My Transformation 5.7 Gen 3 in 74 Dart Sport

Ronald C. The 6.4 works great in the 5.7, the best cam to use is the one for the 6 spd Manual trans(non MDS cam) part# 05037379BC. The cam smooths out the power curve of the 5.7 Eagle and really pulls hard from 3000 to past 6000 RPM's. If your engine came out of a manual 6 spd car all you have to do is change valve springs. The 5.7 springs has a 1.99 installed height and go into coil bind at around .550 lift. The 6.4 springs are 2.051 installed height, so even the 6.4 will be close to coil bind on the Eagle head. The Mopar Performance P5160074 spring kit is what you need(good for .625 lift) or the PSI 1511 springs(same .625 lift) with Comp Cams 761-16 retainers and Manely 42324-16 spring cup locators(.205 thick)plus 8 .020 shims for intake and 8 .030 for exhaust( remove the factory .040 shims) to get close to there 1.800 height. Know if you have a 5.7 out of and auto trans car you have to pull the heads and change the lifters too and shut off the MDS. Or use the 6.4 auto cam( just change springs again) which may or may not work as good as the manual cam( read of some guys losing power with the auto cam, could have been the tuner though). This set up works even better with the 6.4 SRV intake manifold set to go into short runner mode at 4800 rpm's with a MSD 8969 window switch and long tube headers. All of these mods will need a good tuner to work there best. Will run on stock tune but not at its optimal and may through CEL codes