Competition lower EGT = better performance?

[Forrest Nearing]

just wondering if there was a direct relationship between EGT's and performance...



I've noticed that when rolling into a 3rd gear punch with the EGT's already getting up there, the truck doesn't seem to pull as hard as going from a dead stop 2nd into 3rd... like if I'm pulling away from a light and the EGT's are 300ish, going from 2nd into 3rd, the truck pulls harder in 3rd then than if I were cruising along in 3rd w/ the EGT's 600-800ish and nailing it.



but, the EGT's get well above that in 2nd before I hit 3rd...



intercooler heat-soak perhaps?



Forrest

 

[Turbo Tim 1]

I am thinking that by your description it has more to do with the power band of the engine, ie torque curve.



#ad




By looking at this graph (if it works) you can see the torque doesn't hit hard until 1600 rpm or so. Can you correlate your assumptions based on engine rpm?

 

[Forrest Nearing]

same RPM in 3rd gear... only variable is hitting the throttle from a roll vs. rowing through the gears from a dead stop.



Forrest

 

[Bob V]

I had a similar experience with my truck. I found that I was over-boosting, getting out of the efficacy range of the turbo and loosing power. Try letting of the throttle a little and see if you get a power serge. If you are over 35 pound with a stock 35 this my be the problem.

Bob V

 

[Forrest Nearing]

hmm... interesting... I've got it set at 35lbs, but sometimes it'll go 37-38... maybe that's what was happening.



Forrest

 

[1dslram]

The HX35 is good to 35# and still in it's map, over that and the air will heat very fast. Rember for every 1* the intake temp. goes up the exhaust temp. goes up 1. 4*.



The major cause of high EGT's is over fueling. If you have EGT problems you need more air = a larger turbo or twins. I went with the larger single first and then went to the twins and am ready for more fuel now that EGT temps are in check. It will never end. Methanol injection is in the works also, soon to be installed.



The goal was over 600 before 1/1/04. I am but won't make it to the dyno until after 1/1 the flue took care of that.

Bruce

 

[Forrest Nearing]

well, that's why I've got it set at 35lbs... once into boost pretty good, it doesn't blow black smoke or anything... a slight haze maybe, but nothing crazy. EGT's are managable, but yes, I'm saving for another turbo so that I can slide that plate forward some!



Forrest

 

[Bob V]

You might find this interesting.

http://www.gnttype.org/techarea/turbo/turboflow.html