The Injen design for the 5/5.5th Gen is 39" long and it's really restrictive at higher rpm!!!!!

 

so is it only the 5.5s that get timing adjutments base on air temp sensor? bc i was under the assumption it doesnt change anything on the 4th gens?

 

If it has an IAT sensor, it is very likely that the ECU will retard timing when the engine is breathing in hot air. Not sure on the 4th gen, though...

I do find that a shorter intake is technically better for power (not super short, total of around 30" including TB/elbow), but the colder air keeping ECU from retarding timing is enough to trump it just about every time.

Optimally, you would probably want to go for a sealed airbox where the battery's stock location is that is fed air from the fender.

 

it has it, i guess ill make a thread on the 4th gen and see what the masses say. my car has a dead iat and it runs fine, maybe im leaving some power on the table with it.

 

It's possible that it would failsafe some pretty low timing for that if it does adjust timing based on IATs. I've heard 4th gen ignition timing is horribly inefficient even when running right, though.

 

I realize that this is an oldish thread however, I had a few questions:

1. The hole you cut seams close to the shock tower. Does the fender provide any structural support for the shock tower? Would cutting the intake hole therefore compromise structural integrity?
2. Is the stock ecu capable of handling the longer air intake length or would you need a tune/re-flash?
3. How does the Cattman CAI compare to the custom ones you guys have?

 

1. As long as the hole is cut ROUND and cut well and smooth, the effect it has on strength should be minimal to non-existant. I worried about this too but as long as the hole is cut well, and in the proper location (fender side of main weld), then it will be ok.

2. The short answer is no, but anyone can argue this, and win too.
So let's go with IMO, the stock ECU has limited capabilites in the 5th gen Maxima. The 5.5 (your generation) is better than the 2000/2001 ECU, but it's still no marvel.
Because the 5.5 has fly by wire TB though there is more that can be done/controlled, it also has a better intake temp sensor design that allows better management.
Ideally, a tune should be done regardless, however, there are few to no companies that tune our ECU's anymore as far as I'm aware.

But running a better intake will still give you better power across the range, especially on the 5.5, even without a tune.

3. I've never heard of a Cattman CAI, but i do know that at this point, NO ONE makes a TRUE CAI for this car. If you want a TRUE CAI you have to cut the fender. I was getting ready to to this acutally but decided to sell my car. I have all the components necessary to make it in 3" aluminum sitting in a box in my basement lol.

 

Cattman cai same as PR cai I believe. Have to do a custom setup and cut like TMax3k says.

 

Ive been considering doing this mainly because my 5.5 runs like a pig during the summer here in Colorado. On a hot day the car feels like a 4 cylinder. Density altitude is a huge problem.

I realize this isnt the thread for aftermarket tuning options, but what would you recommend? And would a tune be able to respond to changes in altitude? I can drive from 5000Ft in elevation to 14000Ft in elevation in about an hour.

I was kinda surprised how much of a difference the GAB mod made. If I was confident the seal on the filter was tight id probably still be running it that way.

On the Cattman website under intakes (CAIG5-A), theres a CAI intake listed that warns " Installation requires 3.25” drill-mounted hole saw."

 

If you're currently using the OEM Air-Box/Snorkel this cheap little mod will help get cooler air to the inlet.
http://forums.maxima.org/5th-generat...01-maxima.html

 

Try and call Brian Catts if you like, however he's moved on to other business ventures. The only thing he does anymore are group-buys for exhausts, primarily 3.0" cat-backs.

There was a time when he held inventory and ran middle-man for commonly needed Maxima after-market parts, but those days are gone. His website hasn't been updated in four or five years. Ignore the website.

All things come to an end. Even good things, like Cattman Performance.

 

True enough, and the list of Maxima aftermarket parts gets smaller & smaller.

On a slightly topic related side note. Correct me if I'm wrong Rochester. But from the one pic posted of G37 engine bay it looks like the air-box inlets suck air from behind the grill. Perhaps a couple of cheap plastic AZ hood scoops hidden back there could "Divert(extra)Cool Air" to the inlets.

 

You don't want anything other than stock, stock with the CAD mod that BOBPEZZ just linked, or a TRUE CAI.

Anything else will make it intolerably worse.

I'm far from the best guy to answer this. I can tell you that your car should adapt to different altitudes on it's own, the extent to which is dependant on the MAP/MAFS impact on Fuel/timing maps. This I don't know about.

The car should sense the incoming air pressure, which is directly related to Ambient air pressure, which is directly affected by altitude.

your biggest issue is whether you're running the ideal fuel OCTANE to accomodate the difference.

 

My gut reaction is to chuckle and say, "Um, no." But honestly, IDK the answer to that. So I'll just say, "Maybe." I'd have to look long and hard at it.

 

Thats unfortunate, I suppose a custom CAI wouldnt be too hard but drilling into the fender has me nervous. Also Rochester I saw your post on your new car and wanted to say that Ive driven a g37x and absolutely loved it. I'm (admittedly) kinda jealous.

Interesting idea, though Im also looking for more flow. The stock intake scoop is stupidly thin in terms of its inlet size.

I currently run 91 octane, which is the highest you can get around here. Regular is a measly 85.

 

FYI; A typical aftermarket 'intake' is 3" dia. tube that works out to 7.065 sq" actual inlet area. The OEM Snorkel inlet area is (by conservative calc.) ~8.5 sq", Air-box inlet area is 7.3125 sq", area = flow capacity & the Air-Box is a fairly large plenum. So the OEM system has equal or better capacity. It's a true CAI, & doesn't reduce torque like a SRI, due to the added length of the Snorkel/Air-Box etc. Not to mention the plastic OEM setup is less prone to heat-soak. The "CAD" mod reduces IAT by ~7deg F. on the OEM Snorkel/Air-Box. Which is pretty good, when you do the math. The other mod that would help with heat, is Phenolic intake spacers since your car is a 02 w/VQ35DE & aluminum IM. And the Home Depot PCV 'catch-can' would reduce intake charge dilution. http://forums.maxima.org/5th-generat...ml#post8270906

 

"That's thinkin' with your dipstick Johnny!"

 

I like the idea here, the engine bay gets so hot from the headers. I wonder if I can craft a quality inlet from the wheel well while retaining teh shorty berk intake.

 

I've suggested that many times^, on the 3.5 I think it'd be ideal to utilize an ICEBOX

 

Correct me if I'm wrong, but is an ICEBOX simply a cone filter housed in a box that is vented into the fender well?

 

Sorry to bump another old thread, but I have a couple questions I was hoping you could help explain. I'm in the process of trying to figure out how to optimize my intake setup, but am unsure of a few things.

The first would be the benefits of the stock midpipe/accordion. From this old thread, it was shown that the stock midpipe outperformed the Frankencar/straight midpipe. At what point would a larger diameter straight pipe being to outperform the stock accordion?


This article seems to show that Helmholtz resonators can be quite useful in tuning your intake system to give a boost in HP at a certain RPM. I noticed better throttle response when going from the Frankencar back to stock, but I imagine that if the midpipe were a much larger diameter, there could be gains realized from that, as opposed to a stock diameter pipe like the Frankencar.

This FTLRacing site mentions a lot of the things discussed in this thread, but my previously mentioned friend is skeptical of the idea that going from a 3.5" pipe down to a 3" TB somehow adds power. His response to my question was:

"The derivation of the Venturi effect assumes a constant flow rate through the entire system, including the venturi. His explanation kind of sounds like he is saying that reducing velocity will increase pressure (which is true), but how he goes from that to saying that this will increase the flow rate doesn't make any sense to me. (When his entire line of reasoning assumes constant flow rate).

However, my feeling is that the Venturi effect is only really applicable in a steady state situation, which is most definitely not the case here. So, maybe he is trying to hand wave an explanation to explain some measured results. I would definitely defer if anyone has measured the effect of a larger diameter outside the throttle body, otherwise I would say this is probably unproven snake oil."

So, my question is if anyone has quantitative proof that decreasing the diameter of the intake piping going into the TB is actually beneficial? I understand that you want the shortest amount of piping in front of the TB, but have yet to see anything about the gradual decrease in diameter before the TB being beneficial.

My idea for the "best" intake would be a SRI in an (otherwise) airtight box that pulls air from the fenderwell through a tube. This way, you get all the benefits of having the shortest amount of intake piping while still getting the cold air benefits of a true CAI. As far as what piping to use, I'm still not sold on getting rid of my stock midpipe/accordion and going back to a straight pipe.

 

'Tuner' has stated this previously (see quote). Your idea for a 'best' intake doesn't deviate much from the OEM airbox design. Which when you look at it, is similar to an SRI from the filter back. And a CAI from the filter forward, since the snorkel gets air from the grill area. Sparks & NmexMax have said the OEM airbox isn't that bad for performance (see post) http://forums.maxima.org/8175998-post16.html . So you're not too far off base. Perhaps running a hose from the fender-well to the OEM air-box would be a good start.

 

I've learned a few things from this thread. I came from a SRI setup, let me tell you, it was .
Then I moved up to a true CAI. I felt the difference, especially from mid to high. Yes I sacrificed sound over power but I'll take power any time.
Now its time to improve my CAI. I got some couple of ideas from this thread.

 

I think itd be interesting to run that into the top of the stock air box kinda creating a CAI-GAB mod. Clarence with the hood would be an issue though...

 

As a followup to the icebox idea.....if the cone filter is in a sealed box that pulls air only from the fender, how is that any different than the filter actually being located in the fender? If the filter is pulling air through a 3-3.5" pipe from the fender, that seems like the same thing as the filter just being in the fender and pulling through a long tube after the filter, as opposed to before it. Or could the losses associated with pulling through a long pipe be negated by using massive diameter tubing (an idea already talked about in relation to normal CAIs)?

On the same topic, on 4th gens at least, the IAT sensor can only reach so far, just about to the fender. I can't see a way to actually locate the sensor in the fender without cutting up some wiring and trying to extend it. If the IAT is in the engine bay but the filter is in the fender, I think most of the potential gains would go unrealized since the sensor would think the air is hotter than it actually is. Are people mounting the sensor in the filter or piping, or just leaving it hanging like I'm doing?

 

Most likely your IAT will be reading high intake temperatures since its hanging. I manged to squish in my IAT between the coupler before the MAF sensor.

I was tracking my intake temperature today. Lowest being 62, highest being 73 degrees. The more you idle, the more the intake temperature rises. Just putting it out there.

 

I never really thought about that. Normally the IAT is reading (moving) air that's inside the air box, which should be a little cooler than the air around the filter....but maybe not. It's all the same air, right? I can't think of a way to get it inside the airflow without causing a vacuum leak or squishing the wires. Where do most people mount the IAT when they get a cone filter?

 

just got my heat shield installed with a pipe running from the lower bumper vent forcing air into the air filter box. Love the sound of the intake. Now all i gotta do is keep my foot out of it

 

$60 6th Gen intake with stillen popcharger

 

Two in a row, I love this!!! You guys rock sweet work on both accounts!!

To Lofty: Did you drill a hole in the inner fender where Fxrevolution ran his pipe through? You should, or you may be robbed of sufficient air flow. And with that set up you'll pull in mainly, if not all, cold air.

With it sealed somewhat like it is though, you're going to starve the car for air.

 

Underneath is wide open.

 

Have any pics of the hose? Im curious as to how you routed it.

 

Very nice! Timing should stay more advance cooler the air! Workmanship looks impressive!

 

Reaaaally? How you know this markymark?

local?

 

The old man can't move on they don't like him on the g forums.. maybe he tryed to start a titanium nuts and bolts trend lmao ...

 

There is a hole cut in the bottom to allow cold air in. I had it setup where a angled piece of aluminum behind the lower bumper vent was directing air toward the space behind the fog light to a pipe leading up to the filter but didn't like how much the fog light got in the way of air flow so i cut a hole in the slash guard and put a screen and metal mesh over the cut out and now it gets all its air from there. Not really worried about water since i live in upper SC or dirt too much because of the screen and mesh plus its in front of the tire.

 

So now this is a pic thread?