A 750 is a bit small on a 493, but there isn’t a magic 50hp from a carb swap either, especially if the current carb is one of the chokeless HP style pieces.
If the heads haven’t rec’d any porting, that’s where I’d go if I was looking for a more meaningful power gain.
Of course, that’s a way more involved proposition too.
Without some tweaking, the 75cc Ede heads have more valve shrouding and less low/mid-lift flow than the 84cc version.
If the current carb is a HP750 style, and you went to something like a QFT 950(1.450 venturi), both tuned for max power…… you might find 10-15hp.
The fact that the HP number is noticeably less than the TQ number is an indicator that the engine is air flow limited(can’t carry the TQ high enough in the curve to make a big HP number)…….. primarily heads and intake imo, and to some degree the carb too.
Of course it’s a snowball affect thing…….
Once the heads were ported, and a single plane intake installed…….. then the 1-7/8” headers would start to become a cork.
But…….. for what the basic combo is……. The numbers look about right.
Edit: after looking thru your invoice it appears there was 23.5hrs of porting on the heads?
If that’s the case, then I’d say the numbers are low(compared to what I’d expect to see here).
But, as I always say…….. it’s never wise to try and compare numbers from different dynos as “apples to apples”
Edit 2- I dug thru some sheets I had here……..
493 with prepped/blended std port Indy EZ heads, SD intake, similarly sized SR cam, 2-2 1/8 dyno headers, original Holley HP950.
HP and TQ within a few numbers of your sheet, with peaks occurring at about the same RPM.
