Car Value: Replacement (Warranty) Block vs Original Block vs NOM

[cwestra]

In general, using a numbers-matching engine as the baseline, what's the typical value reduction (%) when there is a warranty block (no numbers on block) in the vehicle.  Similarly, what would the typical %-age loss be (again, compared to numbers matching engine)  if the car had a "period correct" non matching motor in it?  Assume we're talking about a Mopar muscle car (1968-1971 period).

And is there a considerable loss in value if the trans is also not matching?

[dfrazz]

If #'s matching is 100% of value, I would say a warranty block (which is very difficult to prove) is a 15-20% reduction, a period correct engine is not much more different than any other engine (for a '70 Cuda a '69 340 vs. a '73 340) and reduces the price by 50%.   

For example, if you have a '71 #'s match 426 HEMI Cuda selling for $200,000 then I would expect a non-#'s match 426 Hemi for around $100k.

[anlauto]

50% is a little steep in my opinion....Using that math...The V code Challenger I recently sold for $85K would be worth $170K with the original motor.

As for your other question. I think to have the correct "dated" motor is essential if the original one is gone, but I don't think a "warranty block" or "blank VIN" block adds much value unless you plan to stamp your VIN into it

[cudabob496]

I think, as time goes buy, original parts become less and less a factor in value.
Quality built cars with quality new parts are selling for just as much, if not more.
Why, because the car is made better, with technology that is not 50 years old.