Brad H sent me the 4150 to try Andy and it was a mess and I put my normal tune in it and it was not happy till after 4000r's and up.....Plus 4150's don't belong on BB like mine and others making decent power in my world and I put my Dommy back on and all good. I think Brad dyno'ed it as well iirs and it had issues....
My recollection of that carb is it was a Holley XP950 that had annular boosters installed by Mark W(but I may not be remembering that correctly).
Whatever that carb actually was.......It did indeed still have issues on the dyno(very rich at part throttle....... very lean at WOT).
He had brought several carbs to try, that being one of them.
All but one showed that same tendency. Very rich at part throttle, very lean at WOT....... even with quite large jets(which just made the part throttle issue worse).
I had brought my HP950 dyno mule along(as a “just in case”) and after we were done with his carbs(and it was clear they were going to take some fairly substantial reworking to get “right”, we bolted my carb on........ more or less to verify that the issues we were seeing were in fact related to the carbs themselves.
My dyno carb worked just as it always did. Fine at part throttle, and required no jet changes for normal A/F ratios at WOT.
There was nothing with the engine combo that was presenting some unusual demand that the carbs were having trouble dealing with....... the basic carb calibrations just were way off..... simple as that.
