Borg Warner T10 vs Toploader

[Dan Case]

Originally Posted by CompClassics

T10 transmissions have been installed in nearly all the major auto manufactures most powerful big block powered manually shifted drag cars, 409s GM, 421 Pontiac, 406-427 Ford & Mercury. Yes, evolution within each manufacturer may have lead to each manufacturer developing their own transmissions or the development of improved transmissions but the simple fact remains, the T10 transmissions had been backing some of the most brutal engines built in some of the biggest cars built at the time.

Very true but tire technology back then was very primitive as compared to now. The very best racing tires 1960-70 were not as good as the tires a typical entry level economy sedan gets now. My 2015 F150 truck has “better” tires than my 1970 Boss 302 and 429 Mustangs had. Relatively skinny relatively hard rubber compound tires of the 1960s didn’t “hook up” all that well and 1960s cars didn’t have computer controlled engine, traction, and handling management.
The people that I knew or knew of that drag raced Cobras before they got too valuable didn’t want to get traction too soon. If they hooked up too soon something was going to break including drive shafts, clutches, transmissions, half shafts, and rear hubs. The person I was most impressed with ran Cobras and 427 Cobras. He barely spun a tire as he left the line. He was very quick still but was easy on the original drive trains.

Original street Cobras weren’t engineered for super high torque engines and high traction wide tires. SAI increased the load capacity of all most everything that rotated in their race cars. Ted Halibrand and other suppliers provided higher strength and higher fatigue resistant parts to SAI that just anybody could not go buy at their dealer’s parts department. Even with upgraded parts T-10s were not as tough as some users. If you have read a lot of SAI racing history you will come across tales of some drivers being very rough on transmissions while others didn’t have any problems