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Are these numbers out of line?

T

thedrip

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I did a couple passes with gmtdscan running today, and I want to see if the numbers make sense. They seem alright to me (although the air temp is bonkers high). The truck is a 95 3500 dually, automatic, 4.10s, F code engine. As far as mods, I have the wastegate held shut with full vacuum, minus a pinhole I added. It opens up at about 9-10psi, depending on the gear. I also have a 10kOhm resistor in the signal line from the MAP (aka boost fooler).

So heres the numbers I see

MAP shows 12.4psi at idle, which makes sense. 14.7 atmosphere, - 2.3psi or so for the boost fooler.

Calculated boost is always 1.5-2psi lower than actual boost. I'm guessing this means the ecm could be fueling more? Related to the boost fooler maybe?

IATs are bonkers. 130F driving around (its 90F outside), gets upto 260 at WOT after 5-6 seconds.

Coolant temp stays at 198-199, gets upto 205 under WOT, but drops back to 200 still at WOT. Seems like its cycling correctly, just 5-10 degrees too hot. Gauge shows 210 steady the entire time =(

I just wanted to know if these numbers are WAAAAY out there. My next issue to sort out is a boost actuator code on the highway. My truck runs 7psi at 70mph. A little too much, and it ends up setting the check engine light and defueling. On-the-fly restart fixes it for a couple minutes. I will take my laptop along next time i happen to be anywhere near an interstate.
 
IAT looks to be in line with a non IC'd turbo engine. Don't forget air gets hotter as it compresses..

Makes you wanna mount up a charge air cooler, doesn't it?
 
Makes me want to finish putting together the water injection I started years ago for another truck!
 
Welcome to TTS!
If you have modded the wastegate to be sucked shut all the time - this is an inventive Turbo master setup. However, it isn't working like the computer expects. You need a tune or set the vac system back to stock and get a tune that will control the boost better.

Numbers look normal till where the computer can't control boost like it expects to. Boost fooler may not be helping.

Run the turbo to 14 PSI of boost and see what the IAT's do then. Hint: keep wire harnesses and other things away from the intake!

There are larger and better turbo's out there for the 6.5 when you get sick of playing with the restrictive factory POS turbo. Trade some of the low end for pull HARD past redline for one turbo kit. And see IAT's at 14 PSI like you are seeing at 10 PSI now.
 
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