Pontiac 421 Super Duty Tripower (Hot Rodded)
by Alldegree

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When making this engine, I was inspired by a 1963 Pontiac Catalina that was used by flight engineers at NASA to tow M2-F1 glide vehicles at high speed. 1963 was still the early days for NASA, and they didn't allocate enough money in the glide body project to allow the use of tow planes, so NASA engineers bought a 1963 Pontiac Catalina convertible with a 421 Super Duty and modified it to run at high speeds on a dry lakebed. Although the glide body design was eventually shelved, the data it produced would later be instrumental in designing the space shuttle.

This particular motor has as many correct dimensions as I could find online. I also used AI for some of the harder to find specs. Some measurements are pure estimation after much trial and error. Is it precisely correct? Probably not, but It does make over 600 HP and 600 lbft of torque, so I like to think it's pretty close to the motor that was in the NASA car.

Feel free to make changes and improvements.

I also included:

• A vehicle with the same weight as the 63 Catalina, I guessed on the drag coefficient
• A 4spd transmission with ratios matching one of the transmissions offered by Pontiac at the time (there were many)

Issues:

• The engine will often flood out and die after bouncing off the rev limiter. I tried many different changes to fix this and will reupload if I find one.
• When starting, you have to have the throttle open a little bit in order to get a good enough AFR to start. As above, I tried several things to get the motor to turn over normally, but so far I haven't found a solution. Once it gets going, it should settle at about 850-950rpm.

It's not a gigantic 426 Hemi or a fire breathing LS, but I hope you enjoy this unique interpretation of muscle car history!

Edit 4/1/24: Added some notes to the script, adjusted dimensions of the vehicle to match those of the 63 Catalina. Cd is still an estimate though.