I've been somewhat skeptical of some of Buicks specifications for the str's for a few years now......Cooling my heels for a while now in California, I've had some time to think about things. I was looking at the given torque & hp specs for all the str'8s and the given rpm at which it occures and it struck me; this is low rpm for max torque values, WAY too low. Max torque production is a function of stroke. That is, short stroke, higher rpm, long stroke, lower rpm. It could be that 2100 rpm (or so) prehaps may be peak torque but it is not potiential torque peak. Since this is a function of stroke, it should be plotable on a graph, to give at least a basic visual idea of where peak torque should occure, rpm wise. I went over to the library and dug up as much info as I could and ploted a graph. T he 320 comes in about 4200 and the 248 & 263 about 4400, + or - a 100 or so rpm. Hmmmm, this rather changes things. How Buick actually measured their engines, I have no clue, sliderule guesstimate? Engine efficency follows the torque curve. Peak torque at about 2100 rpm probably means that the head flow is starting to choke at this point and its downhill from there. With a potiential torque max at 42-4400 rpm, potiential max hp is actually about 5500, with a average cam. The head is killing us. We are not thinking about the actual weight of the parts going 'round in there at this point. Since the 320 has bigger ports, it has the best chanch of getting in to "the 5's" I don't think there is enough meat in the ports for the small head to flow in this neighborhood. Sure would be intresting to send a head or two over to Air Flow Research and tell 'em "Take no prisoners". alleycat
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