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The official club for enthusiasts of the

1970 & 1971 Oldsmobile Cutlass Supreme SX


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Bob Peters
SX455 Club President
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NEW Restoration Questions

Author Last Post
Being that you're asking the question you probably anticipate the answer. Yes, a non-numbers matching motor will impact the value of your car and the vlaue of cars in most collector circles. In my opinion, there are more factors to consider though. A factoring appearing replacement in an original appearing and otherwise correct car might have minimal impact particuarly if the motor is correct model year. Value also depends on the buyer and how much they value a numbers matching drivetrain. It's also still a GM big block, A-body muscle car which in itself is a good thing for value. It's unlikely at this point you can change the fact its a NOM drivetrain so the decisiion at this point is yours to make - keep it all original appearing and as correct as possible and take a perhaps small hit on the non-original motor or forget about it and just enjoy it. Depends on what your particular plans for the cars are. But, it's still an SX and still a fairly rare car. BTW, my first SX was a NOM car also. I went the first route and kept it all as stock looking.
My sx has a 73 455 in it. The engine needs rebuilding but drives. I want to rebuild the 73 engine even though I know it is not numbers matching. Will this drastically decrease the value of the vehicle? I am building my sx for fun, so I am not too worried about not having a nummbers matching car. Any thoughts?
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