Dash Daq boost readings

BFT · Aug 22, 2011

Dzchey21 said:
Didnt you already check with your mechanical gauge?

only used the gauge on the big charger

bigrpowr said:
no, i used the dynojet sensor, it read a peak of 60.1 , 58.8, and 57.9 ... on 3 different pulls. matched the dd to a tee. i think maybe tomorrow me and beefy will hook up the gauge to see. the gauge is only 60 psi ..but that should do just fine.

word

Dzchey21 · Aug 22, 2011

Klutch said:
I've seen 67psi on xstreet not really a wide open throttle run tho, I'm still using stock trans/converter at the moment. No time to install suncoast or go racing. Project is pretty much on hold.

67psi according to what the dashdaq?

is that 67 absolute or guage pressure, thats more boost than almost anyone is seeing from any truck... if its absolute that puts boost at 52psi roughly, which i buy

Whats robs truck see for boost

Craig@MPD said:
Mines dead on accurate with my edge cts

Whats the max boost you have seen from the set up? Is this verifiying with a mechanical gauge of some sort?

Dzchey21 · Aug 22, 2011

08stroker250 said:
The reason I brought Shone's truck up is because Cole says his DD and AMS read the same number. Doesn't sound like every truck is having the issue. I need to do a mechanical gauge as well to see.

Im sure tuning can play a factor in that, because im betting the tuner can rescale that table to fully utilize the input from the map sensor. on more than one set up i have seen the boost number stop but the voltage still increase from the sensor return.

Craig@MFI · Aug 23, 2011

Dzchey21 said:
67psi according to what the dashdaq?

is that 67 absolute or guage pressure, thats more boost than almost anyone is seeing from any truck... if its absolute that puts boost at 52psi roughly, which i buy

Whats robs truck see for boost

Whats the max boost you have seen from the set up? Is this verifiying with a mechanical gauge of some sort?

52 psi at the end of the track just got Erics newest tunes today and it has alot more fuel so I'll see what it is tmw
I'm reading mine with my edge e.a.s system with 100 psi pressure sensor and then the factory sensor with the edge also and they are both accurate

bigrpowr · Aug 23, 2011

Craig@MPD said:
52 psi at the end of the track just got Erics newest tunes today and it has alot more fuel so I'll see what it is tmw
I'm reading mine with my edge e.a.s system with 100 psi pressure sensor and then the factory sensor with the edge also and they are both accurate

yeah, i doubt edge has the issues the dd does, i remember my boost being a bit higher on the lw as well. how is the driveability on the new race tune? is it really fueled up past half throttle ?

Jeff@Spartan · Aug 23, 2011

If the DashDAQ is the only one having issues, why does Cole's read correctly?

bigrpowr · Aug 23, 2011

08stroker250 said:
If the DashDAQ is the only one having issues, why does Cole's read correctly?

he doesnt know it reads correctly. its just a signal processor issue, obviously, dont take it personally.next time eric sends me another livewire ill compare them as well, just to see.

tensixniner · Aug 23, 2011

Has anyone tested to see how linear the output of the sensor is across it's operating range?
50+ PSI is probably outside the range Ford was working with.

Also, mechanical gauges are usually most accurate across the middle 50% of their scale. There are exceptions, but you might want to look up the specs of the gauge your using.

Jeff@Spartan · Aug 23, 2011

bigrpowr said:
he doesnt know it reads correctly. its just a signal processor issue, obviously, dont take it personally.next time eric sends me another livewire ill compare them as well, just to see.

Not taking anything personally. The DashDAQ reads from the Ford sensor, and as far as I know it reads correctly. If there is an issue, it needs to be addressed with Matt....and then with DrewTech. In the meantime, I am going to attempt to get a hold of a mechanical gauge to test this.

Dzchey21 · Aug 23, 2011

Its not just a dashdaq thing. Mike was running into the same problems data logging with ids... ibwould say its something more in the tuning than anything. Also maybe newer trucks don't have the same issues.mine is an 08 Cole what year is your drag truck

Klutch · Aug 23, 2011

Mine is a 10. I'll try and take it out today and confirm, haven't drove it fow awhile, just going off memory.

mike@haller's · Aug 23, 2011

I was having issues while tuning the gate and data logging with the IDS software. The numbers never matched the mechanical gauges that were installed. My thoughts were the pcm was not designed with 60 psi in mind and probably isn't scaled right in the tables for those boost levels. I could be wrong though. But this is also why dustin came up with his boost harness. Which uses the factory map sensor directly to the dash daq. And it's readings now match the mechanical gauges exactly.

Klutch · Aug 23, 2011

Checked the dd with key on. It's set at mgp which reads 0 and ebp reads 13.8, I'm at 2000ft

mike@haller's · Aug 23, 2011

Klutch said:
Checked the dd with key on. It's set at mgp which reads 0 and ebp reads 13.8, I'm at 2000ft

The issue only seems to be when the truck is at high boost levels. Everything 40 psi or below seems to match pretty close.

cowboy_dan · Aug 23, 2011

Will the 6.4 give some sort of an overboost code at some point?

What I'm thinking of is something I've seen at work:
-The controller measures the voltage from the sensor, and converts the voltage to a hexadecimal representation of the voltage. The controller uses this hex value for all the calculations and computations.
-The controller converts the raw hex value to a different format for transmission to another device, and somewhere in the conversion the represented value is skewed.

If you know at what pressure the CEL is supposed to come on and an overboost code be set, you can check pressurize the system slowly and see what pressure (via mechanical gauge) the code come up at.
If it is supposed to come up at 62PSI and it does, but the Dash daq shows 58, then you can be pretty sure that the transmitted value is skewed, but the raw hex value in the controller is correct.
If the code doesn't come up until 68PSI on the mechanical gauge, then you know the raw hex value is incorrect also, or Ford is using the converted value for setting codes.

tensixniner · Aug 23, 2011

Is the margin of error you guys are seeing (5-7psi) make a difference with respect to how the engine runs?
Or is this just a problem with tuning a wastegate where your using a different sensor for setup?

I thought the race tunes had safeties shut off ... overboost being one of them.

Spatel23 · Aug 23, 2011

I wouldnt say a problem but it does make a difference when tuning in gates.

mike@haller's · Aug 23, 2011

I don't think these trucks will set an over boost code. But it could just be the tuners are turning it off. The difference in boost levels doesn't effect the engine persay. But it greatly effects me tuning gates.