new diy cold air intake
10-08-2013, 02:41 PM
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new diy cold air intake
hello i am new to the 8, but not to trying to rig up some diy stuff to go faster. well when i bought my 8 i think i have met my match. until the other day when i was researching the revi intake online. from what i can grasp it looks to me they are using a similar air box to stock just adding a cone filter inside and in a way to get the best flow. well i think i have came up with something for the diy that is in all of us.
1. remove walls
2. remove first (outer) screen
3. remove vfad tube
4 replace stock filter with kn drop in
now if someone could help with posting pics ill do tht right away. im on an iphone 4
1. remove walls
2. remove first (outer) screen
3. remove vfad tube
4 replace stock filter with kn drop in
now if someone could help with posting pics ill do tht right away. im on an iphone 4
10-08-2013, 03:03 PM
#3
and then get rid of the k/n drop in, because it is garbage and notorious for letting dust particles pass through.
and then take a look at your MAFv on idle to see how removing the first screen just made your v's spike intermittantly (just because the car seems to idle fine, doesn't mean the ECU isn't going bananas to compensate for the crazy MAF readings).
and then take a look at your MAFv on idle to see how removing the first screen just made your v's spike intermittantly (just because the car seems to idle fine, doesn't mean the ECU isn't going bananas to compensate for the crazy MAF readings).
10-08-2013, 03:35 PM
#4
hello i am new to the 8, but not to trying to rig up some diy stuff to go faster. well when i bought my 8 i think i have met my match. until the other day when i was researching the revi intake online. from what i can grasp it looks to me they are using a similar air box to stock just adding a cone filter inside and in a way to get the best flow. well i think i have came up with something for the diy that is in all of us.
1. remove walls
2. remove first (outer) screen
3. remove vfad tube
4 replace stock filter with kn drop in
now if someone could help with posting pics ill do tht right away. im on an iphone 4
1. remove walls
2. remove first (outer) screen
3. remove vfad tube
4 replace stock filter with kn drop in
now if someone could help with posting pics ill do tht right away. im on an iphone 4
10-09-2013, 10:44 AM
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and then get rid of the k/n drop in, because it is garbage and notorious for letting dust particles pass through. and then take a look at your MAFv on idle to see how removing the first screen just made your v's spike intermittantly (just because the car seems to idle fine, doesn't mean the ECU isn't going bananas to compensate for the crazy MAF readings).
what these MAFv u speak of
10-09-2013, 10:48 AM
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MAF = Mass Air Flow.
It's a sensor that detects how much air is flowing into the engine. It is very sensitive to air flow changes, and you can run into all sorts of problems if the airflow isn't hitting it correctly. CEL codes, power loss, stumbling, hesitation, etc... You need a certain distance of straight pipe before it, after it, and the screens to keep the air flow straight.
The OEM paper filter isn't a restriction to air flow, and neither are the screens. If you don't believe me, then believe the Grand-Am teams. They use the factory street RX-8 paper filter on the 450hp 3-rotor race cars. If it flows enough for them, it certainly flow enough for your 228-242hp street car.
It's a sensor that detects how much air is flowing into the engine. It is very sensitive to air flow changes, and you can run into all sorts of problems if the airflow isn't hitting it correctly. CEL codes, power loss, stumbling, hesitation, etc... You need a certain distance of straight pipe before it, after it, and the screens to keep the air flow straight.
The OEM paper filter isn't a restriction to air flow, and neither are the screens. If you don't believe me, then believe the Grand-Am teams. They use the factory street RX-8 paper filter on the 450hp 3-rotor race cars. If it flows enough for them, it certainly flow enough for your 228-242hp street car.
10-13-2013, 05:08 PM
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The facepalm is because 1 single number doesn't matter. Even if you plotted the actual engine ingested air flow against what your MAF is reading, you STILL can't compare it to other cars because the sensors differ from car to car.
You might be reading 1.22v, but what does that mean? is that 4.8g/s? is that 5.2g/s? is that 5.8g/s? is that 60g/s?
The voltage by itself is useless. Even the voltage and the RPM together is useless. Try the voltage at each RPM and each calculated load up against the MAF scaling values, the engine trimming values, the altitude, the ambient temperature, and the humidity.
It still doesn't change the basic intake principles that were provided to you above.
You might be reading 1.22v, but what does that mean? is that 4.8g/s? is that 5.2g/s? is that 5.8g/s? is that 60g/s?
The voltage by itself is useless. Even the voltage and the RPM together is useless. Try the voltage at each RPM and each calculated load up against the MAF scaling values, the engine trimming values, the altitude, the ambient temperature, and the humidity.
It still doesn't change the basic intake principles that were provided to you above.
10-14-2013, 03:39 PM
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idle is 9.68 g/s. 2500 is 18.14 g/s. 5000 and 8000 were same at 27.21 g/s. all im looking or is a yah or nah on numbers
amb temp 65 and in PA usa so little above avg altitude
amb temp 65 and in PA usa so little above avg altitude
Last edited by RIWWP; 10-14-2013 at 03:47 PM.
10-14-2013, 03:46 PM
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Did you read my post?
Here, I'll re-quote the key part:
I can give you 1 piece of information that would be useful though:
9.68g/s is CLEARLY a problem at idle, because the engine only uses about 5.5g/s. There is no valid reason your MAF should be reporting nearly double that, under ANY ambient condition while at idle. It's like someone posting a 600whp dyno of a stock 1991 Toyota Corolla. It simply isn't possible to be accurate.
Here, I'll re-quote the key part:
The voltage by itself is useless. Even the voltage and the RPM together is useless. Try the voltage at each RPM and each calculated load up against the MAF scaling values, the engine trimming values, the altitude, the ambient temperature, and the humidity.
9.68g/s is CLEARLY a problem at idle, because the engine only uses about 5.5g/s. There is no valid reason your MAF should be reporting nearly double that, under ANY ambient condition while at idle. It's like someone posting a 600whp dyno of a stock 1991 Toyota Corolla. It simply isn't possible to be accurate.
10-16-2013, 11:14 AM
#17
KN filters are over oiled from the factory.
Need to use air gun to blow all the excess oil off the filter.
Otherwise.... it will get on the MAF and screw with idle and performance.
Need to use air gun to blow all the excess oil off the filter.
Otherwise.... it will get on the MAF and screw with idle and performance.
10-16-2013, 03:19 PM
#18
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I hope you're doing this just for exploratory fun only.
There's not much to be had doing an intake mod.
The stock flows plenty enough for NA applications and removing the airbox assembly makes it buzzy and loud.
There's not much to be had doing an intake mod.
The stock flows plenty enough for NA applications and removing the airbox assembly makes it buzzy and loud.
01-25-2023, 06:25 AM
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09-21-2023, 10:44 PM
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hello, not sure if this is the right place to post but I will go ahead anyways. Long story short my rx8 goes into limp mode every time I start it up. Even at idle it is in limp mode. After some research I purchased an OMP from ebay and swapped out the old one and it is still in limp mode. However now it is throwing a code p0506. Not sure if it is MAF related or something to do with the new OMP. Any thought? Thanks
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