EGT's?

[Hombrey]

Guys have a turbo fitted to my TD42 and just fitted the egt probe and boost guages. Probe is pre turbo and running max 10lb of boost at present and looking to increase that to a max of 15lb. 1/2 turn of the fuel screw so far and took for a test drive. EGT's foot down on the flat will climb to late 500's before gear change then drop right back. Cruising they are about 300 max. I've read the info about max egt's of like 550 - 650 but are you guys getting that cruising or spiking? Have read about guys running 15lb and a full turn of the fuel screw but am reluctant given I can already spike EGT's to 600c at 1/2 a turn? What set ups have you got - Boost, fuel setting and resultant egt's? BTW am on 33's in a Manual.

[Swamped]

Search bar is your friend.

Theres a bit here.

http://www.offroadexpress.co.nz/Forums/viewtopic.php?f=25&t=19196&p=234325&hilit=td42+turbo#p234325

[Hombrey]

Hey thanks. i have had a read of a number of the previous posts but was just interested to see what others actually ended up settling on and what egt's they get under normal driving conditions. Now wound boost to 12lb but thats not changed egt's at all and run out of actuator rod thread!! . Can get to 600 under hard accelleration 3rd to 4th.

[jA-]

just remember that no 2 injector pump are going to be the same just coz one guy turns diesel up one turn doesnt mean you will be able to do the same

Also the more boost you run the lower your egt's will be eg. so if you can get 15psi with out turning the fuel up your egt's should get lower

the best way to adjust your boost is with a boost tap as well adjusting the waste gate rod will cause the waste gate to fail in time.

i run up to 20psi and no more than 600 egt anytime, cruzing i get 300-400 depending on road/wind etc

Jacob

[niblik]

have a fitted the egt probe pre turbo

this'll give false/inaccurate egt's...

[kbushnz]

have a fitted the egt probe pre turbo

this'll give false/inaccurate egt's...

Pre turbo (in the manifold between head and turbo) will give the most accurate EGT's

Its the real temp comming out for your engine....

If you drive to those you cant do any better.

Most people tend to put it post turbo or in the exhaust dump pipe as its the easiest...This can give you false or lower readings or delayed readings.

Calvin

[niblik]

my bad.. read it wrong with kids hangin off me.. lol..

i've done the same..

as you were..

[sibainmud]

Try this thread. It's dealing with the TD42's little brother, the TD27. Same thing apply.
Mine has never gone over 550 deg C.
Can't get clutches to hold the horse power now thou.
Bloody small TD27 clutches
http://www.offroadexpress.co.nz/Forums/viewtopic.php?f=46&t=20868&start=15

Cheers.

[Swamped]

Took a while to get an answer in that thread eh...

[sibainmud]

Took a while to get an answer in that thread eh...

Should of read the first thread
Doh, Sorry.

[Hombrey]

Crikey I'm pleased I was'nt on my last legs....still patience aye!!. Ok thankyou to those who have posted to my April question....WOO HOO. Go me. So have not changed anything. Pleased the probe is in the right spot. Basically just drive to the EGT guage. Still though think I'm missing something as hear plenty of BIG stories about running say 13lb with half a turn or so and trucks like mine being "wicked fast". Well my ole girl is much better with the turbo but I'm not scared of the power quite yet. Maybe a decent tune and new injectors might help a bit. Also have a water to air intercooler set up ready to add which I'm hoping will help keep egt's down a little. BTW my probe is only like 3mm so if it spikes to say 600c I suspect its heating up way faster than engine components. And it is directly into the manifold right in front of port 3 so cops worst case heat I suspect. Its VERY sensitive and the guage is quick to move. Thanks for the posts guys.

[zookfest]

my old girl running 29psi and seems to get to 550-600 im thinking about intercooling it,mate of mine with similar setup added one and on road to coast dropd temp by 50-100

[Shane]

Crikey I'm pleased I was'nt on my last legs....still patience aye!!. Ok thankyou to those who have posted to my April question....WOO HOO. Go me. So have not changed anything. Pleased the probe is in the right spot. Basically just drive to the EGT guage. Still though think I'm missing something as hear plenty of BIG stories about running say 13lb with half a turn or so and trucks like mine being "wicked fast". Well my ole girl is much better with the turbo but I'm not scared of the power quite yet. Maybe a decent tune and new injectors might help a bit. Also have a water to air intercooler set up ready to add which I'm hoping will help keep egt's down a little. BTW my probe is only like 3mm so if it spikes to say 600c I suspect its heating up way faster than engine components. And it is directly into the manifold right in front of port 3 so cops worst case heat I suspect. Its VERY sensitive and the guage is quick to move. Thanks for the posts guys.

I would try running more boost(16-17psi) see if that brings the egt down.

Fuel generates high EGT,to bring the exhast temp down you need to add more air(boost)

Guys that run big pumps(shit loads of fuel)have boost up round 28-35psi mark.

600c isnt that bad if under load up hill or something like that.

EGT probe measures exhast gas not the Exhast mainfold it self,they do change quite quick,I was surprised when I first fitted mine.

What turbo do you have?
How much boost do you have at 100kph?

Shane

[tweake]

however what you have to watch is inlet air temps start to get to high around 15psi. if your running 15 psi you really need to intercool.

[Hombrey]

I'm running about 13lb of boost max at the moment. at 100k boost is about 3 - 4lb. System is a turbo glide kit from Aus but uses a garret turbo. not sure on the specs but could dig that out. Yeah realise the probe measures gasses and suspect mine being a small probe in the manifold right in front of an exhaust port is probably providing about the most extreme gas temp of anywhere but prefer to know worst case temps. Turbo is providing good power to about 3300 revs now and then I suspect is starting to run lean on fuel because before I wound up the fuel peak power was to about 2800 revs so 1/2 a turn extended the power rev range about 500 revs. I hear lots of talk of 4000 and higher revs out of these presumably with good power and EGT's so if thats true mines missing something that I need to sort.

[Swamped]

I havn't looked into this for a while so I might be wrong....
Have you got a boost compensator (or whatever they are called) on it for fueling?? I would expect it to be rich low down, normal mid range and leaning out up top if you don't have one. It smoke much at lower revs??
Without one it would be a balancing act as far as mixture goes and you wouldn't be getting the best performance.

[sibainmud]

Let me explain my position on this
I'm a Marine diesel mechanic, and have been for over 20 years.
A boat engine falls into the category of stationary engines and are subject to constant load and temps. Think of them like a car/truck going up a hill in top gear constantly. With boats the balance between performance and economy is vital with the emphasis on reliability. One difference cars/trucks has is they have variable load due to inclination of hills and a gearbox with multiple ratios.
While I don't consider myself an expert, my back ground gives me a bit of insight into this subject.
You keep referring to turning fuel screws 1/2 a turn etc, that doesn't mean jack. Every fuel injection pump is individual and no two are the same, it's just the adjustments made by the fuel technician that make them perform the same.
There are some basic rules when it comes to getting higher performance out of a diesel; streamline air in (even forced) and exhaust out with a bit of fuel thrown in to get it all going.
Getting the right balance is a bit of trial and error. A EGT (pyro) gauge helps with this process. Resist getting more rev's out of the engine because that always end in tears
Concentrate on the usable rev range (1500 to 3500).
Not getting at you but, you have asked for advise and then argue it. These guys are bang on the their advise and some of them have even been down this track before.

Just my 2c worth.

Cheers,
Simon.

[DieselBoy]

Some good info in this thread!!!

Its very tricky to explain.

The basic idea behind tuning a Turbo diesel is to get the best and most complete burn of the fuel being supplied.

It is very hard to do this properly with out a boost compensator aneroid on the injector pump.

BUT, the the same principle still applies, even for you dodgy fuel screw winders

Disconnect your waste gate.

Why??

Because you want to be giving the engine the maximum amount of air you can, all the time, to promote the best burn of the fuel being supplied, which = POWER .

Instead of controlling your boost level with the waste gate, and allowing precious boost potential to escape, you control it with the fuel delivery.

You want to dial in just enough fuel for your turbo to make your desired boost pressure. I would say that 15psi at 2500rpm is heaps (thats what mines running anyway). It will probably run out of fuel close to the 4000rpm mark and the boost pressure will start to drop of as the rev's increase past that.


This gives you the best burn, so therefore no over fueling and the lowest EGT's. You can keep you foot up it all the way to the top of the hill, as its getting a nice clean, lean burn and not creating excess heat through over fueling and pumping out black smoke.

The catch is that with out the boost compensator on the injector pump, it will over fuel and blow smoke down low in the rev range.

Combine what I said with Sibainmud and jA- and the others and you'l be sweet

[sibainmud]

Bingo

Hard to explain.
We all on the same page
If no compensator then lift your foot till boost comes up

[Hombrey]

Thanks guys and I'm not arguing any of the info you are providing. i do get exactly whet you mean about fuel mix, boost compensators etc and lean and rich etc. i will reread these posts to ensure I've got my head around what your advising me and will then try it out and see how the truck runs. Thanks you all for your experience. Much appreciated.