R=supercharged. TT=twin turbo. A12RTT. 'Nough said.
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A12TT
go_the_datto ran this in his coupe until he got a CA18DET.
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Twin-charged
Prototype: the supercharger could switch off above 2500 RPM and the twin turbos could take over from there.
1200rallycar bought the TT setup off GTD, and turned it into the famous A15ETT.
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