NB Randall Cowl Intake V2
NB Randall Cowl Intake V2
Exclusive to Flyin' Miata!
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Description
There are lots of intakes out there, but most of them make more noise than power. If you have an open air filter under the hood, especially if you don't have a heat shield, it's going to suck in hot air. Even a heat shield won't help much if it isn't fully enclosed. Hot air is less dense - i.e., it has less oxygen - so it's going to make less power. That open air filter is great for making noise, which can make the car feel stronger, but if it's sucking in hot air it's probably making less power than the stock intake. But what if they have dyno results?! Was that dyno testing done with the hood closed? If not, it's not a valid test.
We solved this problem a long time ago with our Randall cowl induction intake. It reuses the stock intake and air box for simplicity and economy (the stock parts flow great for the power levels here), but it makes it so the air comes from the base of the windshield. The benefit is twofold. First, it sucks in truly cold air, from outside of the engine bay. Second, it's force-fed - the base of the windshield is a high-pressure area, so more speed = more air forced into the engine. This results in a dyno-proven - with the hood closed! - 5 hp, as measured at the wheels. It also adds a bit of intake growl, although it's more subtle than an open filter.
The Randall has been gone for a while - our original supplier retired - but we've brought it back better than ever. It's now silicone, which makes the install dramatically easier than the old rigid tube. It's also about half the price! It's more durable, and we now have a firewall plate to secure the end of the hose. The firewall plate also eases installation (it's ridiculously easy to locate the hole), visually cleans things up, secures your clutch line, and has a simple (and unintrusive, flow-wise) screen to keep the intake from sucking up leaves in the cowl.
Installation involves cutting a hole in the flange at the top of your firewall (the firewall plate is your template, so it's pretty easy). This may not be allowed in some race classes, so do your homework. 1 3/8" (35mm) hole saw required, not included.
CARB approved (D-601-5) so it's fully legal everywhere in the US. Since it's pre-airbox, it's likely legal everywhere, but check your local rules to be sure.
Fits all NBs with left-hand drive, with no issues with cruise control or shock tower braces, though the cruise control actuator will have to be relocated slightly. Sorry, it doesn't fit with right-hand drive.
Note that if you use this with a cowl washer bottle, like what we sell, the parts will physically fit, but the washer bottle will sit very close to the mouth of the intake. Check out the dyno chart - on our car installing the cowl washer bottle meant the car picked up about 3 hp instead of 5 - so still beneficial over the stock intake, but not as beneficial as the Randall with no obstructions.
Photos shown are sample product. Final production items may vary slightly from what is shown.
Instructions
Shipping
What does it fit?
Fits: 1999, 2000, 2001, 2002, 2003, 2004, 2005
Emissions
50 state legal!
CARB EO: D-601-5
Warranty
1 year
SKU
Pros: On a MSM with a stock intake and drop in filter, it helps eliminate heat soak by drawing colder air from the cowl and maintain the power. Sound from the turbo spooling and the bypass valve are more pronounced and I can feel a noticeable gain in power. Butt dyno approved!
Cons: Cutting through the firewall.
This is a really good alternative to a regular cold air intake. I wish the cruse control relocation was a little better but works just fine. I did have a little problem with the clip that holds the metal line in place but the customer service was amazing and was resolved extremely fast. Will recommend everyone to shop at flyin Miata
Installation is a breeze with the right tools. Adds a really nice intake growl when engine is under load. Did not officially Dyno. However, butt dyno confirms a significant bump in pep, especially at the lower end of rev range. There aren’t many bolts that add any noticeable increase. This is one of them!
The instructions are clear and installation is easy with the recommended tools. Works as designed. The only thing I would change is, I would add something in the instructions saying you should touch up the exposed metal from the cut using some touch up paint.
Hi Dean, we're glad to hear that you're enjoying your Randall Cowl Intake Duct! We do mention cleaning up the newly-cut edges and using touch-up paint to cover the bare metal in step 9 of our installation instructions, but it looks like you've already taken care of that for your install, too! Thanks again!
I have made several DIY versions of this intake over the years. I even did my own testing back in graduate school to confirm the temperature differences between stock and this approach. This upgraded FM version was super easy to install and has great build quality. It's not a huge gain, but the car does breathe a bit easier now. And I can confirm the physics of the approach. Plus the growl from under the hood is fun.