They would do 60% but said it would be too unpredictable on wet ground. And it would wear tires fast. They HIGHLY discuraged 60% for the street. If I can ever get my project going again I could tell you how fun the GT diff is.
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1970 T1 W/MassIVe 2913cc RAT/?EFI? w/direct fire (very soon) and 915 trans
1962 SC 1776cc SP 944NA brakes, 993 wheels
VKG