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Discussion Starter #1 (Edited)
With all the talk of conservative ECU tuning to prevent detonation when the engine is run hard for extended periods, and also the concerns over intake valve coking in direct injection applications, I'm thinking a water/meth injection (WMI) system might be the answer to both concerns.

My 1st question involves GM's drivetrain warranty-would WMI void it? My 2nd question involves how the stock ECU would respond to such a system? Ultimately, what are the downsides?

JR has already mention the washer tank could double as the WMI storage tank, needing re-filled typically when fuel is added. As I understand it, the solution would only be sprayed under boost conditions. Cost would be only $2/gallon, unless you wanted the fuel boosting effects of 50% methanol; then it's $10/gallon at Home Depot. The systems themselves can be put together with quality components for around $240.

Let the discussion begin....
 

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My first thought is that you'd want to change the tune to compensate for the methanol/water injection to gain the most benefit as well as to not fool the existing tune into something unexpected. At that point you would be potentially affecting the engine warranty. My take is once they get more real world data, there will be GM updates coming to help mitigate this 'issue'
 

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The control units from GM are reported to have adaptive learning characteristics. Supposedly, after you drive the cars for a while, they learn your driving style, and they become more like what you want. I don't know if this is true or not.

What I do know for a fact is that my wife's Cadillac ATS has this ability. We live in a very hilly area here in NorCal, and there is one particular long hill near our house that we drive on almost every day. In the beginning, the car would fly down this hill if the car was in automatic mode unless you hit the brake pretty much the whole way down. Not liking this, I would always put the transmission in manual mode, and not let the car go any higher than fourth gear (sometimes third, sometimes fourth, but NEVER allowed it to go higher than fourth).

The wife, however, never puts the car in manual mode.

After many weeks I noticed that even the wife no longer had to hit the brakes on that hill. So I tried it in automatic mode as well. Sure enough, the transmission would not shift up any higher than fourth on that hill anymore if you touched neither the accelerator nor the brake.

It learned what I was doing to it, and now it does it on its own. I was thoroughly impressed.

Based on this, I believe what I have read elsewhere about this ECM issue on the Z06.

Drive it like the owner's manual says (translation: DO NOT BABY IT ALL THE TIME). Yes, you need to keep it under 4,000 RPMs, but you also need to regularly visit 3,900 RPMs. Note that the owner's manual clearly states that it needs to be driven in a mixed way, and if someone babies it, they are not mixing it up. So, do what you are supposed to: mix it up. Visit 3,900 RPMs regularly during break-in, while observing all the other instructions about how to break it in (go easy on the brakes for 200 miles, et cetera).

After you pass 500 miles, visit just a little south of redline. Drive it like you want it to be driven. Give it a little time to learn what you want from it. I would almost be willing to bet it will respond with what you want, and you will not have to change a thing except let it know what you want, and give it some time to learn.
 

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Is methanol corrosive to seals and gaskets the way that ethanol is? Would the combustion products adversely effect O2 sensors? Would you run the injectors after the blower?
Water/meth has been on my 1999 C5 as a testpig since 2000 and engine oil samples have been sent to Blackstone labs many times to be tested
and reports say all is fine.
C5s were not even designed for Ethanol and the results shows even after 14 years of water/meth use that there is zero degrading of any parts.

In theory, at recommended quantities, most of the mixture is evaporated before it hits the combustion chamber.
Also, Meth injection only takes place at higher engine load levels minimizing cylinder wash concerns.
Engines that have been torn down after several years of water/methanol usage have shown no wear issues only clean combustion chambers, i.e no carbon buildup

Keep in mind your not talking about 100% Methanol flowing through parts but the fluids being forced through 1 meth nozzle under around 200 PSI is
a mist and being 50 % of that is water vapor is gone before airmass is in the cylinder

At best your only talking about 600 mL a minute flow nozzle and that is only when you have the controller commanding w/meth functional which is mostly above lets say 4,000 RPMs.
Your installing only one nozzle into the intake airmass stream and then that goes directly into cylinder so small amounts of Methanol is not flowing or passing through hoses, fuel injectors, etc

I have at least 100 tuning customers with Corvettes from N/A to boosted engines that also have w/meth for several years we monitor and none have any part degrading due to w/meth use.
 

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With all the talk of conservative ECU tuning to prevent detonation when the engine is run hard for extended periods, and also the concerns over intake valve coking in direct injection applications, I'm thinking a water/meth injection (WMI) system might be the answer to both concerns.

My 1st question involves GM's drivetrain warranty-would WMI void it? My 2nd question involves how the stock ECU would respond to such a system? Ultimately, what are the downsides?

JR has already mention the washer tank could double as the WMI storage tank, needing re-filled typically when fuel is added. As I understand it, the solution would only be sprayed under boost conditions. Cost would be only $2/gallon, unless you wanted the fuel boosting effects of 50% methanol; then it's $10/gallon at Home Depot. The systems themselves can be put together with quality components for around $240.

Let the discussion begin....
If we split this into 2 parts

1. Use of the water/Methanol will prevent PCM having to yank timing due to hot air temps, engine knock or AFR too lean
That means preventing performance loss and no tuning of PCM is required as PCM will auto adjust as 02 sensors reporting AFR and IAT sensor reporting
lower temps.

2. Gaining performance - since the w/meth is going to achieve a much better charge to cylinders and reducing knock, raising the octane and richer charge to cylinder then gains of lets say 30 plus HP can happen but requires a tune because this would allow us dialing in more timing and able to lean the existing AFR up

You deciding on which then would dictate the flow size of w/meth nozzle you choose and what you use as the trigger when w/meth is on
Simple trigger of w/meth pump could be using MAP and trigger is when negative ( when boost is on)
Or use of a controller like I use that has a processor that monitors MAF, MAP and one fuel injector and auto calculates engine load/RPMs to command how much w/meth flow
Using Pulse Width Modulated (PWD) voltage to electric pump then controls if the pump flows at 160 PSI to 220 PSI which controls less or more w/meth flow through nozzle.

On average w/meth kits with muti stage controllers vendors charge about $500 for a complete kit.

Oh another reason to share the WW tank is it has a low volume trigger since on dash so you'd know if fluid needs to be filled.
Other then that the only maintenance needed is maybe once a year is clean the little filter on nozzle if using -20 degree winter WW fluid.
 

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Discussion Starter #7 (Edited)
After reading the Snow WMI site, it appears WMI will void your drivetrain warranty, as it enhances engine performance/increases power.

Well, at least those guys playing with their ECU, already voiding the warranty, can add WMI and ensure their intakes valves stay clean.
 

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Water Meth would most likely give grounds to void warranty as all it takes is a solenoid to stick open and you could hydro-lock....but that would be extremely rare. Running a good system with MAP sensor activation, etc. and 50/50 mic would work with a tune as is on any FI engine if used with a smaller nozzle, and the cooling benefits are great. We prefer to use it 100% Meth (or maybe 10-20% water) so it is a fueling supplement as well. Methanol is very corrosive, and is a sponge for water from the atmosphere. Long tern, any un-coated aluminum components will corrode from contact over time.

Using 100% methanol (contact Julio form Alky Control....he is the expert to Meth injection as I am to crankcase evacuation.....has probably forgottem more than I even know on the subject. Tell him tracy from RX reffered you. He can answer any possible question....the guy is a true genius on the subject) we figure it in as a fuel supplement as well as a cooling agent. Getting to much water entering the combustion chamber will contribute to spark blow out as well..

If you truly want cooler IAT2 temps, look at our Super Chiller system for any water to air intercooler. in less than 3 minutes, we drop IAT2 temps to 30-50*F below where it operates stock. On a dyno, thats 40-45 RWHP on a ZL1, ZR1, or CTS-V, GT500. I predict similar with the new Z06: (Watch ambient air temp, engine coolant temp, intercooler coolant temp, and IAT temps (IAT2, measured under the intercooler)

This only adds app 12-14# weight, never needs a refill of anything, always runs anytime the AC compressor is on, and for track use simply engage "competition mode" and it shuts off freon flow to the cabin so no water to drip on the track. Less heat related stress on all parts, and for the tuner crowd, you can add more timing and fuel for even more power.

 

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A stuck solenoid itself would not cause any real flow as the pump would be off when controller is not commanding flow

Only solenoid that is used would be a safety backup so that when pump is off any natural gravity flow is prevented by the fluid hose to intake
has the fluid flow solenoid off.

This is only a issue when running boost or bad install where nozzle is low to gravity flow

Cheap high profit kits are the big problem as they only use one trigger point such as MAP or angle of TPS

Use a smart controller which monitors MAP, MAF and fuel injector which assures flow is only when commanded and much quicker stopping the flow when TPS is on decel

Search internet as all USA and England testing during WW-II is zero gains from using 100% Methanol,
is a much higher user cost and was found best case is 50/50 W/Meth ratio

As to costs, if mostly street driven then maybe use 1/2 gallon Methanol per tank of gas, or if using WW fluid that is about 4 bucks a month or less then
$ 60 a year
Cheap protection for engine long term, cleaner internals of engine and good performance gains
 

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A stuck solenoid itself would not cause any real flow as the pump would be off when controller is not commanding flow

Only solenoid that is used would be a safety backup so that when pump is off any natural gravity flow is prevented by the fluid hose to intake
has the fluid flow solenoid off.

This is only a issue when running boost or bad install where nozzle is low to gravity flow

Cheap high profit kits are the big problem as they only use one trigger point such as MAP or angle of TPS

Use a smart controller which monitors MAP, MAF and fuel injector which assures flow is only when commanded and much quicker stopping the flow when TPS is on decel

Search internet as all USA and England testing during WW-II is zero gains from using 100% Methanol,
is a much higher user cost and was found best case is 50/50 W/Meth ratio

As to costs, if mostly street driven then maybe use 1/2 gallon Methanol per tank of gas, or if using WW fluid that is about 4 bucks a month or less then
$ 60 a year
Cheap protection for engine long term, cleaner internals of engine and good performance gains
True. Without the pump running it would not run, just dribble whats in the line. Alky Controls systems all use MAP sensors....quality is first rate. We use meth injection on most of our high hp FI builds, but for the TVS style top mounts, the RX system is about the same cost as meth injection and it is constantly cooling all components and never needs anything filled or serviced. Anytime the AC compressor is running, the chiller is. And the weight is minimal (close to the same as a meth kit) but no worries about running out, corrosion, etc.

Here is the first one we did on a corvette years ago:
 

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Discussion Starter #11
That chiller video is impressive. Guessing that would also void the warranty & not clean the intake valves. But, another great option for those who will be voiding their warranty with ECU tuning anyway.
 

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True. Without the pump running it would not run, just dribble whats in the line. Alky Controls systems all use MAP sensors....quality is first rate. We use meth injection on most of our high hp FI builds, but for the TVS style top mounts, the RX system is about the same cost as meth injection and it is constantly cooling all components and never needs anything filled or serviced. Anytime the AC compressor is running, the chiller is. And the weight is minimal (close to the same as a meth kit) but no worries about running out, corrosion, etc.
I can see where your Chiller system makes much sense, but I have a question:

Does the LT4 ECU make its decisions (to back off timing, etc..) based off more or less the inlet air temperature? If so, does that mean that timing may be backed off by the ECU even though the compressed air temps are low?

(Forgive me if I am missing something. I can't find much data regarding the location of the IAT sensor(s). Is there one for incoming air and one for air temp after SC compression?)
 

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That chiller video is impressive. Guessing that would also void the warranty & not clean the intake valves. But, another great option for those who will be voiding their warranty with ECU tuning anyway.
Correct. This will absolutely void the HVAC portion of the warranty as it is getting changed quite a bit, but can be un-done back to stock if needed, but not easily. This is for the ones that want the benefits and are not concerned on the HVAC warrranty, or have a Mod friendly dealer.

I can see where your Chiller system makes much sense, but I have a question:

Does the LT4 ECU make its decisions (to back off timing, etc..) based off more or less the inlet air temperature? If so, does that mean that timing may be backed off by the ECU even though the compressed air temps are low?

(Forgive me if I am missing something. I can't find much data regarding the location of the IAT sensor(s). Is there one for incoming air and one for air temp after SC compression?)
Yes. All GM are around 110-115 *F IAT2 temp before they begin to pull timing, at 150* it is 3-4 plus, and at 200 it is 8-10*...and that is substantial. The PCM/ECU does this to protect the engine from heat associated detonation and like many of the "nanny's" is for the good of the engine. You will find 2 sensors, basically in the same location as the ZL1 Camaro, CTS-V Caddy, and the ZR1 C6. There are 2 main IAT sensors. IAT1 is located in the MAF assy, and the IAT2 is in the lower plenum measuring temps downstream of the intercooler.
 

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This thread has taken an interesting turn with the Chiller.

I don't want to stay off topic, but this is an interesting discussion.
 

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Yes. All GM are around 110-115 *F IAT2 temp before they begin to pull timing, at 150* it is 3-4 plus, and at 200 it is 8-10*...and that is substantial. The PCM/ECU does this to protect the engine from heat associated detonation and like many of the "nanny's" is for the good of the engine. You will find 2 sensors, basically in the same location as the ZL1 Camaro, CTS-V Caddy, and the ZR1 C6. There are 2 main IAT sensors. IAT1 is located in the MAF assy, and the IAT2 is in the lower plenum measuring temps downstream of the intercooler.
Thanks. Got it.
Another set of questions for you:
So from what you are saying the IAT2 is what controls much of the timing pull off as compared to the IAT1?

I ask because I live in Arizona and in the summer the temp at the MAF assy IAT1 will be at least 115+??? much of the year considering ambient in the 100+ range, plus a hot car, hot engine and hot pavement. The Chiller will cool down the IAT2 temps, but will the ECU still pull the timing due to the hot reading at IAT1?
 

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Thanks. Got it.
Another set of questions for you:
So from what you are saying the IAT2 is what controls much of the timing pull off as compared to the IAT1?

I ask because I live in Arizona and in the summer the temp at the MAF assy IAT1 will be at least 115+??? much of the year considering ambient in the 100+ range, plus a hot car, hot engine and hot pavement. The Chiller will cool down the IAT2 temps, but will the ECU still pull the timing due to the hot reading at IAT1?
Yes, the ECU will take data from both IAT sensors.....and the IAT1 sensor will mainly give cold runing/cold start enrichment but can also trigger timing pull to protect. But the IAT2 temp is the one it will default to as the real data for timing pull.

The goal with Meth injection is two fold, cooling the intake air charge, and if using mainly methanol, a fuel delivery supplement to also assist in enrichment. The RX Super Chiller only cools intake air charge. Any time you are compressing air, a good amount of heat is generated. The hotter the air charge, the more this air expands, and the less room for oxygen molecules. Without dense oxygen rich air less fuel can be burned and less power is released. The nice thing about the chiller is only 12-14# added weight, and no filling with liquids, etc. and it is always cooling reducing heat related fatigue of all parts and far less chance of detonation. On the port injection engines of past, we found that under 45*F it caused fuel to begin to re condense before combustion....so we kept the temps 50*F or above. With DI, no issues so can even run cooler. But Methanol with it's ability to give a slightly richer A/F mixture under max boost is a plus the Chiller doesn't give.
 

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Possible warranty issues aside, if the rumored Z06 "overly aggressive pull timing when temperatures rise" issue is in fact true, I would give the chiller very serious consideration.
 

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What is being called IAT1 is built within the MAF is what PCM is using for it's calculations for most engine conditions

IAT2 within the intake manifold main purpose is for PCM boost control adjustments and the trigger window to command the inner cooler's electric pump
It is cooling the air ( after MAF) but is restricted to other conditions such as total temp of engine bay.

Really consider IAT1 as IAT for airmass and how humid that air is and what being called IAT2 is really MAT ( Manifold Air Temp) Which is what C4s had.

Any issues due to the heat by compressing the air is handled with Additional tables in the PCM so there is many boost tables related to
air, fuel, timing added to what PCM is doing for normal non boost engine conditions, thus the total changes are additive to normal feedback sensors
plus MAT and ECT

Water/Meth is a simple process that also means less parts to breakdown, the electric pump on my 1999 C5 is now 14 years old and still fine
that leaves really the w/meth fluid hose and nozzle which can last many years.
Also W/meth can be dialed down or even turned off by a switch when in cold weather.

Again the water cooling is one part, the Methanol is boosting the cylinder charge with even cooler temps and raising the octane level to reduce knock
which is really what PCM is doing by reacting and yanking timing.
Since it is a external system to the engine it has no ill effects to driving if it was to fail or ran out of w/meth fluid, PCM would react as normal for knock
where other air cooling designs if failing makes it harder to correct like if out of town and finding replacement parts

Being W/meth is after the MAF it cannot effect MAF's output as to airmass, calculated line pressure, torque and load
 

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Hi JR.,

Some questions for you.

I thought MAT was IAT1. I have been reading many posts and am still confused, being a Newbie.

I was under the assumption that IAT1 was at the Mass Flow Sensor and that IAT2 was in the manifold, after the intercooler.
I also thought that some of the problem with the Z pulling timing was due to the IAT2 reading getting hot.

I have seen some data by others that show that IAT2 doesn't go up much, but I don't agree. Compressed air always has a large temperature increase, especially given the fact that the air is being compressed in a super hot "chamber" called the engine. I have seen data by others, showing a significant increase in IAT2 temp's on other cars (new supercharged Camaro I believe) as soon as the supercharger pressure builds.
Others have shown that an intercooler chiller drops the IAT2 significantly, which I would imagine would keep the car nannies at bay from both a temp standpoint as well as a knock sensor standpoint, since the charge temperature is lower.

Like I said, I am a newbie in terms of the Z06 engine, but I don't think I am the only one confused over the data.
For me. and I think others, the issue isn't a problem, it is what do we have to do to get higher performance.


Dave
 

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Hi JR.,

Some questions for you.

I thought MAT was IAT1. I have been reading many posts and am still confused, being a Newbie.

I was under the assumption that IAT1 was at the Mass Flow Sensor and that IAT2 was in the manifold, after the intercooler.
I also thought that some of the problem with the Z pulling timing was due to the IAT2 reading getting hot.

I have seen some data by others that show that IAT2 doesn't go up much, but I don't agree. Compressed air always has a large temperature increase, especially given the fact that the air is being compressed in a super hot "chamber" called the engine. I have seen data by others, showing a significant increase in IAT2 temp's on other cars (new supercharged Camaro I believe) as soon as the supercharger pressure builds.
Others have shown that an intercooler chiller drops the IAT2 significantly, which I would imagine would keep the car nannies at bay from both a temp standpoint as well as a knock sensor standpoint, since the charge temperature is lower.

Like I said, I am a newbie in terms of the Z06 engine, but I don't think I am the only one confused over the data.
For me. and I think others, the issue isn't a problem, it is what do we have to do to get higher performance.


Dave
Hi Dave
your not confused, your right on

As I posted the MAF is IAT and BEFORE the supercharger
MAT (Manifold Air Temp) is in manifold and would report the hotter air that supercharger compressed which heats the air

Simple in that is true and why GM adds a water cooled inner cooler that is also commanded on by what MAT reports

PCM is biased as to what IAT, MAT ( air temps), and ECT ( engine coolant temp )
Those 3 feedback sensors will slant the PCM as to what it commands as to timing (spark) and fuel injector flow

Notice in looking at below snapshot of few LT4 tables, if IAT is around 160 degrees PCM is already pulling timing about -6 degrees
and as MAT values increase then PCM adds more fuel injector pulse width ON time to up the AFR

The whole purpose water/meth exists is the ills of what boost does in heating the air up making cylinder charge worse

We do not spray w/meth before the MAF/IAT as the air is cooler there ( thus IAT would report lower) and effect MAF output as to airmass
We put the w/meth nozzle ( 90 degree type) and shoot the mist right through the throttlebody as the water will pull more heat out of the hotter manifold heated air, leaving then the methanol to be pulled into the cylinder with the colder airmass.

Now that allows IAT and MAT to report correctly and due to effects of w/meth MAT will report the lower temp and thus PCM will not have as much negative effect of hotter boost air temps

As mentioned the hotter the air gets the more it expands, hence less molecules per volume which is crappy burn in cylinder so PCM of course would yank spark and increase fuel and react to the engine knock

Cooling that air down now there is more molecules to same volume thus better charge to cylinder, hence reduce knock, raise octane %
MAT reports less heat, PCM is happy and not yanking spark so more torque.

Also again GM concerned about hot air so MAT is feedback sensor to trigger when the inner cooler coolant pump is commanded on/off
So GM is using MAT for boost control and not just IAT
 
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