Primary compressor discharge temp oscillation

Joesixpack

Joesixpack

Pull'n it.
Joined
Apr 4, 2008
Messages
4,118
Dynoprimaryairtemp.jpg


Blue primary air temp, Black secondary in F

Thought it was interesting, can't hear it or see it in the pressure gauge yet the fast exposed element thermocouple catches it.

Should be some interesting stuff when the rest of the instrumentation is installed.
 
What's up with the 25* temp drops from the primary.

Garrett

Probably getting paid at work to post this from my D1
 
Pressure wave between the compressors? Primary crawling up the surge line.....not even sure.

That 400 degree air from the primary has to be making some serious workload for the secondary however.
 
Old one, going to pull as much data off of it as I can before the switch.
 
WOW!! Very cool thanks for sharing. Do you mind telling us what the twin setup is and boost psi?

I can only think of surge, or maybe try running with the filter off.
 
i wish i was smart enough to interpret this information, i bet id learn something.
 
That looks way too repeatable and uniform to be from the turbo IMO. Sure its not a thermocouple issue? Have you tried reversing the thermocouples to see if the readings change or stay the same?

Sent from my Droid using Tapatalk
 
what really confuses me is that the secondary gets its air from the primary, how could the primary fluctuate and not affect the secondary at all? If it were me i would do what gr8shot said and switch the primary and secondary sensors around and see if I got the same results. On a side note what pressure ratio are you running on the secondary? I am suprised it only heats the air an additional 100 degrees.
 
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The first time I seen that I did change to another channel and different thermocouple, still seen the same thing, didn`t start logging temp till the last few so when its back up on there I`ll look into it more.


Here`s another,
The high black line is with the secondary gate set locked down for maximum PR through it.

Low black line secondary locked wide open. Not only outlet temp was much lower, HP on top was up as well. (Not surprising)

Primaryvssecondary-1.jpg
 
....tried clicking the 'x' in the upper right corner of the pic to close it... AHAHHA
 
Oooof, had to google that one...but its all superflow so I`m leaning towards they are. I know there was a spiel in the manual that suggested it was a good idea to use their $200 a piece thermocouples..... :kick: Its silly repeatable anyhow.
 
How about a wastegate causing over/under speeding? Plot it against boost?
 
Joesixpack said:
The first time I seen that I did change to another channel and different thermocouple, still seen the same thing, didn`t start logging temp till the last few so when its back up on there I`ll look into it more.


Here`s another,
The high black line is with the secondary gate set locked down for maximum PR through it.

Low black line secondary locked wide open. Not only outlet temp was much lower, HP on top was up as well. (Not surprising)

Primaryvssecondary-1.jpg
Click to expand...



What is the maximum pressure ratio on the secondary locked down vs secondary locked wide open runs?

Also, at what pressure ratio, and RPM did the peak power from the locked shut run cross over the locked open run?

I'm trying to get a feel for what discharge temp and pressure ratio equates to maximum HP on your setup.
 
Big Blue24 said:
What is the maximum pressure ratio on the secondary locked down vs secondary locked wide open runs?

Also, at what pressure ratio, and RPM did the peak power from the locked shut run cross over the locked open run?

I'm trying to get a feel for what discharge temp and pressure ratio equates to maximum HP on your setup.
Click to expand...


Good show, thats exactly what I was looking for.

The spikes are from the optical rpm sensor. Going to tie into the cam sensor as its proven to be tricky to get a good signal from that optic sensor.

This is with a set of bone stock injectors, smarty. 64/71/13 480

So with relatively low fueling the crossover looks to be in the 2700-2900 rpm range. Keeping the gate as tight as a nuns **** up till there is all good....(stock injectors)

I'll make the same pulls again with the stand alone and fuel the piss out of it and see what it looks like.

I'm waiting on the other panels to log pressures so when they arrive I'll make the same pulls as above logging everything.

So just off the hip I think manifold was around 75 and 29ish of the primary gate locked down.

Locked open manifold 65ish and primary hardly different, maybe 30.

Frankly it seems silly to think my ported out internal gate would ever flow enough at 4500+!!!!! Still don't know how that top charger was hacking it.

crossover.jpg
 
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