2LTE pyro readings (1 Viewer)

crushers

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so i finally got around to installing the pyro into the LJ78 i have been taking on the River Shiver pre-run runs and it is a good thing i did.
the LJ78 that has the stock exhaust was running a bit on the hot side hitting 1100F fairly easy when accelerating. the run last week i crunched the exhaust on the test run LJ78 and thought nothing of it but once the pyro was installed the damage was easily read in teh pyro. the temps run steady at 1000F on the highway even when not accelerating and when climbing the hills in the bush it read 1200F very quickly.
On tures the muffler arrives that i like to use so the new 2 1/2" exhaust will be installed on this truck and i will report back any change that i find with the higher flowing exhaust on the pyro...
i really feel that the high EGTs is the downfall of the 2LT and 2LTE heads...
cheers
 
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crushers said:
so i finally got around to installing the pyro into the LJ78 i have been taking on the River Shiver pre-run runs and it is a good thing i did.
the LJ78 that has the stock exhaust was running a bit on the hot side hitting 1100F fairly easy when accelerating. the run last week i crunched the exhaust on the test run LJ78 and thought nothing of it but once the pyro was installed the damage was easily read in teh pyro. the temps run steady at 1000F on the highway even when not accelerating and when climbing the hills in the bush it read 1200F very quickly.
On tures the muffler arrives that i like to use so the new 2 1/2" exhaust will be installed on this truck and i will report back any change that i find with the higher flowing exhaust on the pyro...
i really feel that the high EGTs is the downfall of the 2LT and 2LTE heads...
cheers
One of the things I am doing with my 13BT is one change, run a few tanks and check mileage/pyro temps, etc for changes, then do another change...etc. One of the last things I anticipate doing is a 2.5" exhaust. I anticipate lower temps as well, and better response overall.

Are you saying the Engineers at Toyota did not have to redesign the head...and all they needed to do was make a larger exhaust?

Allowing easier flow and getting rid of the exhaust gases certainly would help EGT's with any engine...and may assist those that appear to have design weakness's.

gb
 

crushers

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I ain't no engineer, and i definately do not pretend to be but if it makes the heads last longer then just maybe...

i want to try that, increased air induction and see what happens. i have a lift kit coming in from Jpan for the LJ78 and if i am going to larger tires then i want to take care of the heat dispersion first...
 
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If you talk to the Allhead people, they're convinced the heads crack because of cavitation produced by the stock water pump, as well as temp shock caused by steam trapped in the head. In fact, if you buy a head from them, it comes with a kit to allow the gasses to escape the head - they actually tap a fitting into the head and run a hose out of the head to vacate the steam.

But I guess the overall idea is to reduce stresses on the head, and there's no doubt that lower combustion temps equal lower stress.

Robin

[Edit: just as a comparison, my truck was running about 800F with factory exhaust on the highway between Calgary and Lethbridge at a steady 100 kph.]
 
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light_duty said:
But I guess the overall idea is to reduce stresses on the head, and there's no doubt that lower combustion temps equal lower stress. Robin
Yes, well said. It is one of a number of things that has been discussed before on this forum; reduce fuel, increase air, increase thermal transfer efficency of the coolant system, increase exhaust diameter...all seem ways to manage heat dispersion.

Waynes example reaffirms for me how appropriate it is to run a Pyro gauge. I did not for years, and thought nothing of it. How many exhausts have been "tweaked" and the impact not even realized till it was too late.

gb
 
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Greg_B said:
Yes, well said. It is one of a number of things that has been discussed before on this forum; reduce fuel, increase air, increase thermal transfer efficency of the coolant system, increase exhaust diameter...all seem ways to manage heat dispersion.

Waynes example reaffirms for me how appropriate it is to run a Pyro gauge. I did not for years, and thought nothing of it. How many exhausts have been "tweaked" and the impact not even realized till it was too late.

gb

Hey Greg,
What would be the best set up for exhaust? 3" pipe w/ a high flow muffler? And where can I find a pyro for the 1HZ-T?

Thanks,
Michael
 
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Greg_B said:
Yes, well said. It is one of a number of things that has been discussed before on this forum; reduce fuel, increase air, increase thermal transfer efficency of the coolant system, increase exhaust diameter...all seem ways to manage heat dispersion.

Waynes example reaffirms for me how appropriate it is to run a Pyro gauge. I did not for years, and thought nothing of it. How many exhausts have been "tweaked" and the impact not even realized till it was too late.

gb
I think actually the more important thing is to reduce the temp difference between the inlet and exhuast side whihc I think is more to do with the cracking than the actual overall temp. As Wayne's Pyro figures show the EGT is very high and this would get through the exhaust manifold and Turbo to the head on the exhaust side. The Burn Temp is actually much higher than those pyro temps show - you need to reach 2500 degrees F before you get Nitogen Oxides formed and that is the temp that the EGR tries to keep the burn below. Not6 sure what the actual head temp gets to but it would be interesting to see the difference in temp between inlet and outlet.

Reduction in EGT is just one of the benefits of installing the larger exhaust - especially with a 3 inch dump pipe. It helps clear out the high temp exhaust gases better, it reduces temp at the turbo and also reduces turbo lag by allowing it to spin up faster. (spin up is directly related to the difference in the inlet pipe size and the outlet pipe size).
 
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guenther65,
I am running a 2.5" on my 3B-T. Even before the turbo was installed, it made a difference in EGT's and power.

As for a pyrometer for a 1HZ, any decent autoparts store or speed/performance shop will sell them. They are about $125-$175 Cdn (not sure where you are). Since you drill your own hole for the pyro in the exhaust (or manifold if you prefer), it is a generic fitting which will fit any engine.

Craig.
 
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lumpy70 said:
guenther65,
I am running a 2.5" on my 3B-T. Even before the turbo was installed, it made a difference in EGT's and power.

As for a pyrometer for a 1HZ, any decent autoparts store or speed/performance shop will sell them. They are about $125-$175 Cdn (not sure where you are). Since you drill your own hole for the pyro in the exhaust (or manifold if you prefer), it is a generic fitting which will fit any engine.

Craig.
guenther65...what he said...and seems 3" is the point to look to now.

Both Stone and Sheldon have gotten the EV series from ISSPRO. I've got the Autometer. EV seems the easiest to read, if you can not mount the gauge face right to the driver.

Check out this thead: https://forum.ih8mud.com/showthread.php?t=35053

Now back to regular thread programing...

hth's

gb
 

crushers

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harveya said:
Reduction in EGT is just one of the benefits of installing the larger exhaust - especially with a 3 inch dump pipe. It helps clear out the high temp exhaust gases better, it reduces temp at the turbo and also reduces turbo lag by allowing it to spin up faster. (spin up is directly related to the difference in the inlet pipe size and the outlet pipe size).
Harvey,
so the truck is down at the local exhaust guru. he is putting 3" flex dump and mandrel bends from the flange to the next flange then dropping to 2 1/2" from there back to the tail. the exhaust will be routed to ust behind the rear tire so it does not get crunched again or plugged with mud or snow etc.
i hope to get it back in a day or so... man those mandrel bends are not cheap or is the 3" braided flex...
OUCH!!
i will let you know what i find as a result.
cheers
 
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crushers said:
Harvey,
so the truck is down at the local exhaust guru. he is putting 3" flex dump and mandrel bends from the flange to the next flange then dropping to 2 1/2" from there back to the tail. the exhaust will be routed to ust behind the rear tire so it does not get crunched again or plugged with mud or snow etc.
i hope to get it back in a day or so... man those mandrel bends are not cheap or is the 3" braided flex...
OUCH!!
i will let you know what i find as a result.
cheers
How large is the dump out the turbo?

13BT dumps straight down, to miss the booster/brake/clutch stuff. I've looked at the 12HT/1HD-T turbo dumps, and they look like they would angle it to the frame instead of straight down, so I was simply going to use the stock dump from the turbo, and go wider from as close to the flange as possible. Is that what he is going to do for you?

gb
 
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crushers

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the dump itself is only 2" so we are setting to increase from that to 3" flex with in a couple inches then the mandrel over the frame and another 2 bends heading to the conector...
cheers
 

brownbear

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crushers said:
the dump itself is only 2" so we are setting to increase from that to 3" flex with in a couple inches then the mandrel over the frame and another 2 bends heading to the conector...
cheers
2-3 is a big jump up. When I was at the exhaust shop making up my turbo intake, I was doing something like that. It took a few pieces. Could not do it in a single pipe.

I will bet you have to do it in three pieces total. So thats the one coming down, then a mid piece(for a step up,) then on to the 3"

When they try to stretch to the max it sures pops when it breaks...........
 

crushers

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so here is how we ran the exhaust. the first section of 3" was a real PITA but Greg succeeded in making it work...
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crushers

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and out the back.
i really love the exhaust exiting half way on the tire and out the side. it prevents mud or water or snow etc getting pushed into the tip and the tire rotation / air flow from the wheel keeps the exhaust flowing out the back. this is really good for trucks with the tops off since you do not end up with the gasses being circulated back into the cab area...
hopefully tomorrow i will be able to test the system for EGT reduction and to see if any performace gain was achieved.
the cost of this system is double the normal 2 1/2" system.

the system is extremely quiet which is one of the goals i wanted to achieve...
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brownbear

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This is a 3' exhaust on a 2.4? looks nice. I was interested how he started the pipe. '

Definately will not be a hold up for exhaust temp.

What did he paint it with? I used to use a spray stainless steel, called 1200S. Was awesome. did not chip or peel. Used it extensively on steel parts used in the ocean.

Was good to 1200 degrees I guess?? That spray kinda of looks like it.

Congrates.
 

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