Holley SD is not a good choice for that combo. Holley SD likes more timing than a dual plane even on a combo it's suited for, which is one with torq to spare.

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I do understand that all carbs may need tuning to get optimal performance but I would think the Thunder Series AVS would run pretty good right out of the box.



You can never assume that. I have a wideband o2 on my car, and trust me, baselined or out of the box tuning can be miles off. For example baselined to stock specifications I was getting a 17:1 a/f at a hot idle as well as cruise and a bad bog at WOT with my thermoquad. Not the same as an eddy thunder but mine's a 440 pre-smog era thermoquad an on the new combo it was crazy far off from ideal.

I've got a low-cr smog 440 stock bottom end w/ new piston rings, lunati voodoo 60303(226/234@050, 494/512 lift, 110lsa) cam, 440source heads, headers and a stock spreadbore intake w/ thermoquad. I was going to do a full rebuild but didn't have the money and decided to throw something together to have fun with instead of sitting on these parts until the end of time. It fries tires great off the line, the back end goes all over the place. Great street manners and I still drive the car to work and will do so until the snow flies.

FWIW my cylinder compression ##'s were a bit better than yours, even with the bigger cam.