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I am looking to get a Cold Air Intake system installed and would like to get some thoughts and experiences out there with the different brands like K&N or AFE or Dinan. I like Dinan but its really expensive.

I am also wondering about those RPI airscoops and if that in itself is a different item meant to enhance stock intake systems and aftermarket CAI systems or just the former. Thanks
 

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I am looking to get a Cold Air Intake system installed and would like to get some thoughts and experiences out there with the different brands like K&N or AFE or Dinan. I like Dinan but its really expensive.

I am also wondering about those RPI airscoops and if that in itself is a different item meant to enhance stock intake systems and aftermarket CAI systems or just the former. Thanks
Hot air intake systems tend not to work unless you drive without your hood.

The RPi scoops are meant to be used in conjunction with the stock intake. They've been dyno'd over and over by us and by customers at their own chosen 3rd party dyno, and consistantly show substantial gains. While they were originally designed for the stock intake, they've been shown to increase power to the Dinan setup as well.

On our very conservative dyno, they've shown around a 15hp to the wheels gain given a 13k CFM fan approximating 70mph. Adding the blockoff plates will give you another 4-6hp, again on this conservative dyno. Swapping the stock paper filter to a BMC will give you gains on top of this, as will removing the stock charcoal filters.
 

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I have Dinan intake with RPI scoop. Dinan intake draws cold air from the bottom , they have tube running from bottom of the grill to the air box and if you put RPI scoop with it, it will direct more air to the air box. You know what they said, more air more power. Also I saw a post that, with RPI scoop and Dinan intake= more power.
 

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I have Dinan intake with RPI scoop. Dinan intake draws cold air from the bottom , they have tube running from bottom of the grill to the air box and if you put RPI scoop with it, it will direct more air to the air box. You know what they said, more air more power. Also I saw a post that, with RPI scoop and Dinan intake= more power.
You are aware that the stock system also draws air from the bottom right? The brake ducts serve for two purposes, to channel air to cool your breaks, and the other to put more air into your intake boxes. The problem however is the turbulence that is created from having air coming in from the ram intakes and also your brake ducts. That is exactly why RPI designed the block off plates to make sure that the air is coming from directly ahead.
 

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I do not suggest replacing your stock sealed OEM Air box with any open cone style intakes (such as K&N / AFE). These types of intake systems have repeatedly shown an overall power LOSS on both the dyno and real world situations. Although both the K&N/AFE utilize a partial heat shield enclosure, radiant heat from the engine bay with the hood closed will still make its way into the compartment where these cone filters draws air from.

I suggest simply retaining your OEM air box, getting scoops/blockoff plates and a drop in performance filter. The Dinan is very nice but has a hefty price tag. Look into the RPI Ram Air Induction Kit w/ blockoff plates or AFE's "OEM+" Super Stock System.

The only alternative I can suggest would be the ASR CAI. Although availability/price of this particular system is a concern.
 

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I just recently installed the RPI Scoops, block off plates and BMC filters, along with removing the Charcol filters then had to run my own speed test. I initially removed the charcol filters then tested and noticed a difference. A few days later the RPIs showed up with the BMC filters and installed them then test drove with heavy accelleration and again noticed a definate improvement in the throttle response and accelleration. It was a cheap mod that I'm very happy with, with a noticible difference.
 

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I just recently installed the RPI Scoops, block off plates and BMC filters, along with removing the Charcol filters then had to run my own speed test. I initially removed the charcol filters then tested and noticed a difference. A few days later the RPIs showed up with the BMC filters and installed them then test drove with heavy accelleration and again noticed a definate improvement in the throttle response and accelleration. It was a cheap mod that I'm very happy with, with a noticible difference.
Thinking of doing exactly what you did with the RPI Scoops, block off plates, BMC filters and removing the charcoal filters. Difficult job? Where are you in VA? I am located in Waldorf, MD....
 

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Thinking of doing exactly what you did with the RPI Scoops, block off plates, BMC filters and removing the charcoal filters. Difficult job? Where are you in VA? I am located in Waldorf, MD....
I live in Williamsburg. The charcol filters didn't want to release the clips so I ended up destroying them; but they were never going back anyways. Overall not too difficult, have to get the kidney grills removed for the scoops. Would be more than willing to give you a hand if you want to make the road trip.
 
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I live in Williamsburg. The charcol filters didn't want to release the clips so I ended up destroying them; but they were never going back anyways. Overall not too difficult, have to get the kidney grills removed for the scoops. Would be more than willing to give you a hand if you want to make the road trip.
Thanks for the offer and info, I appreciate it. Is there a link to RPI somewhere? I didn't see them in the sponsor list....
 

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Just ordered my RPI scoops, filters and block off plates....I will give a report on them after the install. It makes sense to me to stick with the stock intake boxes, the cold air intake will be taking warm air from the engine compartment. On most piston airplanes, this results in a 10% reduction in power when taking warm air from inside the engine compartment versus outside cold ram air. I am certain you can expect similar results with a cold air intake that does not block off the engine air.
 

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Take a look at this thread that I put together a few months back. i wanted to do some real life testing of the JAWS CAI and RPI scoops. Take a look at my real world results. Not just dyno numbers, but true 60-130 times.

Just as a side note all the tests were run in the winter so temps were cold so you may see different results in a hotter climate. Also, my 60-130 times are a little slow due to a lack of traction caused by the cold temps.

http://www.m5board.com/vbulletin/e6...cussion/215918-real-world-intake-testing.html
 

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All I gotta say is I notice a difference in power with Dinan's intake and RPi scoops. My MPG also went up by about 1 in the city and like 3 on the highway.
 
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