Instead of talking about the merits or shortcomings of the R2C kit over other intakes, I thought it might add value to share some observations about fitment and parts. Since getting the intake last month, I've been playing with the setup, trying to get to a happy place. I must have removed and adjusted these things at least a dozen times now.

Anyway, that's the thread intent. Feel free to contribute.

Here's the kit in Black Nickle. That finish is a hefty premium over polished aluminum or simple, gloss black, but man-oh-man, is it worth it. So pretty.



And here it is installed.

 

There’s a tubular rubber molding around the edges of the heat shields. On the driver’s side it goes all the way around and is fairly secure. But on the passenger side, there’s a cut-out in the heat shield to compensate for the radiator hose. At this point, the rubber molding just ends. Anyway, it won’t hold, and almost right away, about 4” will just be flopping there loose.

You have to secure the wrap-around molding. So drill a hole through it, and use a nut, washers and bolt cut to length. Because the rubber is in the middle, you can tighten it secure enough not to worry about backing out. Or you could use a nyloc nut.

Then mask the surrounding area on both sides, and spot-spray the nut & bolt hardware with flat or satin black.

 

The retaining brackets are supposed to connect to the OEM airbox brackets, which themselves are bolted to the fenders with standard M6 bolts. However, the hardware that R2C gives you to attach the heat shield to their bracket just isn't good enough. You're going to want to use a larger washer on the inner side to spread out the contact point, preferably a rubber-backed washer. I really like those little things; SS on one side, and rubber on the other. And use a nyloc nut. Believe me that you’re going to want to use a nyloc nut here.

This is important, so I'll repeat that: use a nyloc nut.



Like the heat-shields, it looks like the R2C brackets were painted with a textured satin black, but without any primer. WTF? It’s nuts how easily they scratch.

Strip the paint off the brackets easily with a wire-wheel, then prime and paint. While at it, you can do the same for the OEM airbox brackets, and the similar bracket that holds the door-chime. They’re all just raw, galvanized steel. When painting these, I went with satin-black and a clear-coat finish. My rattle-can skills are lame, but from more than a few inches away, it looks OK enough.

BTW, if you need to bend the R2C brackets to fit, you’ll probably want to get that configured however you want it, before painting.

Suppose you could paint the heat-shields, too, although that’s a whole lot more work.

 

With heat and vibration, over time the filter elements will slip off the mid-pipe. They just will, and it’s very frustrating. The filters are actually tilted at a light downward angle, and the mid-pipe is all slippery smooth. At least, the Black Nickle finish is.

So all you need to do is rough-up the finish on the neck of the mid-pipe. Some high-grit sand-paper, and you’re good to go. The filters will stay on nice and secure, without having to constantly tweak the compression on the clamps.

And the clamps around the filter neck... if you orient the clamp screw facing upwards on one side or the other of the filter, then you’ll have easy, repeatable access to removing the filter.

 

The kit comes with 6, stainless-steel worm-clamps. I went and bought four, far more substantial, stainless-steel T-bolt clamps for the throttle-body couplers. (Seen here.) But there was no orientation that I liked. If the hardware were on the down-side, then it could rub against the coolant hoses. And if the hardware on the top-side, it looked too mechanical and busy. You can’t orient the hardware to the rear, because the TB housing gets in the way. So the only place to put it is oriented vertically on the front-side… and you end up with the T-bolts sticking straight up in the air. Plus, the SS bands themselves are too thick on the T-Bolts, and together cover 90% of the coupler.

Long story short, just use the worm-clamps. You can orient the hardware towards the bottom, and it will look clean. Plus, there’s just enough clearance.

If you don't like the shiny stainless-steel, Sure Motorsports sells a product they call "Stealth Clamps", which are simply good quality worm-clamps with a black coat of something. I considered getting four... and am still considering it. Here's the link: Stealth Clamps? | SURE Motorsports Mazda Performance Equipment

Here's a picture of a HPS coupler (that I did use) with the T-bolt clamps (that I didn't actually use), next to the R2C coupler (which I also didn't use) with worm clamps (that I did use.)

 

The couplers RC2 gives you are sturdy, and branded R2C, like in the previous picture. If you don’t like the branding, just mount them towards the back or bottom. However, if you don’t like the color, you need to replace them. HPS makes high quality couplers, in a variety of colors with a glossy surface; (I went with black). The interesting thing about HPS is the interior/edge has this amber color that you can see as a ring around the mid-pipe. It’s really attractive.

You need two 70mm couplers, each 2" long. But good luck finding that in 2” length. However, for $20, you can buy a 4” HPS coupler, and simply cut it in half. When installing, orient the cut edge towards the throttle-body, because no matter how steady you are with the box cutter, it just won’t look as clean as the machine-cut edge.

 

Don’t bother with the extension of hose that comes with the kit. It’s pretty much useless.

The driver’s side isn’t a problem… it’s the passenger side that’s a PITA. What I ended up doing is cutting a 1/2" off the valve-cover end, and slipping it under the fuel-line. The downside is the slight contact point between the breather hose and the fuel line... although I suspect in that fight, the fuel line rubber will win out over the softer breather hose. Time will tell. Keep an eye on it and figure something out as needed.

 

The R2C kit creates a really nice sound, but it’s muffled by the hood liner. Also, if you mount the heat shields too high in the engine bay, they could be crushed against the hood liner. Fortunately, there’s a simple solution.

Remove the hood liner.

 

Does the R2C intake has different model # for 07-08 G35 sedan and 09+ G37 sedan?

I have K&N SRI and they have different model # for G35 and G37 sedans. The reason I found out is, the breather hoses are different on both the driver and passenger side.

This might contribute to the passenger side breather hose you are describing.

 

IDK. That's certainly possible. Another explanation is that aftermarket mods often require customization and compromises.

Whatever comes, I detail the engine bay often, so I'll be sure to keep an eye on the wear between the contacts in the rubber, if any.

 

Can you just put a little dab of rubber-friendly lube between them like RRG? Might not do much more than prevent worry, but there is that.

 

Great write up John, super reference for those folks thinking about getting the R2C or those that want to improve on the original setup. Too bad you had several issues but you're just the person to tackle it head on and make improvements throughout the system.

My Injen SRI also had a couple issues that I had to deal with to make the install more trouble-free. From what I've read, almost every intake it seems that it's up to the owner to really "finish" the system.
I prefer the look and design of the Amsoil filters though, seem to allow better flow w/ their open horn design and also look to be a bit bigger (plus I like the blue color, lol). But can't argue about the overall look of the R2Cs, especailly that black nickle finish, just a beautiful addition to your stellar engine bay

 

I had to look that up. RRG = Red Rubber Grease. Apparently any silicone grease would work in this case as well.

Good advice, brizey!

 

Nice work. Send this thread to r2c so they can work out these issues.

 

I was looking at this intake so in your opinion is it worth getting or should I go with the overprice Stillen?