cars with non original engines, What affect on value does it have? Options

[dw914six]

If I am looking to add another 4 cylinder 914 to my garage, some of the best examples do not have numbers matching engines. At some point the PO of these cars has wanted more power and upgraded to a more advanced engine.

My question is what happens to the price when the engine number is not original to the car? Is there a rule of thumb?

(I know it's market driven and anyone can offer any crazy amounts (IMG:style_emoticons/default/wacko.gif) for a car they just have to have)

I'm just looking for the norm if there is one. Is it something like current market value less 25% for non originality factors?

Any thoughts? (IMG:style_emoticons/default/confused24.gif)

[rick 918-S]

IMO rust is the issue. As long as you stay air cooled, any documented solid chassis car with an upgraded 2.0, nice interior, nice paint and no issues with the brakes or handling will command as much as a rust repaired numbers matching car in the same condition.

These cars are still driven hard everyday. Parts are still fairly abundant and parts cars are still around for what you can't generally find in the new market. With all that making this a common car on the desirability scale the prices are still climbing.

BTW: how many other 40+ year old cars from other manufactures are being driven regularly across country and thrashed all weekend and getting their owners home with very little drama? (IMG:style_emoticons/default/idea.gif) (IMG:style_emoticons/default/shades.gif)