EGT and Boost Gauge on diesel turbo

[phs]

on idle it will read - something as soon as you give it gas it will go to +

on idle the motor is sucking air the turbo is not tuning enought to make positive presure.
once you apply gas it spuls up spinnig faster and faster. positivly force feeding your motor air so much that the once vacume becomes positivly charged
thats how it works with petrol motor,

i do know that you shouldnt fit BOV's to diesels for the fact you dont want to lose that built up presure, so maybe diesels start close to positive presure dunno im sure some can explain better for how it works on diesels.....?

[tommy222220_0]

Originally Posted by craig_nav

So if i did put a boost gauge on the nav, The gauge has vacume and boost... The diesels dont produce vacume so what would the gauge say?

Will only operate in the 0 ~ 15psi range. (15psi is roughly stock, aorund 17psi with an exhaust) Also most boost gauges come with a 4mm tee, otherwise most auto shops stock 'em for a few $.

The EGT is the main gauge for a diesel. It will let you know if the engine is running to hot (to much fuel) and is in danger of damage. Yes they may be pricey, but so is a new engine.

here's my install (also '05 STR)



With a few mods you can make the Zd30 much more reliable.
Gauges (EGT + boost is all you need)
A good quality catch can in conjunction with the EGR blanking mod will stop the horrible sludge that fors in the intake (exhaust gas + oil = Yuk)

[craig_nav]

Lol thats what i was thinkin would happen.. Where abouts did you tap the boost gauge in? I was looking at going in the boost sensor pipe that runs straight from the plenum.. With the EGT gauge sender, do you drill a hole and weld the nut for the sender on?

Also where abouts did you get the gauge cups for the pillar? I ordered a full pillar with the cups moulded in, not cheap lol...

Blocking the egr valve too, Is that the 2 pipes that come out from the left side about middle?

[Jarh73]

Originally Posted by craig_nav

Lol thats what i was thinkin would happen.. Where abouts did you tap the boost gauge in? I was looking at going in the boost sensor pipe that runs straight from the plenum.. With the EGT gauge sender, do you drill a hole and weld the nut for the sender on?

Also where abouts did you get the gauge cups for the pillar? I ordered a full pillar with the cups moulded in, not cheap lol...

Blocking the egr valve too, Is that the 2 pipes that come out from the left side about middle?

Craig did you find the hose coming off the actuator on the turbo?

EGT goes in the exhaust system 80 to 100mm from the turbo flange to ensure the probe does not interfere with the exhaust gas flow and to ensure an accurate temperature measurement.

Ideally you weld a nut onto the exhaust and screw the probe in but there are systems that use a hose clamp set up so you only have to drill a hole, no welding required.

Check ebay as they usually have kits for sale.

If you are feeling up to it blocking the EGR will make a big difference to the drive-ability of the car. Well worth it in my opinion.

Cheers

Justin

[Jarh73]

Originally Posted by phs

i do know that you shouldnt fit BOV's to diesels for the fact you dont want to lose that built up presure, so maybe diesels start close to positive presure dunno im sure some can explain better for how it works on diesels.....?

Diesels don't have a throttle plate so you don't need a blow off valve.

BOV is for when you close the throttle on a gear change to prevent excessive pressure build up before the throttle plate.

No throttle plate on a diesel so therefore no pressure build up when changing gears.

Cheers

Justin

[craig_nav]

Originally Posted by Jarh73

Diesels don't have a throttle plate so you don't need a blow off valve.

BOV is for when you close the throttle on a gear change to prevent excessive pressure build up before the throttle plate.

No throttle plate on a diesel so therefore no pressure build up when changing gears.

Cheers

Justin

This engine has a butterfly where the air goes in above the engine,I put a bigger air filter on mine and when i take my foot off quick after spooling it makes a wooosh sound.. But yeah i dont think the hold enough air in the pipes to have a BOV... Could work tho

[craig_nav]

Originally Posted by Jarh73

Craig did you find the hose coming off the actuator on the turbo?

EGT goes in the exhaust system 80 to 100mm from the turbo flange to ensure the probe does not interfere with the exhaust gas flow and to ensure an accurate temperature measurement.

Ideally you weld a nut onto the exhaust and screw the probe in but there are systems that use a hose clamp set up so you only have to drill a hole, no welding required.

Check ebay as they usually have kits for sale.

If you are feeling up to it blocking the EGR will make a big difference to the drive-ability of the car. Well worth it in my opinion.

Cheers

Justin

Yeah found the hose, Ill be hooking it all up this weekend hopefully, With the EGR idea. I have a faint idea where it is but not too sure,, Is it where the rusty metal pipe meets the alloy pipe on the lower left hand side of the engine,, And do u just put a shim or something alike between the 2 pipes to stop the exhaust gas coming back up to the intake? Thats my idea of it anyway lol, Is there pictures of this?

[phs]

Originally Posted by Jarh73

Diesels don't have a throttle plate so you don't need a blow off valve.

BOV is for when you close the throttle on a gear change to prevent excessive pressure build up before the throttle plate.

No throttle plate on a diesel so therefore no pressure build up when changing gears.

Cheers

Justin

now it makes sence....

with the EGT on a diesel motor the what area of the exhaust would you want the reading from ?

the dump from the back of the turbo can get very hot. but is this the area you want to read of further down where you can better readings of the exhaust fumes not the direct heat from the turbo charger?

Crag nav.

the ones iv seen have had a hole drilled and a thread like a nut welded on. then the probe screwed into it.

dunno if they make couplings that you could just drill a hole and you put them on and tighten the bolts either side and screw your probe in?

[Jarh73]

Originally Posted by phs

now it makes sence....

with the EGT on a diesel motor the what area of the exhaust would you want the reading from ?

the dump from the back of the turbo can get very hot. but is this the area you want to read of further down where you can better readings of the exhaust fumes not the direct heat from the turbo charger?

There are various schools of thought but the most common/easiest position is after the turbo on the dump pipe. There is a compromise between too close to the turbo; accurate temp reading but blocks exhaust flow, and far away from the turbo doesn't block the turbo but temperature measurement is very poor.

The 80 to 100mm from the turbo is ideal, minimal interference with exhaust flow but excellent temp measurement, but on many catalytic converter diesels this may not be possible as the CAT sits very close to the turbo. So you end up having the probe a bit too close to the turbo than ideal but it will still be fine.

The EGT temp basically is a heads up that your turbo might be heading for a meltdown and all other things being equal you pistons as well. It also helps to diagnose a range of engine issues.

Cheers

Justin

[Jarh73]

Thread for Probe that I MIG welded onto the Dump Pipe



Dump Pipe Installed



Digital EGT Gauge



Hope that Helps.