300tdi - where I'm at with a few questions.

[phibbzy]

Hi all,

Not sure if there is a lot of interest because its all been done before but I'd like to share some progress with my blunderbuss and perhaps put some information out there for comment.

Following a shagged radiator it was taken of the road for a month. In that time the chassis has been painted, sound deadener applied underbody, various bolts replaced and chequer plate installed in "high risk" spots.

A new Britpart alloy radiator went in to replace the old copper core which had seen its days and a nice shiny Allisport intercooler installed. I'd like to replace the britpart with an Allisport soon, coin allowing, but for the now the britpart is doing an "okay" job.

I recently had issues with the earth, making me think there was an overheating situation which, thanks to help on this forum, was resolved.

Last Sunday I had an auto electrician mate over who has assisted with the proper install of a tacho, water temp gauge & sender, boost and pyrometer - all VDO.

Those of you who have installed a pyro gauge - I cannot get a definitive answer on this! Pre (EGR plate) or post turbo (dump pipe)? What about two pyro's pre & post?

I have settled for the EGR plate for now due to simplicity, aware that the readings may well be out so I have allowed a min of 200 degrees - so 500 max in my eyes - when tuning. Until I have a definite scientific reason of WHERE it should be placed for the most effective reading.

I have performed the alterations on the Bosch IP, turned the fuel delivery cone 90 degrees and the star wheel 1 & 1/2 turns (both clockwise).

I'm hoping my tune is safe but open for input..

This was laboring up a medium hill in 3rd/4th...

Pre tune
EGT topping at 455
water temp 91 degrees
Unknown boost

Under a full load situation (110kmph, 4th gear, 2km long steep hill, giving it the berries.)

EGT topping at 510 degrees
Water temp 93 degrees
Boost 21 PSI

I'm yet to get used to the different sounds. To be honest, having power similar to my run about Camry is daunting. I'm convinced something is going to explode at any minute.

I'm a long way from "finished" in my eyes, but progress is nice

Happy for any input, critical or otherwise.

[steveG]

In the EGR plate where you have it is the best place.

Best way to illustrate is it's like putting the kids in the bath and turning on the hot tap. Would you want the temp gauge before it gets to them, or in the drain pipe
Consider the turbo as one of the kids - you want to know the heat you are subjecting it to.

Steve

[phibbzy]

In the EGR plate where you have it is the best place.

Best way to illustrate is it's like putting the kids in the bath and turning on the hot tap. Would you want the temp gauge before it gets to them, or in the drain pipe
Consider the turbo as one of the kids - you want to know the heat you are subjecting it to.

Steve

When the pyro is located on the EGR, would you expect the temperature post turbo to be higher or lower?

[steane]

You don't need to add 200 degrees to the reading if you use the EGR plate either, only if you take the reading after the turbo.

21 psi boost seems high to me for a 300tdi. Can blow head gaskets running too much boost, I think the safe ceiling is around 18 psi, if you want it to last.

[phibbzy]

You don't need to add 200 degrees to the reading if you use the EGR plate either, only if you take the reading after the turbo.

21 psi boost seems high to me for a 300tdi. Can blow head gaskets running too much boost, I think the safe ceiling is around 18 psi, if you want it to last.

Thanks.

21 wasn't really my choice. I put the IC in, tweaked the pump and there it sits. It may well have been running that the entire time but I only recently acquired a boost gauge.

I'm guessing fiddling is required on the actuator to reduce it?

[steveG]

Don't worry about what temp is after the turbo - its waste..

Just watch the EGT's carefully if you start reducing the boost. In general more boost usually results in lower temps for the same amount of fuel.

At 510* pre-turbo you've got plenty to play with in terms of EGT, but be aware that 110kmh in 4th in an unloaded vehicle probably will be cooler than 50k's flat out towing something heavy.

I've found when playing with the fueling on the isuzu, that towing our camper I was getting easily 50* or more higher than anything I could achieve unloaded.
I think part of the issue is heat soak - when heavily loaded you run hotter even on the flat, so as soon as you point it at a hill you're starting from a higher baseline.
So just watch the first few times you are loaded up, otherwise it could catch you out.

Steve