I'm not suprised the 2d held it's own and I'll bet the torque in the 3000-3500 range was stronger compared to the 337. at 4100 pounds I'd
that torque curve and take the one that averages best from the bottom of your high gear cruise RPM to your shift recovery (4 speed) or flash RPM... as close as they are up top whichever one averages higher is probably going to ET a heavy car the best.
What I was saying about the 180 degree plenums and more potential is that to make 710 on the dyno the "good" plenum may be making (1/2 of) 730 and the "bad" plenum only (1/2 of) 690 so you average 710 because basically 4 of the holes are not getting fed as well and not pulling their potential weight up top.....people would kill for another 20-30cfm out of their heads (~4 cfm is potentially 1 hp per cylinder) and ideally for max power your manifold should outflow your intake port by several percent.
as I remember the best to worst is about 35 cfm so the split might be even more, no way to tell unless you read thermocouples off each cylinder.
Also remember that a dual plane almost always wants a larger carb to compensate for the fact that it really only "sees" 1/2 the carb as oposed to a single where each runner has all 4 barrels available to it. That why my 2d is coming off, to see if an 1150 dommy can be bridgeported to fit and open up the plenum even more (which can have a similar volume effect as adding a spacer), it should be fun and stealthy.
If they're that close I might stick with the 2d....being I've got "only" 517 puny cubes
But now I know I suspect I might as well go all out on the 337 port job to see much of a difference on my combo.
What's really intriguing is that the 440-2 Big Single didn't really gain all that much showing that it really needed more Compression to show it's hand.....cubes alone weren't really enough. If we compare the 572 to Brian (Old School's) 13.5
:1 numbers with a similar cube motor it makes for an interesting comparison. I think my heads are on par but I got a lot less lift and and 55 less cubes and my cr (11.87:1 calculated) is right dead in the middle.
Great info!! Thansk to both of you for all the hard work and sharing the data!!
Needless to say some Coke bottle B bodies are packing some serious punch around here! huh??
