A question and maybe an idea about engineering times

Straight to the point -
imagine, that you have a production of 86/86 V6s or I6s and they are produced for over 20 years, obviously the production and engineering will be nailed to perfection, but what if you want to make an 86/86 V12?
will the experience from building engines for long periods of time help reduce the times for engines that are similar in design?



thank you, missed it