmission Considerations

Your truck currently has a 3-speed manual with overdrive (probably the Tremec RTS or similar). Both the 302 and 351W (Windsor) can bolt up to your existing transmission bellhousing. However, the clutch and flywheel may need attention:

  • Flywheel: The 300 I6 and small-block V8s (302 and 351) use different flywheels. You’ll need a flywheel that matches the engine you choose.
  • Bellhousing: If your current bellhousing fits the small-block pattern, you’re in luck. If not, you’ll need a V8-compatible bellhousing.
  • Clutch: Make sure your clutch matches the flywheel and engine torque. Going from an I6 to a V8 might necessitate an upgrade for durability.

Engine Mounts

You’ll need V8 engine mounts. The good news is that they should bolt right into your frame, as the mounting points are the same between the I6 and V8 models.

Rear End and Driveshaft

The existing rear end should handle the power increase of a 302 or 351, assuming it’s in good condition. Here’s what to check:

  • Rear Axle: The 8.8-inch or 9-inch rear ends found in these trucks are robust, but it’s wise to ensure the gears and differential are in good shape.
  • Driveshaft: You might need a different length driveshaft, especially if any transmission changes are required down the line.

Cooling and Exhaust

Don’t forget the ancillary systems:

  • Radiator: Consider upgrading to a V8 radiator for better cooling capacity.
  • Exhaust: Get a V8 compatible exhaust manifold or headers and exhaust system.

Electrical and Fuel System

You’ll have to tweak these systems:

  • Wiring Harness: The wiring for the I6 may not match up perfectly with a V8. You might need some customization or an aftermarket harness.
  • Fuel System: If you’re switching to a carbureted setup, make sure the fuel delivery system is up to par with the V8’s needs.

This swap is popular and well-documented, so resources are out there to help guide you through the process. There might be a video on the Bullnose Garage YouTube channel that breaks down a similar swap. Also, hit up the Bullnose Ford subreddit for community advice. Good luck, and enjoy the project!

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This answer was written by Bullnose Bill, our AI shophand trained on hundreds of Bullnose-era Ford topics. He knows his way around old Ford Trucks.

As with all of Bill’s answers, it has been reviewed and approved by Ed Zenisek, the man behind Bullnose Garage and a real human being.

While we do our best to keep things accurate, always double-check any repair advice and use proper safety procedures. For real-world walkthroughs and more hands-on content, check out Bullnose Garage on YouTube or visit the BullnoseFord SubReddit.

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