Boost and EGT gauge (2 Viewers)

[IanB]

Fair enough, but that is just one example out of millions of vehicles out there on the roads worldwide. Those odds are good enough for me to believe the manufacturers in most cases.

Again, I am strictly talking about driving a vehicle in its straight from the factory form. Make changes to a vehicle and all bets are off.

I drove my Hilux Surf and 2X HDJ81's home through the mountains, bone stock powertrain wise, with no gauges. If the hill was slowing us down, apply more throttle.

Now that I have the gauges, and can see what's going on, I shudder to think how hot things got due to my ignorance. Having the gauges has definitely changed the way I drive these diesels, it's a real eye opener.

 

[Highmesa]

Trying to instrument a 91 HDJ81 for the first time and looking for lessons learned and suggestions.

• Gauges looking at HGSI, they have a 4 channel digital(round) or a single channel mini digital, rectangular. Suggestions?
• EGT: several posts up was a recommendation for EGT probe upstream from turbo. Manifold tap, or is there a port I have not found yet? Where is the sweet spot? It seems you might get more of one cylinder vs post turbo. From the other EGT, TGT, TOT days it was all about calibration and knowing what temps you were looking for.
• Boost: HGSI only has a pressure transducer I do not think will hold up to the temps, but it would be digital. It came with a direct pressure, T'd into the existing line off the cross over manifold, I don't think it is accurate. T in ok or new tap?
• TOT: at the manifold inlet, for the hopefully soon to be acquired Intercooler ?
• Trans: Several options for the temp probe Lessons learned?
• What am I missing?

Thanks

 

[mudgudgeon]

There's pics here showing the best place for the EGT probe

Rolling the dice - slow moving turbo HZJ105 project

My preference for EGT gauge is an old school dial gauge. With a dial gauge, you can see with a glance what is happening, and you get used to where the needle will rest at your maximum EGT without having to think about it.
Digital, especially if it's a numeric display, the readout is constantly shifting, it takes a longer glance to get a reading.

The gauges I think are important to have visible at a glance are EGT, and engine temp. Boost is useful, but more of a curiosity.

If you have an auto, and are towing regularly, maybe add a trans temp.

 

[Highmesa]

Great, Thanks Good point on an analog

 

[BallVice]

Do those that have installed boost and EGT gauges on a truck with aftermarket turbo find them useful long-term after initial install and tuning?

boost is good to have
EGT is NEED to have - you can save your motor AND turbo life with your EGT -

I am a retired military pilot - TOT/TGT/EGT all were things we used in normal flight

 

[mudgudgeon]

boost is good to have
EGT is NEED to have - you can save your motor AND turbo life with your EGT -

I am a retired military pilot - TOT/TGT/EGT all were things we used in normal flight

For the dummies, what is TOT, TGT?

 

[mudgudgeon]

boost is good to have
EGT is NEED to have - you can save your motor AND turbo life with your EGT -

I am a retired military pilot - TOT/TGT/EGT all were things we used in normal flight

For the dummies, what is TOT, TGT?


Damn double post. No points for picking the dummy here!

 

[dousty]

Do those that have installed boost and EGT gauges on a truck with aftermarket turbo find them useful long-term after initial install and tuning?

Not if I tuned the engine for full load conditions. I would hit the beach and line up some massive sand dunes to tune max EGT. My wife isn't going to monitor these gauges and adjust her accelerator position. Once it was set up the gauges would come out and you drive it with peace of mind.

 

[dousty]

I also recommend fitting your gauges and driving for a month prior to making any modifications so you can see what is really happening with a stock engine. Some of the EGT figures that get quoted (on this forum and others) as maximums are exceeded by stock engines. Once you have a base line you can then tune to keep inside the standard peak temperature under the same conditions (including ambient!).

 

[BallVice]

For the dummies, what is TOT, TGT?


Damn double post. No points for picking the dummy here!

LOL - sorry - they don't apply here but:
TOT - Turbine Outlet Temperature
TGT - Turbine Gas Temperature

Not to be confused with TIT - Turbine INLET Temperature (which is a LOT hotter than EGT - which is measured at the OUTLET - FYI)

 

[gerg]

I tune my egts and boost as though Helen Keller was borrowing my truck to go skiing in Colorado for the weekend.

 

[mudgudgeon]

I tune my egts and boost as though Helen Keller was borrowing my truck to go skiing in Colorado for the weekend.

You disconnect the battery, and hide the keys to tune?

 

[ozwallaby]

LOL - sorry - they don't apply here but:
TOT - Turbine Outlet Temperature
TGT - Turbine Gas Temperature

Not to be confused with TIT - Turbine INLET Temperature (which is a LOT hotter than EGT - which is measured at the OUTLET - FYI)

So TOT is TIT?

 

[BallVice]

Ever driven a new car? The only gauges they have are speed, fuel and tach. These diesels also never came with pyrometers or boost gauges from the factory, and most have been on the road for 25 years with no issues.

If your engine is tuned to run properly and safely, no real need for extra gauges in my opinion.

If you are wanting to change aspects of how the engine runs, notice the changes, run it to its limit and want to look cool, then gauges are a must.

Thenissue on a tune is - it’s a point in time. As “density” altitude changes - so does the tune of the vehicleand the performance.

Mines a 1981 - not a new vehicle - and there’s a reason new vehicles have computers on them - mine does not.

What year TD are you driving?

 

[gerg]

Heh. No, I just tune it so that its darn near impossible to get the egts too high.

 

[fitzmooney]

TIT and EGT are the one and the same and measured at the turbine inlet.
CDT is measured at the compressor discharge, before the intercooler.
I have the advantage of a mixture adjustment in my Mooney M20T.

 

[Dork]

Thenissue on a tune is - it’s a point in time. As “density” altitude changes - so does the tune of the vehicleand the performance.

Mines a 1981 - not a new vehicle - and there’s a reason new vehicles have computers on them - mine does not.

What year TD are you driving?

I got a '95 with the hdft. I myself do have the gauges because I am wanting to push it a bit harder.

I just assume a proper safe tune, likely to factory specs, would be ok to drive anywhere without much cause for concern. If Toyota shipped all these trucks ready to grenade themselves if anyone held the gas down on any incline, they probably wouldn't be so well known for being reliable.

 

[CycloSteve]

Here is my real-life story of why both are helpful.

Last Saturday I was 700 miles into a 1,000 mile trip towing our enclosed trailer coming in at about 3,000 pounds...almost to the top of a long 6% grade I hear a "pop", and instantly lose power. Look at the boost gauge, and zero boost, look at the EGT and it is instantly rising from 900 degrees F towards 1200. Copious amounts of black smoke from the exhaust confirm that my 1HD-FT is now just a 1HD-F with all of the boost blowing out into the wind. Knowing that the motor "can" run without the turbo, I slow down and ease it into 2nd gear and crawl up the hill watching the EGT's. Safely get to a turnout at the top, instead of sitting in the traffic lane with semi trucks whizzing past at 60mph. Fairly quickly figure out which hose-clamp gave out, and get it back onto the pipe.

So, IMHO both helped to keep my motor alive, and get us to safety. Secondary issue is that I will now be replacing all of the crappy worm clamps on my Safari Intercooler with proper T-Clamps...I guess 25PSI is more than Safari was planning on with that design.

 

[Glenn-BJ74]

Cyclosteve - this says a good quality worm gear clamp has more consistent circumferential force than T-Bolt clamps -

Resources - AMS Performance
refer to RHS list " Why a worm gear clamp works better than T-bolt clamp"

I am using the Breeze liner clamps - which have an inner liner to protect the soft silicon.
Breeze - Breeze Liner - Breeze Hose Clamps

I have seen intercooler hoses blow off because of oily surfaces between the silicon hose and the stainless pipe.

 

[GooSe77]

I have a redarc boost / EGT / coolant temp gauge (all in the 1 gauge), and generally only look at this, my fuel gauge, and speedo. The boost gauge has picked up a boost line that popped off that I wouldn’t have otherwise noticed (apart from no green light), and when towing my boat in hot weather I pretty much drive to the egt and coolant temp....
In short - yes, they are worth it long-term...

Got a link for me to that gauge ?