[goinbroke2]

Evan is right. Take a 1970 ford/chev/dodge at it's factory rating (.65...maybe.75) and build it to make 1.5 hp per cube and you got a runner.
Take a 2011 ford/chev/dodge that is factory rated at 1.3 for example, what do you have to do make 2.5-2.8 to be equal?

Weight is also an issue, a lot more **** can come out of a new car compared to old ones so that helps and the chassis are more rigid than ever.

I don't neccessarily agree with .65 factor on new engines as they are inherantly more efficient, BUT, you can't start a car out at 1.3 or 1.5 hp per cube or no one will build it.

Just some numbers of old random combo's;

77 Cad 350 180hp .51 hp per cube
76 chev 305 190hp .62
74 chrysler 400 290 hp .725
70 dodge 318 185hp .58
73 ford 351 240hp .68
72 ford 302 162hp .53

and some random new combo's;
2012 ford 302 325hp 1.07
2010 ford 330 435hp 1.32
2011 dodge 512 450hp .87
2010 dodge 345 305hp .88
2010 chev 376 400hp 1.06

My conclusion would be that the newer engines compared to older engines are starting out higher before any adjustments than the older stuff did. Slight mind you (.8 vs .6) but higher none the less.

This just leaves less "room" for improving. I don't want to build a 2bbl 302 at 300hp to start out with, but at 162? lots of room there. Do I want to start out with a new engine at 1.3hp per cube...to START with? Uh..no. Put it at .8 or so and then hit it as it's improved....like every other engine in the guide has done