rpi
1 - 20 of 21 Posts
Joined
·
1,192 Posts
Best to buy direct from RPi: RPi - Race Precision, Inc.
Ajax doubts that ram air scoops will make your car run cooler. Well, it will be cooler, just not cooler. Check under the hood for a dead cat or other animal. That can cause an odor problem which will take that "smile" off your face but quick!
.
Ajax doubts that ram air scoops will make your car run cooler. Well, it will be cooler, just not cooler. Check under the hood for a dead cat or other animal. That can cause an odor problem which will take that "smile" off your face but quick!
.
Attachments
Joined
·
4,512 Posts
Looks like Fluffy picked the wrong place to take a nap!
OP - yes my car has a slight temporary odor if it has just been driven hard. I just figured it was tires or brakes...
And naturally after driving hard, the fan up front runs after the car has been turned off. And the floating brake rotors "creak" for a while as the discs contract concentrically on the radial locating hub pins. But those are sounds, not smells.
The RPi scoops should help your engine to get cool air when driving a speed. And the effect of engine heat soak should be reduced compared to some aftermarket "cold air" systems that do not isolate the air intake from the under hood air. These are really "hot air" systems! The factory system is pretty well sealed but the RPi scoops will get more cold air to the filter based on how fast you are driving.
OP - yes my car has a slight temporary odor if it has just been driven hard. I just figured it was tires or brakes...
And naturally after driving hard, the fan up front runs after the car has been turned off. And the floating brake rotors "creak" for a while as the discs contract concentrically on the radial locating hub pins. But those are sounds, not smells.
The RPi scoops should help your engine to get cool air when driving a speed. And the effect of engine heat soak should be reduced compared to some aftermarket "cold air" systems that do not isolate the air intake from the under hood air. These are really "hot air" systems! The factory system is pretty well sealed but the RPi scoops will get more cold air to the filter based on how fast you are driving.
Joined
·
4,512 Posts
Is that the "Pussy Wagon" Uma Thurman drove in "Kill Bill"?
Joined
·
7,038 Posts
Wirelessly posted (Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_2_1 like Mac OS X; en-us) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8C148 Safari/6533.18.5)
If I were you I shall go for the RPI Oil Cooler.
I have RPI scoops for a while now and am beggininh to doubt the effectiveness of scoops.kubi510 said:
If I were you I shall go for the RPI Oil Cooler.
Joined
·
4,512 Posts
Drive faster my friend! :wroom::M5launch:
Joined
·
7,038 Posts
That is the point.
If we have scoops with block off plates, as we drive faster the air box is pressurised and creates a high pressure area inside the air box. However, the air mass sensors shall only take the air they need and block the rest.
This would imply that there is a high pressure area inside the air box and a low pressure area near the soops. Thus, the scoops shall not be able to force more air into the air box.
Just my 2 cents. I might be terribly wrong.
Joined
·
4,512 Posts
I don't think so. The forward motion of the car create greater than normal atmospheric pressure at the scoops while the air box (before the filter) would without any ram effect would only have atmospheric pressure (at best). I'll let the RPi guys chime in here (again).
Joined
·
7,038 Posts
Indeed!
But the DME controls the throttle bodies and inlet pressure valves based on the readings provided by the MAF Sensors.
Therefore, it does control the air flow, indirectly.
Joined
·
7,038 Posts
Indeed! The pressure shall be greater at the scoops, but once the air box is pressurised (before the filter) the scoops shall not be able to do anything, as the air flow in the engine through the filter is restricted.
Therefore, the scoops shall only be effective until the air box is not pressurised.
Its like blowing a piece of paper in a bottle, it shall not go in if the pressure inside the bottle is equal to or greater than the pressure outside the bottle.
Joined
·
4,512 Posts
Not a good analogy I think because the engine drawing in air creates a partial vacuum (in a non-FI system).
Joined
·
7,038 Posts
Exactly my point.
If the engine is drawind in air because of the vaccume created by the combustion process, the scoops are rather ineffective.
In this case, the air flowing in through the intake without the scoops would also be more than sufficient for the purpose.
Its not like the air is being forced into the system, it is being drawn in.
Joined
·
4,512 Posts
Never mind
Joined
·
7,038 Posts
Wirelessly posted (Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_2_1 like Mac OS X; en-us) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8C148 Safari/6533.18.5)
LOL
Think about it Sir. Perhaps it shall make sense after some time.
Or it might be absolute BS, which is quite likely.
LOL
Think about it Sir. Perhaps it shall make sense after some time.
Or it might be absolute BS, which is quite likely.
Joined
·
3,394 Posts
The only time the throttle body butterflies are shut is when the throttle is completely released (short of the minimum opening necessary for idle), at which point you don't need any extra air.
The ECU adjusts the amount of fuel supplied to the injectors according to what the MAF sees.
The engine is basically an air pump, and a rather inefficient one. As long as you have sufficient fuel delivery, the more air you can provide and/or force through it, the more power you will have. This is why restrictor plates work to limit power.
The only way the MAF can impede physical airflow is if the amount of air the engine is trying to ingest exceeds the maximum CFM of air that can pass through the MAF. In other words, the MAF becomes a bottleneck, like when a person tries to breathe through a straw. I've only ever heard of that happening in forced induction applications. Never when naturally aspirated.
The other way the MAF can act as a restriction is if the sensor hits its maximum voltage, meaning the amount of air passing through the sensor exceeds the maximum amount of air it's calibrated to measure. This is also known to happen in forced induction applications. But that isn't a physical blockage of airflow, it's simply maxed out and unable to provide any higher readings to the DME.
The theory behind the scoops is that they help provide a "ram air" effect. I am in no way, shape or form knowledgeable in fluid dynamics, but I've seen ram air setups provide quantifiable benefits on different cars many times.
Reading about Bernoulli's principle gives me a headache, but it's worth reading. http://en.wikipedia.org/wiki/Bernoulli's_principle
The other way the MAF can act as a restriction is if the sensor hits its maximum voltage, meaning the amount of air passing through the sensor exceeds the maximum amount of air it's calibrated to measure. This is also known to happen in forced induction applications. But that isn't a physical blockage of airflow, it's simply maxed out and unable to provide any higher readings to the DME.
The theory behind the scoops is that they help provide a "ram air" effect. I am in no way, shape or form knowledgeable in fluid dynamics, but I've seen ram air setups provide quantifiable benefits on different cars many times.
Reading about Bernoulli's principle gives me a headache, but it's worth reading. http://en.wikipedia.org/wiki/Bernoulli's_principle
Joined
·
1,192 Posts
Cold air is much denser and holds more oxygen per volume than warm air. More oxygen molecules going in means a more efficient burn and more power in the combustion process. The result is more horsepower.
Ajax believes that any ram air system supplying cool air (especially with block off plates as in the M6) will provide considerably better perfornamce gains in climates where the ambient air temperature is on average lower, such the Pacific Northwest where he lives, vs. significantly higher average temperatures like the UAE where the daily average is hotter than a popcorn fart.
Ajax believes that any ram air system supplying cool air (especially with block off plates as in the M6) will provide considerably better perfornamce gains in climates where the ambient air temperature is on average lower, such the Pacific Northwest where he lives, vs. significantly higher average temperatures like the UAE where the daily average is hotter than a popcorn fart.
1 - 20 of 21 Posts
Join the discussion
