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EGT and Boost for 300TDI

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Hi Everyone,

I want a little more performance from my 300tdi Defender.

I have bought a gauge to monitor EGT and Boost which has programmable alarms.

This is fitted with a boost pin and timing spacer (These are the only mods).

So some questions if you don't mind because I'm struggling to find definitive answers:

1. Am I right that the EGT alarm should be set to 750 degrees C? It will be fitted in the EGR blanking plate.

2. As it has a boost pin to take advantage of the extra fuel I understand I need to up the boost, what should I set it to?
I think the Defender runs 15psi as standard and a Discovery runs 18psi as standard, if that's correct could I go to 20psi and will a 300tdi be ok with that? I could then set the alarm on the gauge to 21psi? Or am I way off with those figures?

3. How exactly do I adjust the boost, from what I can see it seems to suggest removing the pin and winding the rod towards the bulkhead. What I can't understand is how to get the rod back into the pin if it's shorter! Sorry I'm probably being really dim but I need some step by step instructions please.  

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Ok thanks but I'm still a bit confused, to get more performance from a diesel I thought you needed more fuel and air?

That article suggests giving more fuel but leaving the boost at 18psi.

So is it saying the 300tdi won't live long with more than 18psi? Anyone running more that could comment good or bad? 

I'm also still not sure where to find a document on egt temps for a 300tdi, does anyone have a source please? 

Many thanks, 

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Regarding egt there is little actually published regarding figures but research I've done found that the general upper temp for working is about 750 degrees centigrade,  it's good up to that but you generally don't want to run it that hot for any duration.

To increase the "boost" pressure you need to shorten the actuator linkage, this effectively allows less exhaust gas to "flow" through the exhaust turbine relief valve thus more gas flows through the turbine instead - which drives the compressor faster = more air in.

The way land rover set the engine up in the first place allows you to only need to adjust the fuel side to get an initial improvement in "performance". If you then want to further that then you want to look at other aspects like the inlet side I.e adjustment of the boost etc.

Start googling more, there are heaps of topics throughout verious LR forums giving experiences of people doing this.

Mav

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16 hours ago, Defender said:

Ok thanks but I'm still a bit confused, to get more performance from a diesel I thought you needed more fuel and air?

That article suggests giving more fuel but leaving the boost at 18psi.

So is it saying the 300tdi won't live long with more than 18psi? Anyone running more that could comment good or bad? 

I'm also still not sure where to find a document on egt temps for a 300tdi, does anyone have a source please? 

Many thanks, 

I have read mixed reports on increasing the boost on TDIs. From what I gather, without the large intercooler, it is not doing the engine (or turbo) any good.

This company has been around for many, many years, and does not recommend touching the turbo pressure unless you change the turbo for the stage 2 version:

http://www.allardturbosport.co.uk/index.php?page=Defender-and-Discovery-200-300-TDI

Also, the boost pin does nothing to improve your power, it just allows more fuel to be injected momentarily under acceleration. The max fuel delivery of the pump does not change.

I have removed the function of the boost pin by winding the screw in completely. Turbo pressure is unchanged as is fuel delivery. It just means if you put your foot down, your fuel delivery only depends on throttle position and RPM, rather than Throttle pos, RPM and boost. I am very happy with this setup. I want the engine to last for a long time, so any other mods are not really an option for me. 

Daan

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20 psi is safe.  Get a boost valve/controller to adjust it.  Do not fiddle with the wastegate rod.  It damages the actuator.

Nobody knows the safe temperature.  Garret specifies 720 C continuous limit for the turbo and this is certainly safe.

 

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3 hours ago, Red90 said:

20 psi is safe.  Get a boost valve/controller to adjust it.  Do not fiddle with the wastegate rod.  It damages the actuator.

Nobody knows the safe temperature.  Garret specifies 720 C continuous limit for the turbo and this is certainly safe.

 

Thank you that's exactly the type of thing I wanted to know. 

I'll look into getting a boost controller. 

Interesting information from Garret so I will set the alarm on the guage to that thank you. 

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5 minutes ago, Defender said:

Thank you that's exactly the type of thing I wanted to know. 

I'll look into getting a boost controller. 

Interesting information from Garret so I will set the alarm on the guage to that thank you. 

Give yourself leeway. Set the alarm at 700, then you know you are inside the safe zone

Also, don't do anything until you have serviced your injectors. Hot EGT and dribbly injectors = pistons you can see all the way through

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