Here is the scoop with the egt's on a a stock truck and a modded truck.
I decided to do a little test with my O4 baby before I went crazy with the mods so the very first thing that went on were a set of AutoMeter Ultralite guages. My probe is pre-turbo in the manifold right between 3 and 4. The temps recorded are as follows.
Conditions:
121*F - Death Valley
Clear
5mph wind (head wind)
6% incline (1. 87 miles long)
Truck Fully loaded with a Full toy box (9546lbs at the scales)
Bone Stock Truck in OD
63mph top speed up the hill
egt's = 1290*F
1750rpm
17. 5psi of Boost
Bone Stock Truck in 3rd
58mph
egt's = 1310*F
2700rpm (around there... I was a little pre-occupied with the egt guage!)
17. 5psi of Boost
Truck w/Mods OD(4"DP, Cool Air Intake/Pro Guard 7, Edge EZ, Boost Elbow)
65mph up the hill as a baseline comparative
egt's = 1100
2200rpm
30psi of Boost
Truck w/Mods OD(4"DP, Cool Air Intake/Pro Guard 7, Edge EZ, Boost Elbow)
75mph top speed up the hill
egt's = 1250
2200rpm
35psi of Boost
Truck w/Mods 3rd(4"DP, Cool Air Intake/Pro Guard 7, Edge EZ, Boost Elbow)
68mph
egt's = 1370*F
3000rpms
35psi of Boost
The only difference between the two days was the temps... . there was about a 5*F difference in the two days.
I dropped about 200* with the mods, but I don't think the egt's dropped due to the intake or exhaust, I think they dropped due to the amount of boost. With out the boost elbow (has a pin hole in it to trick the wastegate) the temps were rediculous.
The injection does change the egt's in an adverse way STARTING at 2700rpm. At that rpm, the injection system starts it's Multi-firing and adds fuel on top of what is actually needed. The injection system is thinking that it needs to deliver more fuel due to the rpms that are being produced. Call Diesel Dynamics, Edge whomever you choose and they will tell you the same thing.
I do believe that the exhaust and intake help to not hinder the mods and HP gains. Without the exhaust and intake, a choking effect would occur.
IN the old days, if we wanted to drop egt's, we would down shift and make more boost via more RPM's. I don't care what diesel truck you owned. Not the case in the world of common-rail systems... great for the CUMMINS owners due to the fact that we develope power much earlier. We are simply more productive before other trucks. Wait until you are pulling hard next to your buddy with about the same weight.....
I'm am completely embarrasing Duramax's with 125hp boxes, and leaving Ford's with their new 6. 0 PowerStrokes. I'm am a convert to Cummins but am now a true believer. I tow with a bunch of guys back and forth to the sand dunes about every other month. They hate me
Cheers!
