Hi people. I'm in the process of building a 451 & I'm stuck @ rod length, I've heard very good pros for both long & short rods,
My 70 dart will be running an automatic 26-2800 stall with 3.91 gears in 8.75 and mostly street driving..the cam is isky z-35 solid flat tappet it's 254°@.050, mild ported stealth heads & low rise single plane edelbrock torker. With this info & being a big block in a light dart would my bottom end torque be effective enough to just drive with street manners. Short rods better at low & mid range. Long rods mid & hi rpm. But will there be that big of a difference ? Any real world experience with both types out there ?
that combo will be just fine on the street. in my experience, even big blocks with the higher RPM setups make more than enough torque down low to move down the blvd quite nicely. combined with a nice intermediate stall and 3.91s, you should be golden.
honestly, until you're working hard to shave hundredths or thousands off of an ET playing with rod lengths (short vs long), you're unlikely to really 'feel' a ton of difference in a car where you're concerned with 'manners'.
I went with long rods in my 4.15 stroke 500, and it makes for a very short piston, which results in piston slap. If I was doing it over I would have gone with the shorter rod. The upside is the piston is very light and it revs like a small block. Yours is only 3.75 stroke, so it may not be as much of an issue.