EGT's with Heath P-Series Chip

[Chief915]

Not sure I have a problem here, just looking for your thoughts/opinions. I bought a Heath P-series chip a few days ago and installed it, everything is great with the chip. Got around to installing my EGT gauge tonight and went for a ride. I mounted the thermocouple in the exhaust elbow of my GM-8 turbo by the way.

First impressions are that the gauge must not be working quite right. I flogged the suburban full throttle, not towing anything, 6 or 7 times from 0-60 and 30 - 70 and about 450* - 475* F was all I could get on the EGT gauge. 13 - 15 psi boost, great power, etc. As soon as I let off the pedal, the temps drop to 300-325ish within 5 seconds or so.

I had read other peoples posts about the P-series chip, how "hot" of a tune it was, and that you could easily run into EGT problems when towing. I guess maybe I just built it up in my mind to expect to see higher temps while I was beating on the truck. I realize towing, or more load on the engine, will increase EGT's.... But I figure if I really have to work at it to get to 450* - 475* while it's empty, towing shouldn't be too much of a problem either.

Does these temps seem fairly normal or is my new gauge suspect? I am happy to see low EGT's, but at the same time I am curious of how accurate they are..... I tried to call Bill to see if these temps are to be expected, but they were already closed for the day.

 

[tanman_2006]

IIRC the exhaust elbow is cooler than pre turbo. Preturbo is where the 1100* is seen. IDK if that is what you were thinking you would see.

 

[Chief915]

IIRC the exhaust elbow is cooler than pre turbo. Preturbo is where the 1100* is seen. IDK if that is what you were thinking you would see.

Yea, I am tracking it will be a different temp pre vs post turbo.

I wasn't expecting to "max out" on EGT's...... More or less I was just under the impression, from reading other's posts, that the "max performance" tune that I got would have higher EGT's than what I am seeing so far. I know they will go up when towing, that's common sense, I just figured I would see more than 450ish when I was beating on it empty.

This is the post that had me expecting higher temps..... Maybe I was had it built up in my mind to be worse, temp wise, than it actually is.

I ran the Max e tork on my old OBD1 Tahoe. Truck ran like a bat out of hell but the egts were through the roof. Same with my Dually. Make sure Bill understands what you want. He tuned my Dually hotter than I wanted it. Thing would burn the tires but I could also melt the pistons real fast towing.

 

[chefmike]

I have my thermocouple on the little square that people talk about pre-turbo. I see 700 getting on the throttle empty. It will hit 7 to800 climbing grades at 2200 rpm. Getting off the throttle takes it back down to 450 or so, which is where it sits cruising.

not with heath's chip. sorry if you were asking specific to that. but mine has been chipped. I saw about the same before chipping. Maybe a little less.

 

[Paveltolz]

Be sure to call them on Monday morning. Your temps will be a little warmer with the ATT. How fast and how much boost while flogging it? My thermocoupler is in the Down Pipe and yesterday at 2000' I saw 15psi accelerating on boosted launch to 85mph with EGTs up to 1000 in no time. That's empty or about 6000lbs with driver luggage, guns and ammo.

 

[buddy]

I suspect the gauge is inaccurate. that or you are putting water in the cylinders that is cooling down the combustion, but you would probably notice that.

When I had the gauge post turbo I could still get 800F EGT temps easy going up a long hill at high throttle on a stock chip.

 

[great white]

Post turbo has been reported to be 100-200 degrees less than pre turbo. Sometimes more.

So, working on that assumption, your 300 or so cruising is pretty close to the 500-600 or so I get pre turbo cruising (around 100 kph) when empty.

You 450-ish is lower than my 800-900-ish flogging it (empty) though.

For reference, I'm running a Heath pcm (biased towards daily driver/towing vice performance) and TM on a GM8. My TM is adjusted to kill boost at 12 psi. So the extra air mass you're moving could account for the lower egt's.

Your temps seem pretty close to what I would consider normal for your setup. Maybe just a touch on the low side when hot footing it, although that's a good thing.

It's kind of hard to say comparing a post turbo thermocouple to a pre turbo. Almost and apples to oranges comparison. You just never know how much of the temp the turbine will eat up dependent on load....