Where Do EGTs Turn Into $$$
 

Just got my EGT, Boost, and Trans temp gauges in last weekend. My question is, with my pyro situated between cylinders 3 and 4 what does everyone think my safe EGT limit should be? I'm seeing some 1000 to 1200s right now during short WOT bursts, 600-900 normal around town and highway driving??

What is a safe trans temperature?

Thanks.

Same as I'm seeing stock. 1350 and under for an extended period. :tu:

Ive always thought it was 1250F sustained.

The melting point of aluminum is 1250F. You also have account for measuring error. Id rather err on the side of caution when it comes to a piston meltdown.

What are everyones thoughts on the trans temperature? I am using a genos garage acu temp adapter that wraps around the trans line so I'm looking for a baseline. It's running around 130-140 around town, and 120-130 open highway??

Cummins claims they tested the +04.5 trucks at 1450 degrees EGT's and they are rated to run there. Keep it at or under 1300 sustained and you should be good. FYI, that is with stock timing. Once you modify the timing all bets are off.

Trans temps in the hot line generally run 160-180, on mine at least. As low as 140 when it gets really cold. Operating temp is 140-230 degrees, if your in that range its good.

The Accu-Temp is not so Accu from what I have seen. Most seem to run 20-30 percent cooler than actual from posted temps.

On days like today, my trans temps never went over 110, and the sensor is in the pan.

different motor, but dmax are rated for 1350 sustained. they do have aluminum heads, but it dissapates heat very well.

i have burried my pyro on many occasions ive considered getting a 2000* one before cause ive kept it hammerd for a while.

id be more concerned about the wheter the turbo can take it or not not the block.

Thanks for all the good information. Does anyone know what the timing advance on the different smarty levels are? I'm not running anything stacked on the smarty, but I also only run level three due to my stocker tranny. Anyone know.

well bassically adding timing will lower egt's and increase fuel economy. theres alot of playing around though to get it the way you want.

Jeez, thats not even av alid comparison considering the day and where you are. "Days like today" indeed!! :D

I think this is the non-TNT version but it has slipped my mind.

#1 12*

#4 16*

#3 18*

#2 21*

Does everyone else run the added timing or should I be running the programming without timing?

You had BETTER be concerned if your pistons will take it, forget the turbo. Its gonna toss one soon at those temps. :scare2:


Be CAREFUL with advanced timing and lots of fuel on the +04.5 trucks, the 3rd event and piston design causes some issues when you push the envelope.

Its not all about EGT's when you throw timing in the equation. It quite possible to melt a piston at under 1300 degrees with the right conditions. You have to be aware of the cylinder pressures and temp create by the timing and duration of the tune or it will not be a good day.

I guess I forgot to mention I'm not trying to run what everyone else is running, but is the added timing safe considering my mild mods?

the trans temp should run 40 degress lower than your coolant temp

Depends on where you measure it at. Measured in the pan 20-30 degrees less, in the cooler return line 30-40 degrees less, in the hot line with the TC locked 10 degrees less, unlocked TC anywhere from 180-220. There is no hard figure for how much the temp should vary from coolant.

The only range that makes sense is 140-230 degrees because of the variations in use.

If your pryo prob is in front of the turbo (mounted in your manifold not in the downpipe behind the turbo and if it is mounted in the down pipe your gauge will read anywhere from 200-300 degrees cooler than what your actual temperature is) then once you reach 1600 F and beyond on your gauge then you are causing engine damage and thus engine damage = $$$$ i hope this info helps!!

Everything I have seen for cummins motors says 1250 and below is ok, anything above that might be playing with fire (so to speak)
Scott

I was always told 1250 was the limit and to back out at 1100 just to be safe. I say why take a change running higher numbers being you never know if your gauge is 100% accurate at any given time, leave some room for gauge error.

The 1250 number is a safe range all the way back to the 12V's, You can run the 12V's up to 1500 for several minutes at a time without issues.

The CR engines run a lot hotter for emissions reasons and have the parts to handle it. Better valves, valve seats, exhaust manifolds, better piston cooling handle higher temps easily. The 600 series motors were tested by Cummins stock at 1400-1500 degrees and Cummins says it is fine, the earlier engines will run 1300-1400.

Is this before the turbo (between #5 & #6 cyl in the exhaust manifold - between the head and the turbo) or after the turbo (in the downpipe - between the turbo and exhaust). Just trying to clear up the details for everybody who is just getting into these... Like me! :tttt:

Every EGT temp I ever talk about will be pre-turbo. Post turbo, the discrpency is so great its not reliable if you are pushing performance. With a small housing and lots of fuel +500 degrees difference between pre and post turbo is not unusual. Its better with stock fueling but who has that anymore? :w2:


For the most part you will see 100 degrees or less difference across all the cylinders. MAYBE 50 degrees hotter as an average on the back cylinders. Most of us run the probe on the back 3 to get the highest temps.

Just remember what we are looking at for EGT's gets dramtically effected by timing. The reason why the newer trucks see so much more temp is the timing is way retarded and a lot of the heat is being ejected from cylinders before they have a chance to heat soak.

A 12V or 24V will have timing already advanced and thats where the 1250 all day is really applicable. This range is for 12/24V but is still apllicable IF you are running advanced timing:

Up to 1250 - constant duty

1300 to 1500 - 3 minutes out of 5

1500-1800 - 1 minute out of 5

1800 plus - 30 seconds to Chernobyl


Retard the timing to the range of the stock CR setting and you should be able to add 100 degrees, 150 if you feel lucky, to alll the numbers and be relatively safe.

You really have to understand your power adding boxes and changes when it comes to gauging the impact. Been more than few running 1200 degrees constant with advanced timing have melted pistons due to heat soaking the cylinders. The 600 series engines are even a little trickier as the pilot event is extended and the main event either extends under load or the ECU adds a 3rd event. (Thats another whole discussion the jury is still out on)

Hope this helps clear the smoke a little. :tu:

That is what I figured, but now I know for sure! Thank you so much.:c: