I spent some time searching some Hemi topics on here and thought I would share a pair of 354 Hemi heads I recently built for a project I'm working on. I call them "Heinz 57" Hemi heads because they use a SBC intake valve, Pontiac exhaust valve, and a LS Beehive spring - a little of this.....a little of that. The sole goal was to lighten up the valvetrain while using shelf parts for a street performance oriented head. I took some stock 354 heads, installed some bronze Hot Heads 11/32 guides (thick liners could be used with stock guides), performed a good quality valve job (proper and matching seat depth is critical), and did a light surfacing to the heads to clean up. There was some extra machining to do on the guide OD to make a LS spring seat work properly using a spring pocket cutter and also machined for PC seals. I don't run seals on the exhaust side on Hemis, not enough oil there. The LS springs in general usually take a 1.800 installed height so matching that with a 5.160 length valve you end up with a nice setup that can still work with stock rocker arms. I used a PAC Beehive spring that I could get a little more seat pressure on for a final 1.770 installed height in this particular case. The SBC valves range in size from a 1.94-2.125 if desired at this length, just need porting done to compliment the valve size. The exhaust is a 1.770 and fits the exhaust throat size nicely when using a radius seat cutter. The exhaust ports are plenty big and flow around 190-200 cfm @ .500 lift with mild port cleanup which is sufficient for a mild street motor. Be sure to smooth the ledge on the short side radius. I did do a mild port job on the intake side and they flow 280cfm @ .500 lift. Nothing trick here like raising the roof just opening up the bowls to the last angle of the valve job (5 angle in this case) and widening at the pushrod walls a bit without breaking through. Just proper and sensible porting techniques. If you happen to break through no big deal just get a .014 wall bronze tube to sleeve it back up and seal with red loctite before installing. It may require you to use a reamer in the hole first for sizing, you need a slip fit. A 5.160 length is the longest you can possibly go with stock rockers so you really have to understand your boundaries here! The sweep pattern isn't optimal compared to aftermarket roller rockers but it does work without issue. I spent a long time mocking it up and checking geometry using non adjustable rockers. I think this is a really neat setup to do for a street motor and the springs can handle .600+ lift pretty easy if desired. If you need more spring pressure for a more aggressive hydraulic roller or solid flat tappet cam then you could look at the LS Dual Spring kits.These heads are going on a 10:1 354 Hemi that we are using to get some licensing passes done at Bonneville (if it will ever dry up). I did a custom grind hydraulic flat tappet cam for it that was a 236° @ .050 with .522 lift on a 110° lobe separation Thanks Chase at Crane! Anyhow just wanted to share a simple setup that I think many on here could use for their Hot Rod Hemi.