Outer Limits 4x4 Board

I have a turbo, intercooler and boost compensator on a 1HZ 105 landcruiser installed with 55000ks now with 85000ks. the problem is that the max - 85%+ torque isn't coming on until 2500+rpm. It is a DTS turbo with an air to water intercooler. looking around the torque should be at 85% at around 1800-2000rpm . What can be done is it worth pulling off the compensator... are they a waste of time? I have been told to loosen the spring rate on the compensator and loose a little top end power

leave it on. It will allow you to have the max fuel adjusted higher without being really smokey low down.
The boost compensators have three different adjustments as well as the max fuel screw on the pump. all adjustments need to be correct as they affect each other to a degree. It is tricky tuning them.
You shouldnt have to lose any top end, with the boost compensator, you should be able to get a pretty smooth power curve right up to redline

Have a read through this link http://www.lcool.org/technical/80_serie ... p_adj.html, it will be more or less the same on your 1hz

Thanks 80's_delirious,
but does this reduce the torque curve it currently looks like at skate boarders 1/4 pipe from 2000 -2500rpm. the lcool site doesn't say enough

What turbo is on it, and what a/r does it have on the exhaust...........

The Lcool info is used by lots of people, it is a little hard to get your head around for sure.

If its tuned correctly it can make a huge difference to the torque curve.

The boost compensator allows you to increase the main fuel screw setting because it reduces the amount of fuel being injected when the engine is not under boost.
Without the boost compensator, to get max performance when under boost, the engine would run very smokey at idle or when no boost.

You can adjust the boost compensator to fine tune how much fuel is injected when there is no boost so you dont have a smokey idle, but also so there is enough fuel available to give it punchy response when you step on it.

If you are handy with the spanners, it is worth having a crack at the Lcool tuning tips. Just adjust things in the order listed and do small adjustments. also its a good idea to keep a notebook and write down what you change each time you change something, it is easy to lose track of what you have done.

Do you have an EGT gauge? (exhaust Gas Temperature)
It is very easy to increase the fuel to a level that can cause engine damage. An EGT gauge lets you keep an eye on it so you dont wind things up too far.
1HZ's do not like to be overfueled. Too much fuel in a diesel produces a lot more heat, the heat will do damage.


A couple of tips.

Take it to a professional, or be prepared to fiddle, and fiddle and fiddle some more

[b[Boost compensator characteristic tendency[/b] (toothed wheel inside top cover, under the diaphragm)
I found this hard to adjust one click at a time. it is dificult to get at and takes a bit of effort to get it to move. I found it easier to adjust by taking the top cover off and carefully lifting the edge of the diaphragm to adjust it. be carefull not to rotate the diaphragm.

Maximum off boost injection volume (screw and nut on top cover)
use a scriber or shar tool to mark the top of the screw and the cover so you have a reference point to keep track of how much you have adjusted it.
If this setting is on the lowest setting, a half turn will take it to the maximum setting. a full turn will take it right back to where you started. small adjustments at a time are the go, say 1/8th of a turn or less.

Boost Compensator Profile(under the top cover.)
use a white paint pen to mark the position of the diaphragm and the housing so you have a reference point for where you started.
this is similar to above. a half turn will take it from minimum setting to maximum setting.
again, small adjustments make big differences, too much here can see you producing very high temps.

Some of these adjustments might already be on max. If so, you can increase the main fuel screw slightly (again 1/8th turn at a time) and reduce some of these adjustments

flyology wrote:What turbo is on it, and what a/r does it have on the exhaust...........

It is a dts turbo with a mercury 3inch exhust