It starts with a philosophy of use (POU). What type of driver are you? How do you envision driving the car? Do you want to row fast and spin the motor to 6-7K? Do you want a street motor that you row from 2nd to 4th all day in the city? Or something in between? I have both a 1600 and a 2276. Not an apples to apples comparison because the 1600 is in a 912 and the 2276 is in the Vintage Speedster. I prefer to drive a slow car fast and the 912 fits that POU perfectly - it is a momentum car and time seems to stand still when ever I drive it. And that is a good thing.
The Vintage with the 2276 however, is quite the opposite. The 2276 is a lazy mans car that has momentum in any gear. Though it falls on it's face after 5K, I have a large area under the curve and it pulls through the gears pretty QUICK. The ride can be over just like that. The 2276 is surprisingly fast says my buddy with the Tesla 3. But sometimes I wish I had a 1600 in it. Good luck with the project!