Recently, I acquired a 1976 F250 from a farmer’s backyard and it seemed like a good deal at $1,000. The truck had been sitting for a long time, but after tuning it up, it ran pretty decent. I suspected it had a towing package and an EFI engine, but I wanted to verify if it was a 360 or a 390 engine. The difference between the two is the stroke, so I decided to measure it using a simple method that I’m going to share with you.
To determine the stroke, I used a straw and a permanent marker. It’s essential to ensure that the marker stays in the same place during the process to maintain accuracy. The stroke of a 360 is approximately three and a half inches, while a 390 is about three and a quarter inches. I made a mark on the straw, ensuring it touched the same points every time, and then proceeded to turn the engine over by hand, making marks as I went. By measuring the distance between the initial and final marks on the straw, I was able to determine the stroke of the engine.
After performing the test, I found that the stroke measured to be that of a 390 engine, confirming my suspicion. This surprising discovery led me to decide to keep the truck intact, as it ran well and had a powerful performance on the road. It turned out to be a great deal for $1,000, and I was pleased with the outcome.
Furthermore, I conducted the nickel test to check the engine’s smoothness and stability. I balanced a nickel on the carburetor’s float bowl, and the engine ran smoothly, demonstrating a nice, low idle and a smooth balance, further reinforcing my satisfaction with the purchase.
In conclusion, the straw test proved to be an effective method for determining the engine stroke, and it allowed me to make an unexpected discovery about the truck’s engine. The 1976 F250 turned out to be a great find, and I’m looking forward to working on it in the future.
What type of engine does the 1976 F250 have?
The engine is believed to be an EFI engine, and there is uncertainty whether it is a 360 or a 390. The owner wants to verify if it is indeed a 390.
How can you determine if the engine is a 360 or a 390?
You can determine the engine type by measuring the stroke using a straw and a permanent marker. A 360 has a 3.5-inch stroke, while a 390 has about a 3.25-inch stroke. By making precise marks on the straw while measuring the stroke, you can differentiate between the two engine types.
What were the results of the stroke measurement?
The straw measurement indicated that the engine is a 390, as it had a stroke measurement well past 3/4, confirming that it is indeed a 390.
What is the condition of the engine in the 1976 F250?
The engine runs well and has good power. Additionally, the pushrods are being checked to address any potential issues, such as bent pushrods, commonly associated with EFI engines. The owner has overall had a positive experience with the engine.