100 PSI Boost into ECM feed.

[McRat]

Something that bugged me ever since I started playing with Dmaxes is that the ECM will only report about 30PSIG boost stock. The sensor itself caps out at about 40psig. But as soon as you start playing with aftermarket chargers, neither range is much good.

First I played with sensors fed in the EXT ports on EFILive, but it proved to be cumbersome. Next I played with reading it into the EGR Position sensor, and it works, but it still isn't "right".

So now I purchased a Honeywell sending unit that has the same characteristics as our stock sensor.

It didn't come with a wiring diagram:

Case is not grounded.
Black wire is ground.
Red wire is 5 volts supply.
White wire outputs:
.500v = 0 psig
4.500v = 100 psig

Factory boost sensor, LLY is:
Orange/Black is ground
Green is output 0-5v
Gray is 5v supply

Hook Black-Black
Hook Red-Gray
Hook White to Green

Rescale Boost Sensor using EFILive and Voila! If you look at the pictures, see the BOOST. One is room pressure (14.7 maybe), the other is 90psig regulated air from a compressor.

 

[sweetdiesel]

Good Idea! I know we done some playing with the voltage but wasnt the greatest
this idea is better!

How much for the sensor?

 

[McRat]

Now to road test when it stops raining.

 

[McRat]

Sensor is ~$75, but it's a really high quality sensor. Made for industrial apps and is thermal compensated, and internally protected.

 

[McRat]

When I road test it awhile, I'll do a better writeup, and include the P/N for the sensor.

 

[sweetdiesel]

Sensor is ~$75, but it's a really high quality sensor. Made for industrial apps and is thermal compensated, and internally protected.

I spent more on lunch today

When I road test it awhile, I'll do a better writeup, and include the P/N for the sensor.

Cool thanks

 

[Cougar281]

Nice! I've wondered what could be done when upgrading a VNT to say a cheetah, and pushing 40-50psi. "Desired boost" tables wouldn't be very usefull with the stock sensor.

 

[Kat]

What I found interesting, is on the Boost Sensor Scaling, it indicates a 72.5 (absolute) limit, or about 58psig. But that limit apparently isn't really there.

(posted by Pat)

 

[dmaxlover]

Is any fabricating necessary to use this new sensor?

 

[McRat]

This version is 1/8 NPT, so you just drill and tap somewhere, or use a SuperDiesel manifold ring. The other versions I tested were more complex and not really race quality.

 

[slowlmm]

Thats funny lol pat i asked you about this about 6 months ago and you told me it was a waist of time :hello: good to know theres aftermarket sensor out there that will work. for guys who dont want to run guages or just one digital one that does it all lie the insight

 

[JoshH]

Hmmm, sounds very interesting.

 

[McRat]

6 whole months?

I've been dinking with this on and off for 2-3 years, and very recently Honeywell came out with a sensor that is perhaps usable.

If you want, I will sell you a few sensors that didn't work.

 

[McRat]

Here's the "Wet Dream" - To capture boost and EGT's in datalogs without any EXT feeds when running more than 30PSI boost.

By the end of the week, I should get it all finished up. Finally.

 

[JoshH]

How are you gonna get the data from the EGT sensor into the ECM? I saw you found a couple of LMM EGT sensors, but how do you capture the data from it without external inputs?

 

[McRat]

How are you gonna get the data from the EGT sensor into the ECM? I saw you found a couple of LMM EGT sensors, but how do you capture the data from it without external inputs?

I'm going to feed it into the EGR position sensor, and make a custom PID.

 

[JoshH]

Cool! I'm way interested in seeing how all this works out. I wonder if there's a way to get drive pressure incorporated into the mix somehow?

 

[McRat]

Cool! I'm way interested in seeing how all this works out. I wonder if there's a way to get drive pressure incorporated into the mix somehow?

Drive pressure is something you only need data on when you first set up a truck. I wanted to feed that into the Vane Position Sensor, but I could not get that to work.

You could still feed that into another sensor, perhaps IAT?

 

[sweetdiesel]

Cool! I'm way interested in seeing how all this works out. I wonder if there's a way to get drive pressure incorporated into the mix somehow?

Drive pressure is something you only need data on when you first set up a truck. I wanted to feed that into the Vane Position Sensor, but I could not get that to work.

You could still feed that into another sensor, perhaps IAT?

Maybe on a lly you could make use of the intake heater pins on the ECM??
0-5 volt???? I see that we have the left over tables from the lb7, But dont know if you can log them??

Lb7 people should be able to somehow use the EGR pins also?

This post is a whole lot of :dontknow:

 

[LarryJewell]

Drive pressure is something you only need data on when you first set up a truck. I wanted to feed that into the Vane Position Sensor, but I could not get that to work.

You could still feed that into another sensor, perhaps IAT?

or if you are constantly playng with tuning