Nobody seems to have a map for the 55 trim compressor except Garrett and they don't seem to want to share. This is probabally because its very good and they don't want others to reverse engineer it.

I would think that the 50 trim compressor wheel would build boost at a lower rpm than the 55 trim compressor wheel, however where boost starts building between the 45 trim and 50 trim wheels is negligible. If you have both turbos and a boost gauge try it and see.

I'll buy the 55 trim compressor wheel, compressor housing, and back plate if you don't want those either.

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green 85 300SD 200K miles "Das Schlepper Frog" With a OM603 TBO360 turbo ( To be intercooled someday )( Kalifornistani emissons )
white 79 300SD 200K'ish miles "Farfegnugen" (RIP - cracked crank)
desert storm primer 63 T-bird "The Undead" (long term hibernation)

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