Outer Limits 4x4 Board

i have just finshed piping up my intercooler and the boost has dropped 1psi which i thought is great cos its fron mount. my question is what i nee to look out for in tweakin the boost. it runs standard at 10psi and when i disconnect the wastgate hose it runs 16psi . what is a safe bost pressure without the egt's goin through the roof.?? and blowin the turbo

by the way its a 2003 hilux with a 1kz-te engine if that helps too

Just roughly EGT's go down with boost, (unless the turbo is streched and the outlet temps are high) and up with fuel.
Some pressure drop across an intercooler is essential if it is cooling the air, what goes in hot comes out cooler, which means denser, as the amount of air hasn't changed the pressure therefore must drop.
I suggest you get a pyro, make a suitable mount for it, preferably prior to the turbo where the exhaust collects and run up and down a big hill with a trailer on,(or get on a chassis dyno if you have one ) If the temp starts getting to 550 degrees C loose some fuel, if at any time removing boost drops EGT's then the turbo outlet temps are too high and you should remove boost and fuel.
Joel

disconnect the gate and run it to the inlet manifold, so it senses at the motor after the cooler...

You can adjust the boost by shortenting the actuator rod, this also reduces the travel of the actuator and can in some instances cause boost spikes. You can fit an adjustable bleed in the actuator hose and bleed off some boost until the desired intake boost is acheived, this can also lead to unstable boost in some applications but not likely in your case, more big HP stuff with big turbo's.
Joel

your more likly to run into the fuel cutoff. i would use a boost controller so you can get closer to cutoff point without accidently going over it.

i wouldn't recommend fitting the gate and connecting it to the inlet manifold. any leak in the hoses/intercooler will mean the turbo will over rev before you could notice it.

your intercooler will help keep the EGT's down and uppin the boost a bit won't hurt.

so is what your sayin that my egt's wont go up by adjusting the boost?

i cant up the fuel without gettin a dpchip which is expensive as, so its just the boost i was gonna tweak to about 13psi . i have been told that the only thing that suffers from tweakin the boost is the turbo cos it has to work a bit harder is that true or can i do damage somewhere else.

i doubt it will go up at all, mainly because of your intercooler.

the only thing i would do is to make sure the EGR is blocked off and if need be disable the butterfly (sorry not sure of the butterfly system in those).

the only real downside is the turbo revs more, however it should still be withen a resonable rev range. as long as its in ok condition it shouldn't hurt it.

Because you have an electronic fuel system, there will be a limit of boost pressure before the ecu sees an overboost problem and puts you into a limp mode or switches the check engine light on. Raising boost will work before this limit as the ecu says more load or air consumed so more fuel is added.
Yes to go further you will need a dp chip or something to up the fuel.....ther eare no real shortcuts for you.


Egts under load should get no higher then 550c....yes more air in a diesel will drop egts down as long as your are within the efficiency zone of your turbo.

Andy

i didnt think the egt's would go up much cos of the intercooler i can tweak the boost cos the air is colder. thanks heaps i will tweak it to 12 or 13psi and leave it i dont think i will get a dpchip or boost it heaps , as much as i have heard they make a difference i dont have 1300 buck lyin around.