DynamiteSpeedGarage
Active Member
I have just acquired a '51 331 hemi and I have already a 904 auto trans in stock. Would the 331 bolt up to the 904 trans? Is there an adapter plate for this? Or do I need to use a different trans?
First off, is it an extended block or not? Makes a huge difference.
Extended:
View attachment 1716276464
Not:
View attachment 1716276465
If it's an extended block, try WilCap (https://wilcap.com/index.htmlor) or HotHeads (https://hothemiheads.com/transmission_adapters/index.html) for adapter kits. The adapters are for 727s, but they work with 10" convertors, so you may get them to work with the 904.
If it's an extended block, good luck. Sorry.