Why did Porsche make 2.2 liter engine in 1970 vs. a larger displacement?

[1QuickS]

The 2.0 911 engines fit into class limits for engine size at the time. When the 2.2 came out, were there similar class restrictions for engine displacement that Porsche was looking at? Otherwise, a larger engine like a 2.5 would have been pretty sweet in 1970.

[70SATMan]

That’s what I want in my 70. 2.5 SS.

[Biancaneve]

Because then they would not have reason to introduce a 2.4 thus rendering "obsolete" the 2.2 ... marketing, I guess

[davep]

The 2.2 really needed just a bore increase, and they added some head changes to the mix. Then the 2.4 needed a longer stoke crank, and maybe the testing of this crank needed the two extra years development. Besides, we become horsepower junkies, so we need an upgrade path every two years.

[RSTarga]

They were also getting their asses kicked by the Ford Capri in Europe

[1QuickS]

They were also getting their asses kicked by the Ford Capri in Europe

This is more what I was thinking. The Capri was a V6, right? What displacement?

[RSTarga]

I think they were 2.8 v6, then BMW brought out the 3.0 CSL and so on so on.
I can't remember the precise homologation rules but it was a main reason of the Carrera street at 2.7 race 2.8 then 3.0
Each one upping the ante.
Even here in SCCA the Alfas were winning so Porsche came out with thinner rear seat cushions to compete as a sedan, racers always looking for a loophole.