Increasing turbo boost

[EnviroImports.com]

Please be carefull when you are playing with your fuel boost and your turbo, you can have some fun, but before you do, you really should have a Pyrometer/ EGT meter,

Give this a little thought,
when your driving around , foot on the throttle your exhaust gas is spooling up your turbo, your turbo can get upwards of 1000*+ hot, so you have two sections of your turbo the exhaust side and the air intake side, Hot air does not make great boost, so an L300 really should have an intercooler put on it to drop those temps or a water injection system for the easiest and best of everything, but back to the turbo, 90% of the drivers of delicas will drive around pull over and shut off the engine, not giving a thought to what is going on in the motor.
so if your exhaust temp is that hot, how hot is the housing that holds the turbo fins/ blades, but most importantly is the Bearing
that poor little bearing in the center of the housing is oil cooled and water cooled in some, and the only way for it to cool down at a reasonable rate like it should is for you to either have a turbo timer so your motor will run for an extra set amount of time, they are easily set from 30 second incriments. a EGT/Pyrometer to actually show you how hot the turbo is, or just ALWAYS remembering to let the motor cool down before shutting it off.
Other wise that poor little bearing will sit in its oil and cook away until the temp slowly disapates, now this may not be an issue for the ocasional time you are in traffic, pull over shut it off not thinking about it and walk away
BUT these vans were at least 15 years old when you got them, and how many years of use and hard use has that turbo been spooling? and left to cool down on its own with out the oil pump flowing the oil past and letting the heat out of the turbo, This is Also a great reason to keep your oil changed every 3000-5000 km it also gets cooked pretty good escorting heat from your turbo, some L300 turbos also have water cooling, this also takes heat from the turbo, but does nothing if the engine is turned off.

keeping this in mind will help you keep your turbo happy for a long life.

[ubernub]

Please be carefull when you are playing with your fuel boost and your turbo, you can have some fun, but before you do, you really should have a Pyrometer/ EGT meter,

Give this a little thought,
when your driving around , foot on the throttle your exhaust gas is spooling up your turbo, your turbo can get upwards of 1000*+ hot, so you have two sections of your turbo the exhaust side and the air intake side, Hot air does not make great boost, so an L300 really should have an intercooler put on it to drop those temps or a water injection system for the easiest and best of everything, but back to the turbo, 90% of the drivers of delicas will drive around pull over and shut off the engine, not giving a thought to what is going on in the motor.
so if your exhaust temp is that hot, how hot is the housing that holds the turbo fins/ blades, but most importantly is the Bearing
that poor little bearing in the center of the housing is oil cooled and water cooled in some, and the only way for it to cool down at a reasonable rate like it should is for you to either have a turbo timer so your motor will run for an extra set amount of time, they are easily set from 30 second incriments. a EGT/Pyrometer to actually show you how hot the turbo is, or just ALWAYS remembering to let the motor cool down before shutting it off.
Other wise that poor little bearing will sit in its oil and cook away until the temp slowly disapates, now this may not be an issue for the ocasional time you are in traffic, pull over shut it off not thinking about it and walk away
BUT these vans were at least 15 years old when you got them, and how many years of use and hard use has that turbo been spooling? and left to cool down on its own with out the oil pump flowing the oil past and letting the heat out of the turbo, This is Also a great reason to keep your oil changed every 3000-5000 km it also gets cooked pretty good escorting heat from your turbo, some L300 turbos also have water cooling, this also takes heat from the turbo, but does nothing if the engine is turned off.

keeping this in mind will help you keep your turbo happy for a long life.

So what you're saying, is that i don't accually need a EGT gauge if i let it run on idle for like 1min before turning it off? :)
If i go back to normal fuel pressure but leave the turbo boost at 11,6psi, will it be ok/minimal risk of burnt valves and cracked head?

[nxski]

You'll probably still want to monitor your egt's for uphill climbs. You're using the gauge to make sure the engine is fully cooled down when you come to a stop but you're using it to make sure you don't overheat when you're climbing hills. I thought I could get away without one until I had overheating problems coming back from Princeton. I'd say it's one of the most important additions you can make!

[EnviroImports.com]

A pyrometer is the smart guy thing to put on , yes it will cost you some money , but destroying your turbo or other engine stuff will cost you a lot more

[thedjjack]

Even if you cool down your motor after....YOU NEED EGT if you are going above factory settings...

Plus it is really hard to cool a motor down if there is a hole in the piston from exceeding melting temperature.

I am surprised how hot I can get my EGT with stock settings with loads on climbs..

[davidwwc]

After people installed an EGT gauge , they mostly change their way of driving. What it means is that they have been driving with their foot a bit too heavy but which did not show up with the stock gauge like the temperature gauge. When the temp. gauge shows up ,it could be quite late ..

Cheers,
DC

[yojimbo]

Guys you don't need an EGT to let the turbo/engine cool down at journeys end, the reason for letting an engine idle is not to cool it, though its probably beneficial to let the heat balance out in the block and head a bit, it's because the turbo is still potentially spinning at very high revs, and if you shut the motor down you remove the oil supply from the bearings and it can spin down with no oil pressure and kill the turbo. Whats the turbo rpm? 100k? That can take a few moments to slow up.

Also, while there are real concerns with high boost pressures, this thread is about returning to stock. As it happens I want to do the same, I'm limited to .6 bar right now, I'm going to double check the value with a different gauge just to make sure, but I expect I'll get a new wastegate, there's a japanese supplier on ebay selling replacement for less than £50 shipped.

As an aside, are there any reports of a 4d56 head or gasket failing due to purely age? My motor is a 1994, cooling system in excellent condition, and I don't drive it hard, the 4m40 seems to have a high failure rate even when looked after, but I don't get that vibe on the 4d56, any comments?

[tiitus]

I think at mine delicas boost is now about 1bar, my bottom say that.
I have to make a gauge installion, then I'm sure. It has been almost
year now ok. But I have many pajeros which have over 1bar boost.
If you make these high boost 4D56 engines, you need a big intercooler and
better intake/exhaust (3") and lot of brains.

Those 33" big tires need a lot of power.

[EnviroImports.com]

this pic is from a L400 I did up, but the idea is the same, you can have your pyrometer and other gauges and have them look good, if your going to make the investment in a diesel motor and expect it to last for many years, you need to take care of it and a few hundred dollars to have an eye into how your engine is running is money well invested.

[jessef]

if your going to make the investment in a diesel motor and expect it to last for many years, you need to take care of it and a few hundred dollars to have an eye into how your engine is running is money well invested.

quote of the year

[definingdigital]

Hello everyone!
I wanted to increase the turbo boost on my L300 2.5TD and found some instructions on how to do it.
I installed a boost gauge, and tested the stock pressure before adjusting. It turned out to be 0.6bar / 8.7psi, which is very low since factory boost is 12psi!
I tried to adjust it up by tighting up the wastegate rod screw, but im not gaining any more boost.
What am i doing wrong?

I'm dealing with the same kind of situation. After installing my boost gauge, it was reading 8-8.5 max psi, then I did some small adjustments and then I'd go for a drive to see how high the boost was going, but it kind of maxed out at 10 psi, kind of bumps a bit over 10psi, but nothing else. Even with more turns on the adjustment nut.

So here's my question: What happens if you turn the nut past the max point but don't get any additional boost? Does this still mean the turbo is working properly? Shouldn't it be able to go higher? Is there any potential for damage if the adjustment screw is set too far even if you're not getting the boost?

[definingdigital]

Just thought I'd mention something else I noticed when making adjustments for increasing the boost... I think the reason why my boost wasn't actually going higher on adjustments was because I wasn't re-locking the nuts after each adjustment. I put a little dot on the adjustment nut, (I find it helps with adjustments to know how many rotations etc.) and I noticed that after I made an adjustment and went for a drive, when I came back the position had moved. Probably due to vibration. So this could be why my adjustments seemed to stop giving me any increase in boost.

I have it set at 10psi right now, I wanted to do some test runs for a performance comparison. So just be careful when adjusting this, and maybe make sure you tighten the lock nuts for each adjustment. It will probably give a more accurate reading for increases.

As for slugging up hills, the van still seemed to be chugging up the malahat this weekend, I'm going to change the air filter to a K&N and then re-test to see any improvements before I increase the boost some more. Will update if I find anything that might be helpful for anyone else.

Cheers.

[bionic]

you will only see an increase in boost if there is extra fuel to burn. You are looking for an efficient balance. The fuel pump adjustment will net more fuel pressure, which will increase your boost...the wastegate adjustment will control the burn of that fuel. (the simplified version)
Be very careful when adjusting the pump pressure...extra boost will certainly mean higer EGT's which are your enemy!
A Pyrometer is paramount when attempting to maximize your engines potential. Boost is only half the story.

[yojimbo]

you will only see an increase in boost if there is extra fuel to burn.

That's the function of the injector pump diaphragm, to increase fuelling to match the boost level. Or you can increase it for more fuel generally or be more responsive to boost pressure by adjustin the spring preload etc etc. Mechanical pumps are fun!

[definingdigital]

so do I need an air/fuel ratio gauge to see how the fuel is balanced with the adjustment on the wastegate? I thought most guys on here had just done the adjustment on the wastegate to get more power. What should be my next step to get the right balance?

I have a boost and EGT gauge already installed. And what's the warning/slow down range for exhaust temp with the sender POST turbo? I did a search but the numbers were all over the place.

cheers