Yep, dropped a valve, shattered a piston so it is rebuild time. I have been contemplating this for at least 6 months but thought I had more time.

Known and Unknown:
I want more HP, I've been told 20 over was the most I could bore these engines but by looking at it I could go 40 or 60 over easy. Then more research is finding parts, pistons are tough to find, cams easy. Then I was told by one tech to upgrade to high volume intake I would need different heads... told by another that on the 3 valve.

Questions:
Has anyone on this forum done upgrades to these modular 3 valve engines and how did it work out for you.
Do I just need to grab a long block and be happy my truck runs.

 

This is what Ive found so far.

From Summit
450 lift stock
Cams - 2 available
cca-127050 stock driveline - $744.97
cca-127200 more gear & stall converter - $745
cca 5449 - phaser limiter kit..
need 3 valve heads Summit does not carry them.

Pistons, dish or flattops
no mushroom pistons Ive found yet.

Factory piston bore - 3.552
Im wanting to bore 40-60 over but they told me 20 was most.

 

Mahle possibly has pistons for this engine. Saying that would still need heads, valves, springs etc.

Mahle - 888-255-1942
Propak series

 

If this is a street engine, you need to make sure the cam won't cause the cats to melt. I suppose the term "emissions legal" is the key description.

Boring 0.060" over doesn't really do that much for hp. This engine already has a 4" stroke I believe and I suspect dished stock pistons. Calculate the compression ratio with any different design pistons. I would think aftermarket heads would be needed for major hp increase.

You may get the boost in performance you are looking for by going to a lower rear gear.

 

Have you checked out these guys? http://www.modmaxracing.com/default.asp

 

Bore adds very little HP or TQ. As an example, consider that if you're making 1 to 1 HP to cubic inch, boring it 30 over would add what? 5 maybe 6 cubic inches? so 60 over would add 10 to 12 cubic inches (I'm guestimating here, so don't nickle and dime me on the exact cubes). So a 60 over bore would add maybe 12hp. That's best case too since making 1 to 1 HP/CI is something these 5.4's do not currently do.
Sorry I can't be more help, as learning the power limiters of the Ford 5.4 is something I've spent 0 time on... but as with all engines, higher compression makes more power but you may need to run higher octane fuel to compensate, and the most important lesson is more air in + more air out = more power. Usually that means bigger intake + bigger heads + bigger exhaust = solid gains. Bigger cam is optional depending on your situation. Or you can take the ultimate easy cheat and put a supercharger on it. Root style chargers make good power from low RPMs.