[rb25stu]

rb. race bred
20 2000 cc
25 2500 cc
26 2600 cc
d double over head cam
e sounds daft but it is (injection)
t turbo
tt twin turbo

so an rb 20 det is a r32 gtst
rb25det is 32 33 34gts/st /gtt
rb26 dett are the gtr,s