According to the table for exhaust systems at 5000 rpm a '76 made 109 HP and a 77 made 118 HP. The exhaust manifold was the same. Where did the extra 9 HP come from?
What is interesting is that the 76 had cam LC's of 114. 114 and the 77 had 102, 102. My guess is the difference is cam timing and not exhaust system.
85 GTV6 3L
76 Suzuki GT500
2011 Jaguar XKR
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