So I have changed plans several times on my truck motor and am currently building a new one for it just because I want some more power.

I am mentioning this here because there is a ton of bad and weird and just plain wrong info out there for this swap so figured I would clear the air on how it is going on mine.

For a little preface, I milled this block .020 to bump compression and quench, I figure it bumped compresion about 1/2 point.

Today I assembled the 5.7 short block with the 6.4 MDS cam and a dissasembled cam phaser and tested valve clearance both in full advance and full retard as well as 1/2 way between, on both intake and exhaust and found over .050 PTV clearance at all times, (I collapsed a lifter, shimmed the valves just barely closed then added .050 more shim and bolted the rocker shaft back down, rotated through many revolutions with no sighn of touching) may have been more but I stopped with that because that is all I care about, I am not spending $1000 on a cam and cam phaser limiter. So on a stock block there should be even more so I see no reason this could not be done in the truck, in a day and without removing the heads. The 5.7 spring might even work(I would at least buy new ones, they are under $60 from the dealer) or better yet just buy the 6.4 springs, they have a tiny bit higher spring pressure.

This might not be an awesome cam but I don't see how it can not be good especially when considering the cam cost me $68 and I needed a new cam anyhow. A lot of guys are saying you have to install the comp cams phazer limiter, that is grade A bologna.

Hopefully someday soon I will have an update how this thing runs. Probably gonna at least tough up the ports and VJ since I got the heads off anyhow. Hope this helps clear the air about this swap.