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Very high egts towing..

Bill Heath is away for a week or so...:suicide:
I'm gonna try cutting the TM back a little. I "think" the truck has 3.73's IIRC. Plus I am running 235's not the stock 225's. It is a much taller tire. In fact the truck goes 5 mph faster than the speedo reads. when the speedo reads 60, I'm going 65 at around 2100 rpms.
 
I'm not rolling serious coal under heavy throttle but a darkgrey/black haze. Not bad at all. Truck runs very smooth and starts better than any I have owned thus far. It is amazing how bad the turbo beats the sh$t out of the motor. My Burb has a pyro and I could not get that 6.2NA over 600 if I poured gas down the intake...:D
 
I do not really think it is the boost causing your issue Kenny. It sure is part of it. the other part is timing on the reflash. You can get higher EGTs from either too advanced or too retarded. The stock tune is kind of retarded during max fueling, which hurts your power, but keeps the engine cool (relatively to too advanced). I would venture to say your timing is too advanced now. If you had the scanner you could see what it is. With no load, high timing is no problem, but for towing the timing needs to plateu or actually come down a notch at what would be sustained fuel rates, so around 40-60mm3 (near the stock max fuel rate) you might want timing of about 13-14 degrees of advance, which is cam timing, in actuallity that is 26-28 degrees at the crank. Thats assuming youre around 2400rpm. Timing can be higher at lower fuel rates and higher at higher fuel rates when you really just want more power, but in that window where you just want to maintain a pull for a while the timing needs to come down a bit. I run timing up to 23 degrees which is 46 at the crank, but only at high rpm, and high fuel rate.

You can also easily fix your speedo by modifying the VSSB. I put dip switches on them so you can adjust at any time. I have an extra if youre interested, that can effect tranny shifts, tranny pressure, and TCC lockup, as well the odometer will also be off.
 
Acesneights1 said:
I'm not rolling serious coal under heavy throttle but a darkgrey/black haze. Not bad at all. Truck runs very smooth and starts better than any I have owned thus far. It is amazing how bad the turbo beats the sh$t out of the motor. My Burb has a pyro and I could not get that 6.2NA over 600 if I poured gas down the intake...:D
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I'm not so sure that's the turbo, more of a fuel program mapping.

My 6.5 would jump right up in EGT's with not much throttle or load when the turbo control went out.

Once I figured out that my boost sensor and wastegate solenoid were crapped out, the EGT's came down to where you would expect.

I would assume the 6.2 is "scheduled" properly to run the way it does.......
 
This is interesting as to the smoke on my 6.2 re power. EGT's were in the not possible range per Heath. Still suspect the gauge as the engine didn't melt down.
 
My EGT gauge barely moves on regular programming, but I can positively make it go up if I do something a little too radical with the advance and fueling, and if I didnt have the right amount of boost it was even worse. I run higher boost with the GMX and even with the ATT I will go higher than 15psi. So I originally thought my EGT gauge is bad because it reads too low, and climbs slow compared to what some people say, but then I proved I could make it read high and climb faster.
 
Recall on the other site prewar days when there was a fair amount of activity with tm,s that increasing boost a certain amount was shown to actually lower temps ,inlet air & exhaust ,but going higher ,15 psi or so? temps went up due to restricted turbo or whatever . I dont think retuning was involved tho. Backing off the spring seems to be a good thing to try .
 
Diesel -T said:
Recall on the other site prewar days when there was a fair amount of activity with tm,s that increasing boost a certain amount was shown to actually lower temps ,inlet air & exhaust ,but going higher ,15 psi or so? temps went up due to restricted turbo or whatever . I dont think retuning was involved tho. Backing off the spring seems to be a good thing to try .
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This is exactally what I noticed. I had been running the factory vac sytem on my 96' for quite a few years before i went the TM route. Now keep in mind this truck is a 5spd manual...but I tow anywhere from 5k to about 10K with the factory programing as well. I cant tell you how many times with the vac system i would have to back off the throttle under load to lower the egt's. I could climb to 1200* on hills with no effort at all.

After I installed the TM I set it to max out at only about 11psi. I really dont like pushing the boost much past that on any of my 6.5's. I found that after the TM install (and the updated round filter airbox soon after) my egt's very very rarely ever come close to 1200. In fact, at this point in time 1000-1100 is when I back off.

Now after driving the same roads, towing the same weight I was towing before, i can say without a doubt that the TM lowered my egts. Granted I dont do alot of highway towing so that may also hold a different story, but the few times I have, I havent run into any issues.

My advice to you kenny would be to back off the boost numbers and see if it makes a difference or not.....otherwise I would suspect a programing change
 
Acesneights1 said:
Hard to say. Vac pump may have not been working since i bought the truck and I installed gauges to verify boost issue. I guess what I am sayiong is I have no data towing pre TM and Reflash but truck did not run hot AT ALL and I towed in 100 deg heat. Last trip was mid 70s and it hit 210 many times.
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If your vac system was out, the engine would be a dog and it would blow heavy black smoke continuously. Been there and done that.
 
There's a point of diminishing returns, with boost... one that you have to play with a bit to find, given your specific gearing, the weight you pull, whether or not you have an IC, all that stuff.

Adding boost will LOWER your EGTs, up to that point. After that point, the increased IATs and the tight eastegate mean the more you push on things, the hotter it gets.

Like I said, I just backed off and took what the truck gave me. Most of the time, I didn't need to, but then, I had a towing tune, 3.73s, and standard injectors. If you have a GL4 and Marine injectors (and likely 4.10s, given you're in a 3500 dually), you'll have a different set of parameters to consider.

I'd take it back 1/4" to start (or tighten it up, one or the other) to see what happens. Then hook on the trailer, drive and adjust until it does what you want.
 
ATT Kenny, you knew that was coming at some point :D , programming from when you 1st got your flash vs. what Bill has now probably a big part, and yes increased back pressure with hogged down TM isn't helping any, for the IC check with Terry aka TMHark, he just retired his WTA setup & is looking for a buyer I think.
 
Truck is drivable, Just have to really watch gauges and drive by them.

Problem is climbing a grade you got that slowpoke in the right lane and the truck CAN easily pass him but I'll be at 1300+ egts by the time I do but if I put the system back to stock it wouldn't pass slow pokey anyway cause it wouldn't have the power.

Bottom line I don't really think an IC is going to help.

I think the waste-gate is building too much back pressure vs the substantial increase in fuel so basically it has to be driven with care. That is why GM had the system the way it was because most people wouldn't know that and melt the motor.

The egts are directly relative to position of right foot...:D By playing with which gear and how much fuel I give it it can climb a hill very nicely Just have to play every grade by ear and see how the ECTS, EGTS and Boost are and find it's happy spot.

I really don't think there is a way to make this truck to the point where you could just get in it towing that kind of weight and just mash the pedal up a long grade with no worries.

It's either leave it stock and a dog or turn the bitch up and watch every gauge. This stuff is nothing new.

Plenty of guys have turned up the pumps on class 8's(Cat, Mack Cummins) and have to drive em by the pyro.

I got a 3208T(very similar engine to the 6.5) and I got the fuel cranked up in that one and i can't stay in it very long without fears of a melt down.
 
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EGTs are directly related to IATs and timing has a big factor in there. inject too early and you are fighting against the momentum of the pistons and not even getting great combustion and firing before max torque can be achieved ATDC, which just puts more heat into the cylinder raising ECTs, and waste fuel out the exhaust. And here comes the worst part, because youre working against the momentum and losing power, you ask for more fuel to get more power that further works against you, and temps go crazy
 
As a FYI Thursday on the return trip home to Ms with the new program, I briefly ran 103 mph gathering some data with 98F OAT, no IC, no WMI, 11 psi boost, IAT 273F, 103 mph, EGT 1050F, 61.4 mm fuel, 3130 engine rpm, 199F H2O.

IMO while IAT can be a contributor to high EGT; fuel/timing is more important than IAT.
 
I agree with that, suppose you dropped IATs 100F then your EGTs would probably be 100F lower. But put more fuel in with improper timing and cylinder and heads will absorb more heat and EGTs will go up several hundred degrees.
 
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