Does "numbers matching" matter for a '74 911s?
 

Does matching numbers matter on a middie? I'm looking at a unmodified run of the mill '74 coupe (not a Carrera) that drives but is well used and needs a full restoration. The car has a 2.7 in it from a different year car. The seller has its original 2.7 available but it needs a rebuild.

I know that it matters in the 356 world but does putting the "original engine" back in the car add significant value to this car? Maybe I should ask, would any of you guys pay a significant premium for a numbers matching '74 911s vs one with the wrong year 2.7 engine all other things being equal?

In the current market it absolutely matters. Don't break up that car.

Not important today, but who knows about 10 years from now?

On older cars, it's often enough to have the original engine available, even if it's in a box on the shelf.

Excluding special performance models, speedsters, etc., a 74 911S may well end up being the most coveted impact bumper 911.

None of the standard impact bumper cars are going to turn a near-term profit from restoration, but a 74 S that doesn't need a ton of rust repair has as good a shot as any at returning lots of fun and the prospect of appreciation to boot.

I think it matters most if you intend to keep the car very close to stock (obviously, a timeserted case, Carrera tensioners, turbo valve covers, etc. are considered "acceptable" modifications). In that case, I think matching numbers matter a lot, especially for a '74, because so many of the mid-years have rusted away or have been highly modified because they were perceived as "undesireable." Because of that, there are relatively few good examples of unmolested, numbers-matching mid-year 911s, especially the '74s with the chrome brightwork, narrow hips and missing passenger-side mirror, and extra especially the 1974 911s models.

I own a pristine, completely rust-free 1974 911s in a unique color with numbers matching engine and transaxle. The engine is a little tired and the transaxle grinds and whines, but there's no way I would ever replace them, so I'm saving up for a proper overhaul rather than a drop-in solution. When I do the engine I'd love to ditch the CIS for electronic fuel injection "while I'm in there," but while I know it would pep up the car and make it more fun to drive I also realize it would detract from the car's value.

Mr Geologist, a solution many have adopted is to pull the tired matching engine is and drop in a happy 3.0 to get you down the road. Rebuild the original at leisure.