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str8upclownen said:
not really wouldn't a custom 3.2mm headgasket do the job? and with the thicker headgasket means you could safely turn up the boost :)
To get it down to where the stock turbo is would require a 2.4mm headgasket and I'm sure you could have one made. It will hurt quench though having the piston that far from the head. Not a deal killer but I bet you loose a little power and it may hurt the longevity of your engine. Not by much, you wouldn't even notice the power loss with the turbo on there.

Here's the point though, the stock 5sfe can already be taken up to ~15-16psi without race fuel depending on the turbo you use. When you drop the compression as you suggest that probably makes it good to ~16-17psi. So really it would only be worth it if you already had the fuel management to run that much boost and wanted that extra little bit. The mechanical limitations are only part of the equation. You have to get the right amount of fuel and timing to be able to use what you have. If you don't do that first then no matter how low your compression is your engine isn't likely to survive long.
 

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str8upclownen said:
what about upgraded pump lines and some nice 550s to take care of fuel? so you can even turn it up more then 16-17 with the headgasket?
The 5sfe fuel rail and lines are plenty for anything you can do to a stock 5s turbo or otherwise. The fuel pump should be upgraded though when you go past 200rwhp just to be safe.

You can't just drop bigger injectors in and expect your engine to live for very long. Even if you can find some 550cc injectors that are top feed and high impedance you are basically doubling the flow from what the stock ones were. That means at idle it will be starting at a 7.5:1 AFR and the O2 system will be trying to pull it back to 14.7:1. It might be able to do it but as soon as you go WOT, even with a turbo map sensor tricking it into thinking it is at a lower load, you will run insanely rich.

You must tune the fuel maps to match the VE curve of the engine with the turbo. This requires a piggyback or EMS. The only exception to that is if you use a ct-26 on a stock 5sfe with 315cc injectors, gen2 3sgte MAP sensor and you stay below 10psi. That only works because those components just happen to create a VE curve that is similar to the stock one. You also must consider something to tune timing but you can get away without it if you have a 93+ with the knock sensor and you run it on the rich side.

Do a search for 5sfte and turbo 5sfe. This has been discussed many times.
 

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Hey guys. I’m rebuilding a 5sfe with new mains and rod bearing and piston ring and full gasket set. Is there anything else that I should do internally for a turbo setup? I don’t plan on making a **** ton of power, maybe like 250 hp.
 
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