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Plenum vs. CAI

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Old 01-24-2006, 12:03 PM
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Plenum vs. CAI

Hey Gang,

I'm looking at my next mod and am considering one of these two:

1. Motordyne 5/16" ISO-thermal plenum spacer

2. Stillen CAI + Z-tube

My take is that the plenum would give me more performance, while the CAI/tube would sound better. Am I right?

Also, I want to go forced induction next year and want to make sure the plenum spacer is a good idea for a turbo or supercharged system.

Thanks in advance!
B
 
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Old 01-24-2006, 12:11 PM
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If I were you save up and do them all at once...either that or just get the spacer and ztube at least...and yes the spacer will be ideal for FI.
 
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Old 01-24-2006, 12:16 PM
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just get a plenum, z-tube, and k&n drop in filter...btw i have a crawford cast plenum for sale cheap if you want one
 
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Old 01-24-2006, 12:22 PM
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Crawford vs. Motordyne

What's the difference between Crawford/Motordyne? I've seen Motordyne's site and heard people rave about them. I know little about Crawford...

-B
 
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Old 01-24-2006, 05:03 PM
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Bang for your buck! Go with the motordyne plenum spacer first. Easy install and great gains
 
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Old 01-24-2006, 05:05 PM
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I have both.
I got my INJEN CAI first...and then I got the Motordyne Iso Thermal.
The motordyne really enhances the intake sound...makes the engine deeper and throatier sounding (or it in my head) regardless.
I say do them both.
I really didn't notic any power gains from the intake just sound (but sounds amazing).
Definitely noticed power gains from the motordyne though.
 
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Old 01-24-2006, 05:39 PM
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motordyne is a spacer and crawford is a replacement plenum...and mine was used for 3k miles and is cheap
 
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Old 01-24-2006, 06:14 PM
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Plenum vs. plenum spacer

Okay, I think I'll get the CAI AND the spacer. Why would a Crawford plenum be better than the OEM plenum though? And how much you asking for the Craw plen?

Thanks
b
 
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Old 01-24-2006, 06:31 PM
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Originally Posted by shdowflare
Okay, I think I'll get the CAI AND the spacer. Why would a Crawford plenum be better than the OEM plenum though? And how much you asking for the Craw plen?

Thanks
b
You may want to search more on this forum, and you can read about what a spacer does (vs. no spacer) and what an aftermarket plenum does (vs. OEM one). I do hope that you've at least read what the spacer actually DOES for your car & for performance, as you're about to buy one....either way, here's the your answer in a nutshell: Oem plenum is at a set depth/height off of your engine, allowing only so much air to pass from your intake into your engine....also, from what I believe I've read on this forum, the height/depth is smaller @ the front of the car, thereby allowing less air to the two front cylinders. A 5/16" plenum spacer increases OEM height by 5/16"; thereby allowing more air volume to pass thru. An aftermarket plenum is "taller" (heights vary), thereby allowing more air to pass thru (hence the APS "Tall boy" plenum spacer name also which can be found on this forum). Hope that answers your questions. PS - I also think people have used spacers with aftermarket plenums for bigger gains, but I don't believe you can't use the plastic engine cover with an aftermarket plenum. Happy moddying!
 
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Old 01-24-2006, 06:33 PM
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Plenumism

Okay, so I read up and found out why an aftermarket plenum is a good thing. What I'm wondering is if you can still fit the engine cover on the car if you get the Crawford (or any other) plenum? Or is the engine cover only usable if you put on the 5/8" plenum spacer on the OEM plenum?

Thanks again....

-B
 
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Old 01-24-2006, 06:49 PM
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I don't think you can, but you could always call them & ask, if nobody gives you an answer here. Not only do you have to worry about height issues, but the plenum woud have to have the bolts on them, in order for the plastic cover to be placed back on.......
 
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Old 01-24-2006, 06:54 PM
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you cannot put the oem engine cover on top of the crawford plenum
 
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Old 01-24-2006, 07:00 PM
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the crawford does the same thing as a spacer but is one unit...
 
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Old 01-26-2006, 02:12 PM
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Gotcha

Thanks for the help. I'll stick with the spacer. I like the engine cover, not too hot on the look of the Crawford plenum.

One more thought on this topic: does anyone know if Motordyne is the only spacer to consider or should look at some others, such as Skunk2, etc?

Thanks again
B
 


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