So I've had an R2C intake for a while now, been loving it but like most people who mod their car was always looking for the next thing to improve. I had a CAI on my last car and always wanted one for my Max. I got the idea to do this from Wally (ifuxwituz) but to be honest he wasn't much help (misled me with pipe lengths/angles) so I researched and measured and cut my own custom piping to fit.

I had to relocate the battery to the trunk, tried using a summit battery relocation kit which to be honest is a piece of junk. Just get a battery tray and some wires separately. Did some testing using a voltmeter before and after the relocation and critical parts of the car were reading 14.32 volts (car on) before relocation and 14.32 volts afterwards - money.

Then it took some trial and error and several trips to autozone/advance auto/pepboys but I eventually got the right piping to work off my old Takeda ram air intake and pipe it down next to the ECU and into the fender.

Now here's the most important part. The results. Keep in mind all tests had intermittent use of my lead foot so it's all even.

Stock Intake Test 1 - Temperature : 84 F, humidity 55%, 7:30 PM
Average AIT while not moving : 115 F
Average AIT while travelling ~50 : 98 F
Average MPG : 17.5
Average MPH : 21.5 MPH

R2C Intake Test 1 - Temperature : 105 F, humidity 60%
Average AIT while not moving : 167 F
Average AIT while travelling ~50 : 122 F
Average MPG : 16 MPG
Average MPH : 25 MPH

R2C Intake Test 2 - Temperature : 85 F, humidity 50%
Average AIT while not moving : 158 F
Average AIT while travelling ~50 : 121 F
Average MPG : 16.5 MPG
Average MPH : 26 MPH

Custom CAI Test 1 - Temperature : 80 F, humidity 50%, 2:00 PM
Average AIT while not moving : 123 F
Average AIT while travelling : 89 F
Average MPG : 22.4 MPG
Average MPH : 38 MPH

Custom CAI Test 2 - Temperature : 95 F, humidity 40%
Average AIT while not moving : 141 F
Average AIT while travelling ~50 : 113 F
Average MPG : 18 MPG
Average MPH : 22 MPH

Custom CAI Test 3 - Temperature : 80 F, humidity 60%, 8:30 PM
Average AIT while not moving : 109 F
Average AIT while travelling ~50 : 88 F
Average MPG : 19.5
Average MPH : 25 MPH

Custom Ceramic-coated CAI + CXJ BOP's Test 1 - Temperature 70 F, humidity 40%, 8:15 PM
Average AIT while not moving : 103 F
Average AIT while travelling ~50 : 82.5 F
Average MPG : 20
Average MPH : 29 MPH

Custom Ceramic-coated CAI + CXJ BOP's Test 2 - Temperature 77 F, humidity 30%, 6:30 PM
Average AIT while not moving : 104 F
Average AIT while travelling ~50 : 87 F
Average MPG : 16 (lead foot...been testing it kinda hard)
Average MPH : 26 MPH

Custom Ceramic-coated CAI + CXJ BOP's Test 3 - Temperature 70 F, humidity 50%, 7:00 PM
Average AIT while not moving : 106 F
Maximum AIT while not moving : 110 F
Average AIT while travelling ~50 : 77 F
Average MPG : 17 (again, lots of HEAVY driving, will do MPG tests later these are stress temperature tests)
Average MPH : 28 MPH

Custom Ceramic-coated CAI + CXJ BOP's + CXJ Thermal Spacers Test 1 - Temperature 34 F, humidity 30%, 7:30 AM
Average AIT while not moving : 54 F
Maximum AIT while not moving : 56 F
Average AIT while travelling ~50 : 44 F
Average MPG : 21
Average MPH : 32

Conclusion : When the pipes are cold you'll see a significant improvement in mileage. When they're hot it's not as great of an improvement, so having them ceramic-coated helps stabilize those temps a bit. It sucks the hot weather is gone, but I'll update with testing next time it hits 80 for a good side by side comparison. This thing just SCREAMS at high RPMs and I feel more power than my SRI used to give definitely, it also seems more even across the powerband which is great too. I was happy before, but now I freakin' love this thing. Throttle response definitely feels improved all around, I am VERY satisfied with this! If you have some time/spare cash (or just like working on cars) and want to improve power and mileage go for a CAI! This CVT just loves the colder air.

9/1/11 Update : Ambient temperatures still seem to be affecting the CAI a lot especially with it gets blazing hot outside. Still running better than the SRI but not by as huge margins as I was hoping. The pipes are currently off my car and getting ceramic coating/internal thermal barrier so we'll see how that helps control temps when idling.

9/24/11 Update : Finally got the pipes back, the place I took them too was mad busy but the wait was worth it. Temps are much more stable and only gradually increase compared to before where they just rose quickly to the engine bay temp when not moving. This thing plus the BOP's is great, it's like they were meant to be together lol. The ceramic coating definitely helps control temps better, while sitting still temps rose very slowly and stabilized around 84 F tops (70 F outside)...in every other test it would just keep climbing and climbing the longer you sat still. I am loving the ceramic coating I can't wait to do more testing.

9/25/11 Update : So with a temperature closer to 80 I did another test, looks like the pipes do a decent job of keeping the temps moderately lower than without the ceramic-coat. I think this is the best impression I'll be able to get until I get another really hot day to see how much heat soak it prevents when it's really heating up. Temps went up several degrees quickly at first when idling, then slowly ticked up over the next couple minutes.

9/29/11 Update : In some of my further testing I started seeing really hot temps, so I took the CAI off put it back on taking time with all the connections. That fixed it and temps returned to normal readings so I did some stress testing last night. By stress I just mean driving really hard so the engine was blazing hot and then seeing the IAT while moving and idling. I then just let the car sit there for 20 minutes after I got where I was going and took the max IAT it saw too. This thing is great, temperatures are lower than I've ever seen (77 while moving!) and it couldn't go above 110 when sitting there, I saw it ticking between 109 and 110. Awesome. Only thing to note is the ceramic coating scratches easily

11/20/11 Update : Just did more testing after adding CXJ Thermal Spacers. These things definitely help control idle temps anywhere from 10-23 degrees in multiple tests. Looks like even with a plastic manifold we are benefiting from heat reduction with the intake spacers. Great work Cory!

Here are some pics.

Before ceramic coating



After ceramic coating/thermal barrier

 

Very nice and clean. Will be doing mine very soon after I get all the parts needed

 

definitely looks clean bro! did u use the filter nd pipe from d r2c?

 

Nice work in doing the comparism.

Well, I did mine R2c vs Stock. Stock wins overall!!! This is on the 6thgen, of course. Don't know about the 7thgen. But the heat in that engine is just too much! That is why I think the CAI comes out better than the SRI.

The R2c is really just for the racing sound and its looks in the engine bay.

I had it for 2 weeks. And I lost low end, gained in midrange. But when I put stock back, I enjoyed gaining low end and I promise that from start (0) to 120mph, stock was faster than R2c. Since stock is really a CAI, I decided to sell my R2c only after 2 weeks of use and went back to stock. And I have not looked back ever since.

Oh, and I did lose a lot of mpg with the R2c, compared with my stock. Now with stock, I am seeing my gains on mpg come back. So, SRI vs CAI, I think CAI would give one more mpg.

 

+4

 

Nicely done man. Goes to show how vast of an improvement a true CAI is over the SR setup for the VQ's. One thing you MIGHT want to consider to help bring in cooler air all the time- get the intake pipes ceramic coated. Less heat transfer from the hot engine bay to the intake pipe. There's a shop in Manassas, VA that does some outstanding work that I've been meaning to check out. Let me know if you'd wanna roll out there!

The funny thing is... I never lost any MPG's with my Stillen after install. The only poor mileage I saw was the first 1-2 weeks when the ECM was figuring out the new fuel trims. Since then, I averaged 30.2 mpg going roughly 75-80 mph coming back from ZDayZ (540 mile trip almost made on one tank of gas) and avg about 23 mpg with my 50 mile roundtrip commute daily.

 

Nice job again Dan. Mind sending me the measurements for all of the piping you used? Think i'm going to make mine out of thermal tubing. Feeling lazy and don't feel like trial and erroring the measurements

 

Yeah I've been looking at some ways to reduce heat soak for the pipes, whether it be heat wrap or what I don't know yet. Yeah I'd be down to check out that shop in in Manassas hit me up - curious what ceramic coating runs you.

I put my first short ram on in winter so didn't notice much of a mileage drop, now in the summer with all the rest of the mods on I am noticing it. Nice to be back up around 19-20 MPG again.


Thanks man, yeah no problem I'll get that together for ya. Was definitely "interesting" learning how to use a metal grinder to cut some of these tubes to the sizes I needed. Obviously you need to relocate your battery to make room, and you need to bend the horn (I think it's the horn?) out of the way cause it's right there in the front left fender. Is thermal tubing pricey?

 

Funny thing is with my R2C intake , I get 25 MPG, all highway 70-80mph

 

Yikes... and that's with hand calculating the mpg?

 

that's cause you're moving fast. with my Takeda I took a trip and average 29 MPG with average speed of 75. when you're moving and got cold air blasting in the grill it's not too bad. most of my driving is city though and so im stuck in traffic a lot, during my morning commute today i saw 20 MPG for the first time in a long time. it used to feel mushy whenever i tried to go off the line after sitting for a few minutes and now it is WAY more responsive.

i was looking at this heat wrap job this one guy did for his intake. i mean damn its ugly but if it can help stabilize idle temps is it worth it? : http://www.flex-innovations.com/intake_wrap.htm

by the way random question : do i need that little plastic box thats connected to the small intake hose or can i just use a hose to connect directly to the intake?

 

Yeah my mileage with the R2C has improved as well compared to stock, up to 24.9 average now over close to the last 1000 miles with 50/50 freeway/city driving. But then again, I live in the Seattle area and it has been a somewhat cool summer, most days only in the 75 degree range, so with external air temps lower I may have somewhat less issues with heat induced problems.

Looks good Ghozt. Good work!

 

If you want a clean intake pipe setup, go with a high temp ceramic coating instead of heat wrap. Will make the engine bay look MUCH cleaner while still preventing the intake pipe from getting scorching hot.

I believe that little plastic box is what's called a Helmholtz resonator that's inline with the PCV vent tube. I think iFuxWitUz popped it open once and found nothing inside. Just an empty chamber.

 

Okay cool thanks for the info. Any idea how much ceramic coating can run ya? I've seen some places that do reflective on the bottom and black on the top for optimum heat dispersion

 

Not a clue man. That's why I wanted to take a trip out there next week. Would like to go this weekend, but gotta see the sister, niece and bro-in-law.

If you can give me the length and dimensions of the pipe, can probably get you a quote when I go there next week.

 

This car has huge potential for NA power, IMO.

What size is the intake ID?

Here's a similar thread from the A33 guys:
http://forums.maxima.org/5th-generat...ai-vs-sri.html

And a few more of mild interest:
http://forums.maxima.org/5th-generat...i-rethink.html
http://forums.maxima.org/5th-generat...ton-3-5-a.html

 

I went with 3" ID cause the place where you snake it through into the fender is a tight fit already. I just drove around during lunch and man low end has some nice pick up now it reminds me of the CAI on my old whip. Thanks for the links I'm gonna check them out now

 

Good Job.

 

Actually after putting some thought into it i was hoping someone with more knowledge of engines could give me some input. How would modifying the stock intake box to run a SRI into it so the SRI is enclosed in it with an additional pipe running out the right side of the box down to where everyone is putting their custom CAIs work? Basically keep the stock setup and just run additional piping down behind the front left bumper. That way it gets cool air from both the stock intake and from the front left bumper.

There seems to be a science to how the air flows and the distance it flows that effects where in the band you get increased power. I'm not sure if would cause "turbulence" and make it worse, how it would effect MPG, or where the power increase would be with the above mentioned setup. Or if it would just make it worse....

 

Probably work very similarly, just get one of those adapter flanges that bolts on, cut a hole, and string some piping along. Not sure if it would create turbulence that negative affects it or what, but definitely an interesting idea.

Have you thought about maybe modifying the stock box to make it more open?

Then again if you just go with the CAI I think you'll like it, the power gains on low end make acceleration feel more even, and then around 50-60 the car just takes off.

Here are measurements for those curious:

The Takeda SRI piece is 10" long, 3" diameter except near the tip where it enlarges to 4". I used a 4-3" reducer and ran all of the piping at 3".

The angled piece I used is about 4" before the bend (which I guess is about 45 degrees) and then 8" after the bend (so 12" total with a 45 degree bend)

Then there are two short radius 90 degree elbows, so that's 3" x 3" for each of them.

Finally (we're down in the fender now so not sure if this needs it), another 3-4" reducer, a 4" wide pipe that is 3" long, and it connects to the filter there.

Here's a pic

 

Thanks Dan. Yeah i was just wondering if the intake would benefit from getting air from the stock intake as well as the CAI area.

 

I'm curious too how that'd work. The only stock piece I used is I left my intake duct from the grill on so it can at the very least guide cold air from the grill onto my upper intake pipe - not sure if it actually helps or not but figure it can't hurt.

Think I'm going to experiment with some heat wrap since it isn't too expensive and wrap the intake pipes and see how it affects things. If it's enough of a drop in temp I might just have them ceramic coated.

 

if anyone wants to help me build one for $ lemme know, obviously id pay for all the parts just need someone with the know-how to help me install it, im on long island PM me if interested

 

honestly the CAI part you can mostly do yourself, just requires a flathead screwdriver and taking off the front left wheel so you can work freely in the fender area. had to trim a pipe which required a metal grinder/cutter and metal file to smooth the edges. all of the piping fits together easily using the black silicone sleeves to hold them together with metal rings that tighten to make a nice seal.

the pain in the butt was the battery relocation, which if you're not comfortable doing i'd definitely have a pro (or someone who knows) do it cause you don't want that thing flying around in your trunk.

FYI I got the longer pipe from Pepboys, was $40 and I had to cut several inches off the end cause it was too long. if you order normal 90 degree pipes you'll have to trim some of the pipe or get short radius 90 degree pipes which fit perfect. all of the sleeves i got from intakehoses.com which has a great selection of piping and sleeves if you wanna check it out.

Keep in mind what I used only works perfect off the Takeda SRI, not sure if it will work perfect for other SRI's.

 

Would you mind giving me measurements of your Takeda and r2c filters please? Wondering if i can just modify the stock box, or if i'll have to custom make one.

 

Good work, Wally is a good guy, always trying to make his ride faster.

 

Update : added some new tests and pics

 

good job bro! im glad someone actually did this other then me, and voucher the benefits of a TRUE CAI its def WORTH the extra $150 you spend to make it...

HEAT WRAP the pipe in engine bay dont bother with the ceramic.

 

Here is a link for some useful products. I'd would stick the the outward reflective wraps like those used to protect a starter or battery, rather than exhaust wraps which are designed to keep heat in. My .02

http://www.summitracing.com/search/?...t%20wrap&dds=1

TK

 

Yeah after more research I'm leaning towards a thermal barrier on the inside of the pipe with a ceramic coating on the outside to help as well. Turns out won't be much ($40-70) and the heat wrap+silicone spray was like $50 and would have looked terrible so thats an easy choice.

Even though my mileage isn't as high as some of my first tests, I am still loving the power this thing gives me. I finally feel like the car doesn't suck from 10-40.

 

Also, I should add that I recently bought an r2c, and it ran great. Actually it's a bit loud for my taste in this car so I may go back to stock. Performance was good with no notice of loss in low-end. Then, last two days it felt sluggish...especially in the low end. At first I was concerned the ecm adjusted and it got worse. So I popped the hood and looked closely...the hose clamp on the box side of the rubber coupling was loose. Not to where it could come off, but def where air could be sucked in. Bad part about that is it's past the air sensor so it was basically sucking in unmetered air, and probably running lean as hell. I tightened it down really well and voila, fixed. Car runs great again.

Moral of story, guys, check all your connections, a small air leak can make a car run like crap. And vendors, please make your pipes with beaded ends so hose clamps lock on better.

TK

 

Nice man, glad you are enjoying the R2C and that you figured that problem out. A friend of mine installed an R2C and his motor kept dying whenever he came to a stop. Popped his hood to find the R2C filter completely knocked off!

I definitely agree with you about those beaded ends, I got my 90 degree pipes with beaded ends for that exact reason such a better connection and seal. If you gotta work with what they gave you just make sure that connection is tight!

 

So I took the pipes off cause I'm dropping them off tomorrow to get ceramic-coated with an internal heat barrier as well, figured I'd get some numbers from the stock intake in the meantime. My immediate reaction is I hate the stock intake...it's so quiet and I definitely feel the loss of power compared to the CAI...barely sounds/feels like I'm pushing the gas pedal even when I'm flooring it. Man I can't wait to get the pipes back on..

Stock Intake Test 1 - Temperature : 84 F, humidity 55%, 7:30 PM

Average AIT while not moving : 115 F
Average AIT while travelling ~50 : 98 F
Average MPG : 17.5
Average MPH : 21.5 MPH

Conclusion : not too bad in terms of temperatures, although it wasn't dropping below 98 at all and definitely quickly rose above 100 when sitting still. mileage was a little worse, but not by much. the sound is completely wack, and the lack of power is depressing...

Will be updating with a few more stock intake tests at different temps, and obviously doing some CAI tests after it comes back from being coated.

 

if those numbers look good once u get the pipes back most likely gonna try and build one off the r2c with internal barrier and ceramic outer

 

Can't wait for the finished product and how long Ghozt before you put a group buy together on a battery relocate kit and True CAI for 7th Gen owners I kid

 

its supposed to reduce heat transfer by 25% so hopefully it will be worth it. if not this is still fun trying anyway

 

Len has actually been doing some research on the thermal barrier for intake pipes the past week or so since I stopped by last week to get quotes for P/C and your ceramic coating. Look forward to hangin out at the meet tonight dude

 

http://www.amazon.com/gp/product/B00...NM4T8WG03R6SA3

There you go. Best stuff around. Just cut it to size and stick it on

 

any updates on the numbers now that its ceramic and thermal coated?

 

the place they're being done at is overloaded with work, i should have them back in a week or two