I have never heard or used anything from Precision engine, but do have a 479ci/383 based 0.040" over 4.290" bore & a 4.15" stroke crank... In my current car... I've built several of them now too, among many other wedges & hemi's, for the racetrack & street, Blown/Injected & Naturally aspirated, single & multiple carb combos... a 470ci 3.95" stroke, offset ground 440 crankshaft b-main specs & 2" rod journals {use BBC rods end sizes}, a 431ci 383 0.030" over 4.280" bore, 440 crank 3.75" std. stroke, b-spec ground the mains & counter weight radius down to 7.120" {7.20" max dia.}, also had a 4.25" stroke combo in a 383 block {the blocks are easy to find & cheap usually}, I also always used a block/pan rail girdle on any stroker combo, for added strength, in a Low deck B or tall deck RB engine... But honestly IMHFO the Low deck B series 400ci is a better block, slightly better/stronger main web strength {smaller main bore than the RB blocks & bigger 4.34" std cylinder bore}, even than the 440 RB tall deck block {you could run a longer rod thou, for better rod to stroke ratios, in a 413-426-440 RB block} & 400ci B-Low deck has a much bigger bore 4.25"/383 std vs 4.34"/400 std bore to start with, to gain a few more cubes 0.90" bigger... I stayed with the 383 block in my current car/build just because I wanted to maintain the #'s matching parts, but it's not a necessity really, it was more of a personal choice, the 400 internal parts are cheaper too, more piston choices available, than for 383 you more than likely will need custom pistons driving the cost up some... Nothing wrong with a stroked 383 B-series low deck Wedge, I've gone 8.58 @156mph with a one on N20, went 9.77 @ 135mph N/A, full roller alum. head race motor/727tf, they can/will make plenty of power... just for the sake of saying it, for those that won't know,The smaller 4.25" bore could limit intake valve size {to 2.14" with out nothing the edge of the bore} & cylinder head flows, the heads ultimately flow better, especially when ported, flowing into a larger bore, you can fit a larger valve, into a lager bore too, with out the intake valve being shrouded slightly @ higher lifts.... good luck
