CAI Hydro-Shield

[Wangtang408]

Anybody out there using Hydro-shield with their CAI? Are they any good?

[DeanM45]

Took mine off and threw it in the trash. Then again, I am in California so not much rain. I think it served more as a pre-filter to keep the actual filter a bit cleaner for longer. I get the theory behind them but you would have to submerge the filter in water and be at full vacuum for a while for enough water to come up and do any damage. Think about how hard (relatively speaking) it is to suck water up through a straw, now try that with a 3" diameter straw. Water weighs about 8lbs a gallon, and 1/8th of that, or a pint, assuming there is enough surface tension in the water, would still have to "lift" one pound of water up. I'm sure there are people that will say that they hydro locked a motor with an open element air filter but I have never seen one. Water injection is still a fairly popular power adder BTW.

[Wangtang408]

We don't get much up here in Norcal, we just got 1 day of rain last week and when it rains, it pours!!!
We get some huge puddles and couple floods due to some messed up roads (earthquakes). I ordered the Hydro-shield and should receive it today. Just to be on the safer side..

[svard75]

NA Engines produce almost 15psi at the intake. Based on a flow rate calculator using a 3" diameter by 1 meter long pipe the flow rate is 89.57 ft/s for water. I would say that in one second you could suck in enough water to stall the car and have trouble restarting.

Water injection only works if the ECU is tuned lean otherwise it does the opposite. Our cars are normally tuned to be rich to produce the same results as Water injection but at a higher cost.

I do agree that the likely hood of your intake being completely submerged is very low. It has happened to me where the car stalled. It did restart again without too much trouble but was idling badly and the black smoke! crazy.

Do you have the CAI where the filter is in the wheel well? Personally I despise those CAI's because first of all it's a PITA to get to when you need to clean the filter and second it's so low to the ground it's risky.

I have never seen real evidence that a CAI vs the OEM intake with a clean new OEM filter would make a difference in power. In fact those cheaper solutions that put the filter in the engine area create a negative effect robbing power. I have personally experienced the differences between RAM air intakes and any other CAI and that makes a difference although the filter usually becomes very dirty very quickly. There is also a major weight savings between the two systems.

[DeanM45]

NA Engines produce almost 15psi at the intake. Based on a flow rate calculator using a 3" diameter by 1 meter long pipe the flow rate is 89.57 ft/s for water. I would say that in one second you could suck in enough water to stall the car and have trouble restarting.

Water injection only works if the ECU is tuned lean otherwise it does the opposite. Our cars are normally tuned to be rich to produce the same results as Water injection but at a higher cost.

I do agree that the likely hood of your intake being completely submerged is very low. It has happened to me where the car stalled. It did restart again without too much trouble but was idling badly and the black smoke! crazy.

Do you have the CAI where the filter is in the wheel well? Personally I despise those CAI's because first of all it's a PITA to get to when you need to clean the filter and second it's so low to the ground it's risky.

I have never seen real evidence that a CAI vs the OEM intake with a clean new OEM filter would make a difference in power. In fact those cheaper solutions that put the filter in the engine area create a negative effect robbing power. I have personally experienced the differences between RAM air intakes and any other CAI and that makes a difference although the filter usually becomes very dirty very quickly. There is also a major weight savings between the two systems.

No, water injection is not for "lean tuned" cars. It is to reduce the intake charge temperature which is why it is most often used on forced induction cars. Show me ANY automotive engine that does not provide additional power with a colder intake charge.

Not 15psi at the intake, 15 inches of vacuum and sometimes, when decelerating, as much as 22 inches of vacuum. You can not use pressure (psi) instead of vacuum in the flow rate calculator. Besides, the engine has 15" of vacuum after the throttle plate--not in the intake tube. IF the tube were completely submerged then the vacuum would propagate into the intake pipe. The engine would stall with the absence of air (if the pipe were to "fill up" with water. This is why you had all the black smoke when restarting - fuel had puddled in the absence of combustion. Yes, adding a CAI without any other changes will not give you much additional power over the stock system. However, if you are tuned to utilize the additional airflow that is a completely different ballgame. And yes, I performed tests with the stock system and the Injen CAI taking vacuum readings before and after the filters, after the MAF and at the throttle body opening. The stock system DOES have higher vacuum and resistance to airflow compared to the Injen (and I will soon be testing a R2C). This means more airflow BUT to fully realize the gains you must richen up the fuel map (from about 2/3 throttle and up - the M45s run actually very LEAN from the factory).

All of my posts are from personal experience from building and racing cars for over 20 years, however, your mileage may vary, lol.

[Wangtang408]

The filter (cone) is actually behind the lower grill, per instructions supposed to remove to front bumper to install, but I ended pushing the filter down, I may have to remove the front bumper to clean the filter. The hydro shield also protects the filter from debris which should keep it a little cleaner. Thanks guys, your knowledge and sugggestions always appreciated

[elwesso]

first of all it's a PITA to get to when you need to clean the filter and second it's so low to the ground it's risky.

I have never seen real evidence that a CAI vs the OEM intake with a clean new OEM filter would make a difference in power. In fact those cheaper solutions that put the filter in the engine area create a negative effect robbing power.

This!!!

Overall those cone filters do more harm than good. Remember it takes about 15-20HP to even feel any noticeable difference, so if anything claims anything under 15HP that's almost unnoticeable.. Bigger fish to fry. Lots of work for almost no gain. Heck you can have that much swing based on temperature.

Don't think of an engine as "sucking" the air in, think of it as the atmosphere "pushing" the air in.. As the piston goes down, it increases the volume of the cylinder, thereby lowering the pressure, which causes the atmosphere to "force" air into the cylinder.

At 30°C (86 °F), dry air has a density of 1.16 kg/m^3. At 0°C (32°F), dry air has a density of 1.29 kg/m^3.. So that means for a 30°C swing in temperature, we've increased the density about 11%, which means that 11% more air is going into the engine, which means the engine can burn 11% more fuel, which theoretically means the engine is making 11% more HP. Assuming at the higher temperature you're putting out 300HP, at the lower temperature you'll be putting out 330HP, or a 30HP increase.

I'm sure everyone notices that their car pulls stronger in the winter time when it's cooler. My point is not to debate the actual numbers here, but to point out that 10HP in the grand scheme of things is pretty insignificant, so to waste time and money on these cold air intake deals is pretty pointless, IMO.

Also, if you assume that it's flowing more air, where does that decrease in restriction come from? That's right, it doesn't filter as many particles as well, so it will let more dirt into the engine which will wear it out faster, and make your oil dirty faster.

[svard75]

NA Engines produce almost 15psi at the intake. Based on a flow rate calculator using a 3" diameter by 1 meter long pipe the flow rate is 89.57 ft/s for water. I would say that in one second you could suck in enough water to stall the car and have trouble restarting.

Water injection only works if the ECU is tuned lean otherwise it does the opposite. Our cars are normally tuned to be rich to produce the same results as Water injection but at a higher cost.

I do agree that the likely hood of your intake being completely submerged is very low. It has happened to me where the car stalled. It did restart again without too much trouble but was idling badly and the black smoke! crazy.

Do you have the CAI where the filter is in the wheel well? Personally I despise those CAI's because first of all it's a PITA to get to when you need to clean the filter and second it's so low to the ground it's risky.

I have never seen real evidence that a CAI vs the OEM intake with a clean new OEM filter would make a difference in power. In fact those cheaper solutions that put the filter in the engine area create a negative effect robbing power. I have personally experienced the differences between RAM air intakes and any other CAI and that makes a difference although the filter usually becomes very dirty very quickly. There is also a major weight savings between the two systems.

No, water injection is not for "lean tuned" cars. It is to reduce the intake charge temperature which is why it is most often used on forced induction cars. Show me ANY automotive engine that does not provide additional power with a colder intake charge.

Not 15psi at the intake, 15 inches of vacuum and sometimes, when decelerating, as much as 22 inches of vacuum. You can not use pressure (psi) instead of vacuum in the flow rate calculator. Besides, the engine has 15" of vacuum after the throttle plate--not in the intake tube. IF the tube were completely submerged then the vacuum would propagate into the intake pipe. The engine would stall with the absence of air (if the pipe were to "fill up" with water. This is why you had all the black smoke when restarting - fuel had puddled in the absence of combustion. Yes, adding a CAI without any other changes will not give you much additional power over the stock system. However, if you are tuned to utilize the additional airflow that is a completely different ballgame. And yes, I performed tests with the stock system and the Injen CAI taking vacuum readings before and after the filters, after the MAF and at the throttle body opening. The stock system DOES have higher vacuum and resistance to airflow compared to the Injen (and I will soon be testing a R2C). This means more airflow BUT to fully realize the gains you must richen up the fuel map (from about 2/3 throttle and up - the M45s run actually very LEAN from the factory).

All of my posts are from personal experience from building and racing cars for over 20 years, however, your mileage may vary, lol.

Interestingly the wiki on water injection suggested that water injection was introduced to keep the combustion chambers cool but with a mixture of 50/50 Methanol/Water. It also stated that the ECU had to be reprogrammed to bring the mixture back to stoic. But anyway forget about water injection we're totally derailing this thread lol.

What you're saying makes sense about requiring an ECU to take advantage of the CAI. I've seen numerous videos of real world tests without ECU reprogramming and that's what I based my opinion on. I still hate them due to the placement of the filter though. I mean get a hood with a functional scoop and ram air system sure, but having to get dirty to change or clean your air filter? Not my taste any more.

[DeanM45]

first of all it's a PITA to get to when you need to clean the filter and second it's so low to the ground it's risky.

I have never seen real evidence that a CAI vs the OEM intake with a clean new OEM filter would make a difference in power. In fact those cheaper solutions that put the filter in the engine area create a negative effect robbing power.

This!!!

Overall those cone filters do more harm than good. Remember it takes about 15-20HP to even feel any noticeable difference, so if anything claims anything under 15HP that's almost unnoticeable.. Bigger fish to fry. Lots of work for almost no gain. Heck you can have that much swing based on temperature.

Don't think of an engine as "sucking" the air in, think of it as the atmosphere "pushing" the air in.. As the piston goes down, it increases the volume of the cylinder, thereby lowering the pressure, which causes the atmosphere to "force" air into the cylinder.

At 30°C (86 °F), dry air has a density of 1.16 kg/m^3. At 0°C (32°F), dry air has a density of 1.29 kg/m^3.. So that means for a 30°C swing in temperature, we've increased the density about 11%, which means that 11% more air is going into the engine, which means the engine can burn 11% more fuel, which theoretically means the engine is making 11% more HP. Assuming at the higher temperature you're putting out 300HP, at the lower temperature you'll be putting out 330HP, or a 30HP increase.

I'm sure everyone notices that their car pulls stronger in the winter time when it's cooler. My point is not to debate the actual numbers here, but to point out that 10HP in the grand scheme of things is pretty insignificant, so to waste time and money on these cold air intake deals is pretty pointless, IMO.

Also, if you assume that it's flowing more air, where does that decrease in restriction come from? That's right, it doesn't filter as many particles as well, so it will let more dirt into the engine which will wear it out faster, and make your oil dirty faster.

The filter is not the only factor in determining intake path resistance. Overall diameter of the system, number of turns, etc. Most of tests done by Bob's Oil Guy on dry flow filters against paper filters show that the dry flow filter more effectively and has less flow restriction (surface area of the filter medium plays a big part in this as well). Any restriction in the intake system, no matter how minute, will decrease the amount of air allowed to flow into the motor. Dirty or small filter, bends in the intake tube, changes in diameter of the intake tube, etc. all restrict airflow. Plus after I buy an intake system for my cars I never buy (or throw into land fills) an air filter again.