RTS Aluminium Bellhousing for GM TH400 RTs or Reid Aftermarket Case. Using the latest casting technologies, RTS has designed these cast aluminium bellhousings allowing many popular engine/transmission combinations to be easily mated together. They have gone through SFI’s explosion-proof testing procedures and have come out the other side with a SFI 30.1 rating! Manufactured from one-piece A356-T6 cast aluminium, they are roughly 5 times stronger than standard replacement bellhousings and can withstand the harshest tyre shake, while still being able to fit under most floorpans. SFI 30.1 Certified Works with Aftermarket Cases, RTS, Reid A356-T6 cast aluminium Precision machined 5x stronger than OEM Works with most 11” and smaller torque converters Bolt on Aftermarket Cases