7afe turbo, How long will it last Options

[nk_pimpin18]

my engine has 82k miles on it im planning on running 5-6 psi how long do you think it will last?

[carlosfandango]

This subject is of great interest to me, not just in terms of turbo, but in terms of forced induction in general for the FE and what that means to the internal design capacities in the head.

Oil blowing out the seals - ineficient thermal efficiencey causing excessive cylinder heat, causing excessive blow by positively pressurising the crankcase. Is the turbo water cooled and how are you lubricating the turbo bearings. Which method of PCV are you guys using?

My understanding of the FE head - (i'm here to learn not to ponitificate, so if i get my theories wrong, pleases help me out)

The FE heads were designed to have performance whilst being economical and meet emmissions standards. the narrow cams and lightweight internals help a quick rpm response, torque is smoothly distributed throughout the power band. The FE's are smooth engines, they like smooth increases of power.

These engines must not be confused with the 4EFTE, or the likes of a 4EFHE as they both have more aggressive cam profiles. The engines are designed to perform from a high performance point of view, rather than increased economy. Although the FHE is still an economy engine in principal, toyota's attempts to make the FE heads with more kick.

The GE series created by yamaha, are built to higher tolerances, can adapt to sharp changes in rpm, with the actual work being done in the head not hampered by the excessive heats and fatigue's this could cause the FE, because the head components are stronger by design.

Using a Turbo, if set up properly, will bring in peak torque earlier in the rev range, the amount of power in the power band will rise, torque will increase, i theorise that the stock smooth torque curve will be hampered by steps and dips, on and off boost.

Peak power in the rev range will also move closer to ecu rev limiter.

Running at 5psi will have it's issues, mainly getting the mass flow and charge temps right - thermal efficiency is the key.

trying to run any higher than that will negate the inbuilt characteristics and design limits of the head components and will cause eventual failure.

If i've missed anything, or if i've got my understanding wrong, i'd appreciate being shown me errors and why.

And for anybody willing to discuss this further, what effect would you suspose nitrous will have on the 7AFE, 50hp.

regards

Carlos