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yer absolutely right,i thought about that after I posted.
heres another mahle piston with a 1.350 ch that can be used for my application with a 6.535 rod and the 4.150 crank. would need the cut .020 from the deck for 0 deck. piston weights about 500g.


The 4.15 stroke with BB chevy rods is shorter, less stroke= less torque The 4.25 or 4.300 stroke is way better than the 4.15 stroke Especially if your going to put a decent set of heads on it to start with I've built 4.25 stroke motor with the stock Mopar rod journal sizes, lots of block grinding needed to make them fit I've built the same combination with the 4.250 stroke with BB Chevy rod sizes and forged H beam rods and those needed a lot less grinding, the rod bearing speed is a lot less due to the smaller diameter rod journals at the same RPM, the rotating assembly is lighter, especially if you use a long rod, and a lot less grinding is needed on the blocks, as already pointed out The original 4.150 stroke was a easy way for Mopar to make a cheaply available forged steel stroker cranks for the aftermarket race car sales division of Mopar, it worked good back in the day The 4.250 stroke 2.200 rod journal size cranks are better




Cab your talking like "we will say a 383 to a 440"
the 4.15 will rev higher and most likely will have
the torque in a higher range than a 440... so if you
want the torque at a lower rpm then yes the longer
stroke is better but if you want a rev engine then
you go with a shorter stroke.. so was the 383 a bad
engine... nope but the stock version wasnt set up
as a rev engine so it lacked in the torque... every
engine has a place and where it makes the torque...
but I think we will agree that RPM is power... if
its set up for the rpm