Or do the economical thing, change belt when due.
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Between the custom pistons, connecting rods, and camshaft, plus engine rebuild, weāre taking about a $10,000 repair jobā¦
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ā¦ on a 12 year old car that might have a book value of $5k if it is in perfect condition.
Not that it matters but everyone that drives any amount will at some point encounter a very expensive repair. Sometime it can be foreseen and sometimes not. The only question going forward is whether or not to repair or just replace the car. I usually fix it and continue on my merry way. Not the first engine Iāve replaced but as Iāve said before, I donāt trust someone doing an overhaul, so itās either used engine, or crate re-man from the manufacturer. Nothing against all you folks that have done engines many times with good results, but too big a risk.
Technically Yes, you can send the cam(s) out to a cam manufacturer to be reground, or just order a custom grind from a cam manufacturerā¦
But you will kill the engine power, at this point just install a 5HP BS and be done with itā¦
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This would have additional negative effects compared to reducing the piston travel slightly. Each valve opening event would be shorter, and it would be more difficult to draw in air from the intake manifold, and it would be more difficult to expel the exhaust gases. With port fuel injection, you may not burn all the fuel.
In addition to killing performance, this could result in overheating, etc. It could also result in CEL trouble codes due to crankshaft/camshaft out-of-sync, excessive unburned fuel in the exhaust, etc.
The reason why custom pistons and connecting rods would be much better is that the cylinder head remains stock. The valve timing and ignition timing do not change, which means that the engine will run properly on the stock PCM.
That would lower the compression ratio, so it would also have a negative effect.
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Bro, you have the most āinterestingā comments . . . 
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Yes, the negative effect of less compression also means less air filling the cylinders and it will need less fuel, so the fuel injectors may have to changed (downsized) as well as the tune to control the lesser air and fuel requirementsā¦ It is the same outcome as raising the compression on a given engine, more compression = more airflow = need for more fuel = need to be tuned for all the above to work properly, but decreasing compression would be the reverse all of thatā¦
At least it is a legitimate comment this timeā¦ lol
BTW all you need is dished pistons to lower compression, same with raising it, I raised compression from the pistons, cut the block and heads down, rods had nothing to do with itā¦ Custom rod length and pistons together are for custom strokes from the crankshaftā¦
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But after lowering the compression you will gain back performance when you add the second turbocharger.
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Seems to me like lowering the compression would be worse than reducing the amount that the valves open, unless adding a turbo as Purebred says.
Lower compression means less efficiency, more heat, and reduced power all the time. Less air flow from more restricted intake means that more power will be lost at higher RPM. If the vehicle uses MAP, it could need reprogramming or risk running too rich at high RPM. But lower RPM performance wouldnāt be affected so much. Seems like a better way to go than reducing efficiency.
You are overthinking this. Every engine wears over time, and the programming in a stock PCM is designed to compensate for this. Also, as recently as the 1990s, many vehicles had non-interference engines with lower compression than is used todayā¦and they ran fine and performed adequately.
But the amount of air that it takes in at a particular speed and manifold pressure would be about the same no matter how worn it is. A worn out engine has more blow by, but that happens after the intake closes.