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DIY Stock Intake Mod

39859 Views 90 Replies 34 Participants Last post by  foreverkidd
Hi Guys,

Well, I got to thinking about the stock dual stage intake and figuring out a way to keep fender side intake opening open all the time. In case you didn't know, the fender side intake opening is closed until around 3600rpm, which is when it opens up, thus resulting in the now infamous and much beloved "IS-F Roar". As you can see from the picture below, all I did was just pull off the vacuum hose from the actuator and plug off the other end with a vacuum cap. Now the "IS-F Roar" comes on around the 2300rpm, and to me atleast, there seems to be a bit more power down low...which makes since because now the engine can breathe a bit better down low with both intake opening being open all the time. The only downside would be if this throws off the air/fuel ratio's from stock. I don't think it will drastically, but I'm not sure. Anyway, try it out and let me know what you guys think. Oh yeah, no check engine light either! Have fun...Darshana S...

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I want to try this out on my F.
What kind of vacuum cap does one get for this?
Thanks for the details Fig!

I did the mod tonight. First I took out the car (before doing the mod) and drove around slowly letting it warm up. I'm still not used to all the power, especially since I was also driving the is300 all day today.
Then I came back home and did the mod. At first I didn't really notice much.
I heard a bit of fluttering on the lower end. After driving the car on Sunset, from PCH to Hollywood I finally started to hear the difference. I put the car in sport mode and definitely noticed it feel a bit more pickup off the line. I also attributed this to the fact my fuel tank was on Empty. :)
I filled up the tank, kept it in sport mode, and yah, I do notice the difference.

I'll be keeping this mod on.
Are there any drawbacks to keeping this on? Higher fuel consumption? Additional wear on the engine? The former I'm not so concerned about, the latter a bit more.
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