85's would have slightly less pep due to the 2.88 gears in the rear end. They also have a nasty ARV that will drop your boost. If its a Cali car performance will be crippled by the Trap Ox/Ox Cat .

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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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