I had a compton converter 2800 lock up in my A518, I now have a 4000 lock up that was built for my combo,it works awesome, PATC brand. 512 lowdeck

1968 Charger COLD A/C Hilborn EFI
512ci 9.7 compression, Stealth heads, 4.10 gear A518 ODtrans 4100lb,10.93 full street car trim
2020 T/A 392 Stock 11.79 @ 114.5