drive pressure

[sweetdiesel]

would installing a gauge in the exhaust manifold help to determine
Drive Pressure?

i was foolin around with the computer yesterday and built a exhaust
gas flow rate chart,using vane postion upstream pressure downstream pressure and downstream temp plus tubo inlet diameter

useless knowlege probably:rolleyes: :D but thought i would ask

[JOHNBOY]

Actually it should give us some really good info. I really hope to do a drive oressure gauge myself. I am real curious how things like different exhaust housings effect the pressure.

[sweetdiesel]

Actually it should give us some really good info. I really hope to do a drive oressure gauge myself. I am real curious how things like different exhaust housings effect the pressure.

cool, i geuss ill add it to the long list of things to do


this gauge if/when i install i would like to hook up to my EFI
anyone done this yet and/or the EGT wire?

[sweetdiesel]

where would be the best place to tap into? front / middle / back

couldnt you see like as high as 300 psi with big boost ?is there a ball park formula?

[turbo-max]

from what i recall, 1 1/2 to 2 times the boost pressure is ideal drive pressure, but most turbo applications are not that efficient and see 2~5 x's in the d/p

[The Neens]

where would be the best place to tap into? front / middle / back

I'd like to know as well...I'm gettin' interested in doing this...

[McRat]

I've never logged drive pressure yet. Something I've meant to do, but haven't.

You could also figure out drive pressure with 2 EGT probes. One pre turbo, one post turbo. You would assume pressure would be close to atmospheric at the post turbo and do the math.

The closer to the same temp, the lower the drive pressure.

[sweetdiesel]

http://www.autometer.com/cat_accessoriesdetail.aspx?vid=27


i was thinking about using this and tie into EFI with it so i could log the pressure

[Lennart]

Simon,

once you upgrade your turbo and have the vane position sensor unused you could hook it up there and just log that PID! No need to run wires inside the cab.
You could also do the same thing with the EGR feedback!
some of the gasser guys do this to log fuel pressure and I figured that we should be able to do the same. All you need is to locate some 0-5V pressure sensors...calibrate them and create a custom PID.
...but I see you already know as I was going to post a link to the thread over at the EFILive forum. :D

[sweetdiesel]

Lennart
THATS COOL!!! i just read some of that post on EFI forum

so i just use the AutoMeter sesnsor and use the calibrations in the vane position table? or how do i set the varibles?

[sweetdiesel]

Simon,

once you upgrade your turbo and have the vane position sensor unused . :D


that's a good enough reason to upgrade for me! :D

[JOHNBOY]

Simon,

once you upgrade your turbo and have the vane position sensor unused you could hook it up there and just log that PID! No need to run wires inside the cab.
You could also do the same thing with the EGR feedback!
some of the gasser guys do this to log fuel pressure and I figured that we should be able to do the same. All you need is to locate some 0-5V pressure sensors...calibrate them and create a custom PID.
...but I see you already know as I was going to post a link to the thread over at the EFILive forum. :D

Dooh!

One time it is bad to have a no emissions old school dumb turbo truck. I could change to a emission operating system but I would need to change the whole harness to? :(

I have been looking at a stand alone loggers like the ones from Corsa and RPM Performance. Any body know of any others?

[sweetdiesel]

Dooh!

One time it is bad to have a no emissions old school dumb turbo truck. I could change to a emission operating system but I would need to change the whole harness to? :(

I have been looking at a stand alone loggers like the ones from Corsa and RPM Performance. Any body know of any others?

you should still be able to ues EFI just need 5v of power to supply it
im going to investigate this more tommorow and let you know john

also im going to tap into the middle of the manifold

[Lennart]

The 5V reference voltage is already in the EGR and vane position connectors...

[sweetdiesel]

FYI here is another option for us:
http://www.dieselplace.com/forum/showthread.php?t=84698
but im going to try and build my own, im just waiting for a call back on some parts, ive also located a temp sensor that should have no issuse with hooking into EFI....cost not sure yet

[JOHNBOY]

Simon
Am I reading that thread correctly? You need V2 to use it?
Ugh! more money to throw at it.:D

[sweetdiesel]

John

i believe you can still use it with v1, but its a little different setup

[c_murray7313]

OK folks,

i have ane more spot in my truck to install a gauge, i already have boost 0-60psi, fuel pressure 0-100psi, pyro 0-1600, and a trans temp gauge. ive been thinking of installing a drive pressure gauge but am having a couple issues with this.

1)where am i supposed to tap into the exhaust.
2)what type of gauge am i supposed to use, boost gauge, electric pressure gauge?


any and all help is greatly appreciated. thanks in advance.


chris

[sweetdiesel]

OK folks,

i have ane more spot in my truck to install a gauge, i already have boost 0-60psi, fuel pressure 0-100psi, pyro 0-1600, and a trans temp gauge. ive been thinking of installing a drive pressure gauge but am having a couple issues with this.

1)where am i supposed to tap into the exhaust.
2)what type of gauge am i supposed to use, boost gauge, electric pressure gauge?


any and all help is greatly appreciated. thanks in advance.


chris

i use a 0-100 psi electric fuel pressure gauge

tap into the manifold on the opposite side of the pyro
BD manifold works great for this;)

its a good idea to use some tubing to come off the manifold so you dont wreck the sensor

ill post some pics of what i used tommorow

[sweetdiesel]

chris
here is a idea, get a extra 0-100psi sensor from autometer and rig it in so you can switch between you DP and FP
cheap mod that way:) or else use the 100psi for the DP and get a 0-30psi for the fuel press

[LarryJewell]

This would make a good DYI writeup Simon ;)

[Killerbee]

Larry, you should be able to do this with the scan gauge. You would need a 5V sensor that will stand up to the abuse.

[c_murray7313]

thanks guys, im prolly gonna do like simon said and get a 30psi fuel pressure gauge and use it for the fuel pressure and take the 100psi aguge and use it for drive pressure. id do the switch thing but i need to fill another gauge spot anyway. thanks guys.

[sweetdiesel]

Larry, you should be able to do this with the scan gauge. You would need a 5V sensor that will stand up to the abuse.

there is actually a couple ways we could do this:),I would love to set it up though my EGR valve and monitor it that way with EFI or you could simply run it directly to the V2


http://www.forum.efilive.com/showthread.php?t=2964

[MAXLLY]

Exposing ignorance again... I 'm not a turbo diesel guy, yet.

What is drive pressure and why monitor it? What will it tell you is happening?

Thanks.

[sweetdiesel]

well its basically the back pressure of the exhaust, and on the VVT its a key component to running a good tune IMO, also with larger turbos and twin set ups

ideal would be a 1 to 1 ratio( depending on turbo) or some where around there and vane posistion for us stockers plays a huge role, aftermarket turbos need timing and fuel adjustments to alter there drive pressure

when i installed the HTT mine would follow boost, when i had the stock on it would be double the boost and sometimes tripple:eek: Vane altering would make dramatic changes to this;)

[sweetdiesel]

ok, this is what I used

20" SS tubing
4'- 1/4" in hose something that can stand some heat atleast a couple hundred F
a connection to hook from the Exhaust manifold to the tubing
a connection to hook the hose to the tubing
a connection to hook the hose to the autometer sensor
a 0-100 psi electric boost or fuel press gauge
and ofcouse whatever you need to install a gauge ( wire, fuse )
hope this helps!:)

Thanks to Dale and his amazing picture taking.

[sweetdiesel]

ok, this is what I used

20" SS tubing
4'- 1/4" in hose something that can stand some heat atleast a couple hundred F
a connection to hook from the Exhaust manifold to the tubing
a connection to hook the hose to the tubing
a connection to hook the hose to the autometer sensor
a 0-100 psi electric boost or fuel press gauge
and ofcouse whatever you need to install a gauge ( wire, fuse )
hope this helps!:)

Thanks to Dale and his amazing picture taking.

[LarryJewell]

Thanks Simon :D

[MAXLLY]

sweet, thanks guys!

[sweetdiesel]

probably the best thing you guys could use is a hydraulic hose from John Deer
or even better a steam hose
i used the braided simply because ....it's so readilly availible for me
just basically find something good for heat and 100psi-200psi

home depeot may have some copper tubing for hot water tanks and plumbing
might be a good place to get the tubing


FWIW the lenght that i used it not carved in stone you could use longer or shorter,
The line wont get that hot as your EGTS, unless it is actually flowing through the line
but i would try to keep the tubing to atleast a foot or more.

here is a link to autometer gauges any of the 0-100psi fuel will work
http://www.autometer.com/cat_gaugesearch.aspx

[LarryJewell]

Bringing this back for more discussion :D

Simon, my new gauge should be in in a few days, you ready to make the tutorial ;)

[LBZ]

We need a "How to log drive pressure with EFI" tutorial too!!

[LarryJewell]

Maybe if everybody would PM Simon, he just might do it ;)

[sweetdiesel]

Maybe if everybody would PM Simon, he just might do it ;)

i would love to tie into the EGR 0-5volt


also,something i didnt realize is with the cold weather my SS tubing is freezing:confused: im geussing a little condesation and it sits in a low spot then overnight it freezes......who would of thought?


you got all the pieces you will need yet larry?

[LarryJewell]

you got all the pieces you will need yet larry?

actually I cleaned out my pm box and lost the list, would you mind re-sending when you get time :baby:

[sweetdiesel]

hose

tubing

electric gauge

basically once you find some tubing to use, find out what connection it is? is it NPT fitting or what? then you need to install this into the manifold and that will be a 1/8" npt so make sure you can install the tubing onto the 1/8" npt fitting coming out of the manifold

then on the other end of the tubing you will attach your hose, Again you will need to adapt to the hose from the tubing

then you will need to adapt to the hose to the sensor that will come with your gauge ( probably 1/8"npt or 1/4")


as for the hose try and find some good higher heat hose atleast good for 100f
i can grab a hold of my hose after the truck has been running and it dont burn me so it doesnt have to be that high of temp

but if you can, find a hose that is crimped fittings not hose clamped together.....if you can?

install the gauge and run the wires and sensor through the firewall and connect it to the hose

[LarryJewell]

hose

tubing

electric gauge

basically once you find some tubing to use, find out what connection it is? is it NPT fitting or what? then you need to install this into the manifold and that will be a 1/8" npt so make sure you can install the tubing onto the 1/8" npt fitting coming out of the manifold

then on the other end of the tubing you will attach your hose, Again you will need to adapt to the hose from the tubing

then you will need to adapt to the hose to the sensor that will come with your gauge ( probably 1/8"npt or 1/4")


as for the hose try and find some good higher heat hose atleast good for 100f
i can grab a hold of my hose after the truck has been running and it dont burn me so it doesnt have to be that high of temp

but if you can, find a hose that is crimped fittings not hose clamped together.....if you can?

install the gauge and run the wires and sensor through the firewall and connect it to the hose

OK, I printed the pics from post # 18, i'll carry those to the parts store :D

[LarryJewell]

probably the best thing you guys could use is a hydraulic hose from John Deer
or even better a steam hose
i used the braided simply because ....it's so readilly availible for me
just basically find something good for heat and 100psi-200psi

home depeot may have some copper tubing for hot water tanks and plumbing
might be a good place to get the tubing


FWIW the lenght that i used it not carved in stone you could use longer or shorter,
The line wont get that hot as your EGTS, unless it is actually flowing through the line
but i would try to keep the tubing to atleast a foot or more.

here is a link to autometer gauges any of the 0-100psi fuel will work
http://www.autometer.com/cat_gaugesearch.aspx

I thought in a different post you said not to use copper tubing :confused:, so is copper tubing ok instead of stainless "I'm assuming that is what you were refering to when saying SS"

Using copper tubing might make this a one stop shopping trip ;)

Where did you get the braided hose from?

[LarryJewell]

Larry, you should be able to do this with the scan gauge. You would need a 5V sensor that will stand up to the abuse.

Curious, how would this actually hook-up to the scan gauge and how would I program the gauge to read the pressure?:confused:

[sweetdiesel]

one thing larry when you find the tubing that will work, DONT try and bend it yourself unless you are good at that kinda stuff or you will end up crushing the tubing or kinking it
if you dont have acsess to tubing benders bend the tubing around a paint can or something like that so it will not kink

[sweetdiesel]

I thought in a different post you said not to use copper tubing :confused:, so is copper tubing ok instead of stainless "I'm assuming that is what you were refering to when saying SS"

Using copper tubing might make this a one stop shopping trip ;)

Where did you get the braided hose from?

i think it would be OK,im not sure i get stainless tubing from work so thats what i use

the braided hose..same thing get it from work FREEBIE;)

now for hooking it up to the EFI, i havent done this YET but you will need a calculated PID selected 0 volt = 0 psi and 5 volt = 100 psi or close to that idea anyway

hooking it into the EGR plug would be nice,it is a 0-5 volt allready
i posted a link to the thread a while back on how to do this,ill see if i can find it

or you could simply run the wires through the firewall and plug it in to the EFI using the orange plugs

this would be a huge bennifit to log it and not just see what your pressure is...so when you get it all figured out, you can show me how:D

[LarryJewell]

Waiting for KB to reply, he indicated that I could hook to the scan gauges, so, if that turns out to be easy, then hooking to EFI should be a snap.

My egr plug is taped off and just hanging there, Maybe i'll put it to use if I can figure it out.

[sweetdiesel]

larry, worst case scenario
http://www.autometer.com/cat_accessories.aspx?sid=37

[LarryJewell]

larry, worst case scenario
http://www.autometer.com/cat_accessories.aspx?sid=37

I think I just found my one stop shopping, thanks Simon:D

[Mike]

I think I just found my one stop shopping, thanks Simon:D

Sounds like your on a role Larry. Keep going and going and going. :D

[LBZ]

Pat was doing some messing around with it but I don't know how far he got or if he got it to work with his EFI. Hopefully he chimes in here!

[LarryJewell]

Sounds like your on a role Larry. Keep going and going and going. :D
Just trying to keep up with the Jones, err I mean Kimbles :D

[Killerbee]

Curious, how would this actually hook-up to the scan gauge and how would I program the gauge to read the pressure?:confused:

you have to find a high temp transducer, with a 5V scale

[sweetdiesel]

you have to find a high temp transducer, with a 5V scale


unfortunatly,i dont think a high temps sensor is needed as long as your not plumbing it right on to the side of the exhaust manifold

reason i say this, is mine was definatly frozen:( today i pulled the truck into the garage and after tinkering with some other things, i pulled off the sensor from the end of the hose and out came some water
started the truck and shot the most disgusting balck sooty water all over under my hood. plug the sensor back in and low and behold it works again

SO.... the moral of the storey is make the tubing exit the manifold in a all upward posistion,mine went down and then up:banghead: or option B live in sunny California

[Killerbee]

aaah, true that. OK, I've had the flu, and still do. A bit of a fog here.

Larry, I will find out how the scan gauges will interface. There were some little wiring harnesses that came with the scan gauges. Still have them?

[LarryJewell]

I think I kept them, i'll have to look this weekend.

[Killerbee]

You will find the inputs on page 3, they use the 2 harnesses

http://www.aeroforcetech.com/files/Interceptor_USER_MANUAL_rev_2_2.pdf



http://www.aeroforcetech.com/files/2_and_3_bar_MAP_sensor_kit_instructions.pdf

there is a routine that you go through on the gauge itself to calibrate the sensor for scan gauge use. You have to input a slope and an intercept. Don't worry if this means nothing to you, it is just the numbers that relate the linear voltage relationship. ANY 5V sensor can be used, as long as it is linear. we just have to determine the voltage/psi relationship, which is usually supplied by the sensor mfr.

[LarryJewell]

Is my unused egr plug a canidate?

[Killerbee]

It doesn't have to be unused. You should be able to take the 5V reference signal from any of the sources, MAP, EGR, MAF, Vane Position, etc. Splice and go.

If you have a male harness for an unused plug, all the better, no splicing. But you will only be using the 5V ref signal (usually red I think)

[LBZ]

EGR it is then!! I think most people could use that one!

[LarryJewell]

EGR it is then!! I think most people could use that one!

:stupid:

[Killerbee]

Looking forward to a logged result. Please get a baseline from a stock tune, stock charger. This is essential to compare against future modifications, inlets, tunes, chargers, etc.