I recently picked up a Bullnose with a carbureted 302 and C4 Transmission. I rebuilt the rear axle and know that its running 3.55's, with 28" tires. I'm running at 4,000 RPM at 70 MPH which the math doesn't add up when running the calculators... The transmission sounds and feels like it's shifting fine, any ideas why it's spinning so high? I have no idea what torque converter is installed.

 

What stall is the torque converter?

Here is how to determine that: With the trans in D and your left foot HARD on the brake pedal, use your right foot to plant the go pedal on the floor. What RPM did the engine reach? That is the converter stall speed.

NOTE: DO **NOT** HOLD THE GO PEDAL TO THE FLOOR FOR MORE THAN FIVE (5) SECONDS!!!!! MORE THAN THAT WILL DESTROY THE CONVERTER. Idle or fast idle the trans in park after this for at least 30 seconds to cool the converter.

 

Looks like a 2000 rpm stall.

 

That's in the normal range for stall. Are you certain the transmission is shifting twice?