All Carter/Edel carbs are
great carbs. See below. Carter 625 AFB v 600 Hol. Carter made more tq & hp.....& used less fuel doing it.
Spread bore. The term appeared when the QJ appeared in the mid 60s. To accommodate the huge 2.25" sec t/blades, the c/line of the t/bores had to be 'spread'. Hence the name.
I doubt whether an AFB, AVS or TQ will seal to that manifold without a spacer. There is very little flange metal left on the sides & rear of that intake to seal without an air leak. May fit without a spacer/adapter, would need careful checking.
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