roastin240

iTrader: (13)

ForceFed - Thanks for the calibration curve, this is what I wanted to see. I just ordered my MS3 Gold Box setup, so I do not know the capabilities yet...but it seems that you could create a correction factor to be calculated for the lambda being observed and recorded, read a pressure transducer pre-turbo, and set up an IF statement: IF Lambda >1 use K=0.47 and IF Lambda and use the calculation to give a new lambda value.

I wonder if narrowband O2 sensors are more durable? I could potentially use narrowbands for part throttle closed loop and resort to a wideband downstream of the turbo for initial tuning and CL WOT corrections, as well as engine shut down safety int he event it goes lean.

roastin240

iTrader: (13)

[/QUOTE]

I would probably want to run one of these regardless on my downpipe as well considering I am putting it less than a foot off the turbine housing (I guess I could go further downstream with it).

Where are those sold? Thanks

stevieturbo

What complete and utter nonsense.

Forcefed86

iTrader: (4)

Narrow band would be fine.

This is the one I got.

http://www.ebay.com/itm/Innovate-372...NS~t2C&vxp=mtr

Forcefed86

iTrader: (4)

roastin240

iTrader: (13)

The graph was posted....that was concrete data from the sensor manufacturer. It looks like lambda output is skewed when pressure increases or decreases in either direction of 1 bar absolute.

boostedxs

thanks for the input stevie. seems like we're having a tussle here haha I like it. I always try and keep my mind open so I can learn and maybe come up with new things to help my builds. I checked out that 02 sensor extender you guys posted on here, looks like a decent product that I could use on my post turbo wideband since I have mine kinda close to my turbo (bumper exhaust). my only question is does this affect sensor sampling any since the sensor no longer dips into the exhaust like it normally would.?

M_Minnick

iTrader: (1)

AEM"s 4-channel controller has built-in pressure compensation:

http://www.aemelectronics.com/?q=pro...afr-controller

stevieturbo

And if people would open their eyes and read. That's exactly what you can use a sampling chamber for which takes the pressure aspect away which is why his comment about the use of a sampling chamber was complete and utter nonsense. And that's me being polite about it.

kingtal0n

iTrader: (1)

I am sure some sensors are better than others for this.

But the cheap $150 AEM for example, and similar, will not work at high temperatures (near the turbine). I have verified this, dyno wideband showing 15:1 and in car wideband showing 11.8:1 when the EGT got out of hand.

Forcefed86

iTrader: (4)

Maybe I’m misunderstanding your “chamber”? Any area pre-turbo (regardless of the orifice size leading to it) will have the same amount of pressure as anywhere else in the system. That’s how all sealed pressure systems work. How are you suggesting it would work otherwise? Maybe I’m missing something? Draw us a diagram of what you’re talking about.

roastin240

iTrader: (13)

Correct...pressure doesnt drop from just being in a chamber, even if it was located 5 feet away from the exhaust and had a small orifice feeding it. You would have to bleed off exhaust to reduce backpressure, and at that point the pressure would be the same everywhere in the system again...so no gain from a pressure standpoint would be achieved. Are you unaware of this Stevie?

stevieturbo

If you believe this, may as well rip out your entire boost control setup, as it will never work. Same principals apply

It is NOT a sealed system, air will always move from an area of high pressure to low pressure. You control that movement via orifice size, exactly as you do with your boost control.


Here is one install ( not mine ). Small line to the chamber, larger discharge back into main exhaust. This results in NO pressure build up in the chamber.





And another

[/quote]

And another

69-chvl

iTrader: (11)

And another

[/QUOTE]

Very interesting thanks for posting Stevie.

kingtal0n

iTrader: (1)

seems like an unnecessary excessively complicated apparatus which requires several additional holes and fittings to be added to parts which already have a tendency to leak.

Might have a racing application, but even then I would want things much simpler than that. thumbs down for daily drivers thats for sure. And FWIW if you isolate something from the temp of the exhaust like that, then it technically is no longer installed directly to the manifold (the question was/is: can I install a wideband to the manifold directly, answer is NO: You must isolate it somehow, to a cooler/lower pressure area, so this really just proves that same original issue is true, they will not tolerate well being directly bolted into an manifold.)

its like saying "hey guise, can I run a lawnmower with ethanol?" and half say "yes" and half say "no", the "yes" people are right because of course it will work, provided that certain conditions are met (apparatus is provided). The no people are also right because, those conditions have not been met in their eyes yet, without the additional apparatus. So no, you cant just put ethanol in the tank, and no, you cant just bolt a wideband into a pre-turbo manifold and expect it to work like that either.

stevieturbo

What parts have a tendency to leak ?

If you build it ****, then yes I guess it could leak.

And no, nowhere was it asked "can I install a wideband to the manifold directly"

Which goes back to my comment about people opening their ******* eyes and reading.

Forcefed86

iTrader: (4)

You're off your rocker man! And 100% wrong.

For one, those are all post turbo, none of them are pre-turbo which is what we are talking about... Those are setup to reduce flow/temperature, and will have zero effect on a pressure reading pre-turbo.

The WG controls the entire systems pressure pre-turbo. It takes X pressure to make Y boost. What ever that pressure is, it will be a constant through out the entire hot side pre-turbo. I don't care if you run a 10ft length of pipe of the manifold and put a pressure sensor in it. It will read the same as the rest of the system.

Just like my 1/4 brass line with 20 coils in it leading to my turbine drive pressure sensor would read the same as if it were tapped directly into the manifold runner.

kingtal0n

iTrader: (1)

It might not leak if someone like you tries it. The forum is filled with novices and experts (mostly novice) though, so anyone that see such a thing and thinks they "need" it would probably wind up with a leaky exhaust system. Just like a first timer installing a $38 EGT bung into a manifold. Now you have a new spot to leak. The expert knows how to get it done, use a high quality part etc... but most of the novices are going to wind up with new holes that leak.

Now, My real concern is that this setup is completely unnecessary. A single wideband 3-5 feet behind a turbine is good enough for the majority of high output engines, even at 2000rwhp I would be ok with one in the car and one off the dyno for accuracy comparison.... I would never intentionally add a bunch of holes/plumbing to my already complicated turbo system. Not when a single hole/sensor mounted 5 feet away is good enough.

lurker1978

It seems to me that the sample chambers would work, since the orifice is smaller on the inlet than the outlet, and the chamber itself should pull some vacuum from being dumped in the post turbo exhaust no? Wouldn't that eliminate most of the heat/pressure concerns?

stevieturbo

It's the VERY BASIC principal that some dont seem to grasp, air will move from high pressure to low. And yes you're correct except it isnt reliant on vacuum as such, just the pressure differential.

Forcefed seems to think...

Exhaust manifold pressure pre w/g, ie before the control orifice is the same as the w/g discharge either to atmosphere or into the DP, which of course is nonsense.

He also seems to think in a basic boost control setup, manifold pressure is the same as that applied to the w/g chamber to blow it open after the control orifice bleeds some off.....which is also totally incorrect. If he was correct, none of our systems that vent air after a control orifice would ever allow us to alter boost over basic mechanical spring settings.

Hopefulyl he'll take a minute or more to read what he just wrote and realise how wrong he is.

Even more baffling is why he seems to think something is post turbo, when the connecting lines to the exhaust manifold...ie pre-turbo are there in all their nasty glory for those with eyes to see.

And if someone really wanted to mount them "directly" onto the hotside, they could also do this, just extend the sensor up a couple of inches from the hotside, and as you've said a small orifice to supply air to the sensor then route the larger diameter discharge back into the DP.

It's SIMPLE, SIMPLE, SIMPLE.