Wow, this thing is incredible so far. I want to make sure I am not getting too excited for what may be the reality to come. I finally finished the AEM V2 install, tested it, and ran it.

1. So max boost 8psi (till break in and tune)
2. Max RPM reached 6500 (trying to limit it for a few hundred more miles)
3. Turns on at 2psi and max at 8psi
4. This is the 250cc nozzle
5. Ait sensor in stock location (fast acting triumph)

I let the iat get up to 52°c and started easing into some boost and the temp dropped quite rapidly to 27°c. That is 25°c drop! This is only distilled water. I felt no noticeable decrease in power. Is this miraculous feat only due to the low boost levels and keeping the rpms down? Can I expect similar results once I am running 12-14psi? Or will I have possibly jump up to the 500cc? Or is this an experiment and see kind of thing? I am border line on the chart as I want to push around 350ish to the wheels.
I want this as a safety net/cleaning device. Is this enough to provide steam cleaning action from what all you pros have seen?
I am so surprised that some of the old school guys haven't jumped on this.
This stuff is awesome! It should have been one of my 1st mods being I live in S FL!

 

If your IAT sensor is still in the stock location and assuming your nozzle is upstream, then some of that dramatic 25 C. drop you’re seeing is from the fluids contact with the sensor.

 

Where would be a better location to get a more accurate post injection temperature reading? Would using a closed element sensor be better for this situation?

 

If you’re not tuning with WI a post injection air reading is kind of academic imo. My observed results were in lack of coolant temp spiking after prolonged periods of boost, a little lower knock values and cleaner plugs.

Post #10 in this thread by the same OP —-> https://www.rx7club.com/auxiliary-in...usion-1137693/

 

I have AEM v2 runing boost juice. My fast air temp is at its original location. I added the system after tuning the car and the air temps drops really fast, but again the same as above. The air intake temp sensor most be getting washed with the juice. I will be having new turbo set up and I am not sure now if i want to tune the car with water meth ON. I was going to turn it up to 18 psi max with boost juice as my high boost setting.

 

I figured it had to be a lot of wash on the sensor. It is the open element type also. So now of course I am curious to the reliability of said sensor.... I know that was covered a few times on the forums, but I am not sure I ever saw a definitive answer.

I am not interested in tuning with this as I am in paranoid mode now and definitely do not want to rely on injection to save my engine every time I hit boost.

So another thing I know that's been covered many times is what happens when she is reading lower than normal. Worst case scenario should be it pumps in more fuel correct?
I am not really interested in moving my sensor. If it will dump in more fuel then I will not worry about mixing any meth in at all. I just want what you got Sgtblue.... added protection and cleaning. Especially since this thing will probably be a rich running car until I feel more comfortable with the pfc myself. I know it will be tuned pretty rich for safety. (Speaking about the cleaning attribute)
Maybe a closed sensor element. Still a fast responding, but not open?

 

Sorry just I re read your post and you have the same question as I do. I will try to look more into the element. Also I will make sure when we dyno that I actually post what kind of power loss or whatever I find.

Someone please correct me if I am wrong, but even with temp reading lower I do not see any danger only safety in this setup.

 

As I said in that earlier thread I’m not a tuner but yes, a lower iat reading would lead to a richer mix. Which obviously is safer than lean.
It’s up to you, but seems like in addition to lowering power, more fuel than is really needed will, to some extent, defeat the de-carboning effect of WI and make a cat work harder. And I don’t THINK a closed element IAT sensor will make all that much difference...especially during longer periods of hard boost.
If you were still rocking the OEM sensor you could’ve just reached under and unplugged it, leaving the OEM version in place. Then just extend the harness a few inches and plug it back in to the relocated faster one. But in your case you’d want to remove the fast-reacting sensor. It’s not that big of a job but I’d at least consider relocating it if you ever have to pull the UIM.

Note the green Bosch sensor just after the IC and the nozzle in the elbow...

 

From what I'm gathering, unless the sensor is shielded inside the manifold from getting wet entirely then there is no way to read post injection ait reliably. The sensor getting wet is skewing the reading. It would seem not paying much attention to that metric but instead just tuning for it would be the better approach.

The post injection air temp number becomes arbitrary because of the sensor being washed out. I'm not entirely sure at what point the air temp would be actual again. I would assume not too long after the injection stops.

 

Maybe bringing it on at a higher boost would help. I know srgtblue is on at 2psi if I remember correctly. That's what I have mine coming on at. I am having a hard time seeing the sensor getting saturated with that kind of velocity. I spoke to a "guru" about it and he seems to think that it is probably the air temp coming down quite a bit also, not just the sensor getting wet. He is not the biggest fan of all these "fast reacting " sensors too unless it is damn sure they are calibrated like the oem (which of course makes sense).
I understand your comment Srgtblue about negating the affect of cleaning if it is running even more rich, but at what afr is that actually a problem? I think if I can get my afr lean enough at cruise and it is rich enough to shoot flames (I don't really want it that rich, just an example) it should be fine. That's my "thought" which is definitely no where near fact.
Are you in the 10s afr on boost Srgt?

 

Personally, i don't buy into the you need to move the sensor debate. You want to read the air temps going into the engine. If AI lowers your air temps, that's what you want to read

 

I agree. I do however think it may show it a little lower than it actually is as the water probably hits it. I will keep it in stock location. All the new Triumph fast acting are all open elements. That is what I have and I heard it is reliable.
I will keep the set up as is. Again, I may have to switch to the 500 when the boost is up, but I will wait and see how it goes I guess. The way I interpreted the chart was only NA use the wimpy 250 lol. I will have to look at it again.

 

If water is hitting it, the nozzle may be too close to the sensor. You want a little distance to ensure atomization of the water, and not just for the sake of the sensor, but to get good mixture in the intake charge.

As for the nozzle size, using a smaller size (250) but triggering it on sooner will provide a constant smaller flow of water throughout your boost phase. I use the medium (500) nozzle that's triggered on at 7 psi, primarily because that's where my engine lives (over 7 psi)

 

1st pic is where I got the boost from for the controller and well 2nd speaks for itself. 1st time I ever threaded something. Wasn't perfect by any means, but it is extremely tight lol.
what made you bring it on at 7psi Tom? Instead of lower? Your not making more than 12psi correct? Have you experimented with it? I never saw you write much about it and am still a little confused with your "high egt" if that is actually what was happening. I thought you ran on the rich side.
Again I may have to swap to the 500. I won't know until later when it is putting out some good power.

 

Have the sensor provide a meaningful reading of the AIR temp, yes. We agree. But I don’t see how it can if the water, no matter how well atomized, is coming into direct contact with it. And I could see the artificial reading being lowered even more if the op moved to a methanol mix instead of just water.
I don’t know...it IS erring on the safe side, but like Howard suggested, why have AI screw with things when it’s so easily avoided.

 

I guess in the big scheme of things it is easy. I would have to change my cold side pipe for a thicker one or find someone to weld on a very thin piece which no one around here seems to want to do.
Now let's say I move it. I have actually found a bit of oil on the inside of the hot and cold ic pipes. This is on the old and new turbos, rebuilt "pettit" and a brand new Mazda motor. The sensor will probably get oil on it which may increase the temp. This was kind of my deciding factor to just keep it where it is and errrr on the side if caution.
I 100% get your point. No idea why Mazda put it there to begin with. I have read a few theories, but still....... I just need to make sure I have a good tune and I think the carbon won't be too much of an issue.... I hope.

Btw Srgtblue, your set up seems as if it's been working for awhile with 0 issues so I would say it is pretty proven.

 

About 13-14 years now...and about 50k miles. Had to replace a Hobbs switch (pressure switch) once. About $25. And the occasional filter for maintenance.

 

I was speaking of your motor. You have quite a few miles on it if I am not mistaken.... I am almost wishing I kept the oem seals with this water inj as I am only looking for low power and longevity. Low power like 325+ lol which should still be pretty fast.