5.2/5.9 H.P build guesstimate

If you look at the dyno curves provided, the 350 hp 5.9l makes about 330 hp @ 4700 rpms, 400 hp 5.2l makes about 340 hp @ 4700 rpms, 365 hp 5.9l makes 355 hp @ 4700 rpms and the 400 hp 5.9l makes about 380 hp @ 4700 rpms, if you notice the 5.2l ain't doing so bad plus you should be running deeper gears with a 318 so it would be revving higher in rpms and in hp at 65 mph.

Plus in the 4900-5000 rpms the 318 is making the same power as both the 350 & 365 hp 5.9l and still makes usable power to 6200-6500 rpms 400-393 hp if one chooses to rev up there if not it's still makes similar power at 5000 rpms as the lower hp 5.9's. Not trying to get you to build the 5.2l it's up to you, the really only reasons to run the 5.2l you already have it and more importantly if you want higher rpm power and are fine with the possible side effects if not build a 5.9l but no reason not to build a 400 hp 5.9l if you look, its basically make better power every where except above 6000 rpms.

Some seems to think more power only happens at the top end of the power curve forgetting it can add through out especially mid curve 3000-4500 rpms where like someone pointed out you'll spend a lot of your time at full throttle.


Mopar Performance 360 cid 380 hp rated