Need more information:
1. What is your intended driving style and regular use of the car?
2. Was the Demon originally a 318 automatic, or 3spd manual on the floor?
3. Did the Demon originally come with a 340 automatic, that the 340 blew up so they put in the roller 318?
4. What is your rear gear ratio and does it have 14" or 15" wheels?
If the Demon came original with a 340, then it likely has the 8 3/4 rear end with possibly 3.23 or 3.55 gear ratio?
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