posted on January 10, 2012 09:40
Project 370Z: Part 1 - Testing the AEM ETI Cold Air Intake
By Mike Kojima
Nissan’s 370Z is a pretty damn good car. It is a nice improvement over the already good 350Z; it is more powerful, handles better, is lighter, stiffer and faster. We wonder why it doesn’t sell all that well as we feel that it is a class leading car at a reasonable price. Perhaps in this sluggish economy, the market for a mid priced two seat sports car, which for many people is a second or third car is too much of a luxury.
|With two throttle bodies, two air flow meters and two airboxes, the 370Z has quite a complicated intake system.
Nevertheless, we are going to visit the 370Z and work it over to improve its track day prowess without compromising its street drivability. We are also going to see how well it does in street class time attack. Now we are not starting off looking for a car that is going to break street class records but we will find out just how competitive we can make the car while keeping it fully streetable, which means no gutting, no removing things like the A/C and no impractical, easily breakable aero.
|Our first step was to do a baseline dyno on our Project 370Z. AEM's Mustang dyno is very conservative so it's important to look at the change in power numbers, not just the peak numbers.
For our first round of mods, we tested the remarkable AEM ETI cold air intake. If you are into modding the 370Z you know that the car does not respond too well to typical intake tuning. Most of the cold air intakes on the market for the 370Z get into a fight with the car’s ECU and after the initial few dyno runs do not register much of a power gain, some popular intakes have even registered a loss in power during some of our prior testing.
|We were pleased with AEM's instructions which were pretty concise and easy to understand.
|We first laid out all of the parts to orient ourselves. The AEM kit was very complete.
|Next we put the car up on a rack, removed the front wheels, the belly pan and inner fender liners. This is a pretty involved air intake installation.
Tuesday, January 10, 2012 9:46 AM
So it sounds to me like the ETI part of this simply modifies the air signal so that it doesn't deviate too far from the stock reading. This reminds me of the S-AFC in a sense. So basically the car is running leaner without the air meter realizing it and the O2 simply compensates to balance things out. Clever work-around on the air metering system.
Tuesday, January 10, 2012 10:08 AM
On the opening comment about the 370Z not selling well, I think it may be a styling preference as well as our crappy economy.
I think the 350Z was pretty good looking and that Nissan made a styling mistake by making the body appear fatter and more massive with smaller windows and a larger fender opening break (similar to the most recent Mitsu Eclipse). The overall effect smacks of copying the Lexus SC 430 "I'm-a-female-exec-and-I've-arrived" coupe. Especially in pearlescent white...
Anyway, it's a shame Nissan didn't take the improved chassis and drivetrain and put it under less porky-looking sheet metal. But, then again, one of my faves is the Ferrari 288 GTO, so go figure. Doorstop v. bubbly w/ fangs...Just style prefs...
For performance though, I can't wait to test drive one. Still love the sound of the 3.7 V6 uncorked and lightly muffled.
Tuesday, January 10, 2012 11:20 AM
Although the 370z is marketed as a sports car, there are magazine-documented incidences of the 370z overheating and experiencing sudden and drastic braking power loss during track use. This would be the reason I wouldn't buy one.
Tuesday, January 10, 2012 11:37 AM
jeffball: You're exactly right. Not knocking on AEM at all - they make the best aftermarket intake kits around in my opnion, but the original AFC (not super AFC) was released for this same exact reason....in 1993. So in effect, the Japanese had an "ETI" 18 years ago. Tuners then latched on to the AFC for the coincidental benefit of fuel tuneability. Now people bash the S-AFC for being a piggyback, but little do they know they are trying to use it for something it was never intended for.
oldx18: The 370z looks far more muscular than a 350z in my opinion. It does not remind me of an SC430 whatsoever. To me, Nissan made the 370z look really good, but like you said its just a matter of opinion.
fong: Yes, that is completely lame how Nissan did the Nazi (or cheap out depending on how you look at it) thing on the 370z, but it is easily overcome by the additional of fluid coolers.
Tuesday, January 10, 2012 11:39 AM
Easily fixed with an oil cooler which we are going to cover later.
Tuesday, January 10, 2012 1:43 PM
I definitely feel like the 370z is very appealing styling, powerwise, etc. I feel like they took the masculine 350z lines and accented it with 240z nosalgia. Of course it could be lighter, but that's what we have the Fr-S/BRZ for!
Intakewise, I'll give it a toss up between AEM and K&N. Both excellent quality! I've heard the Stillen intake is also excellent for the 370 and I'm 90% sure they use K&N filters.
Tuesday, January 10, 2012 2:26 PM
is there any sort tuning software for the 370? kinda like Osiris for the 350?
Tuesday, January 10, 2012 3:02 PM
@warmmilk STILLEN uses the Uprev Osiris software for the 370Z.
Tuesday, January 10, 2012 3:04 PM
The 370Z dyno charts look nearly fake, because they respond really well to mods. You just about take the lines, and just move them up. I think its all associated with the VVEL.
2012 has some changes like a integrated oil cooler, but it will probably still be similar to the early cars, and need a outboard cooler.
The STILLEN intakes use K&N filters.
Tuesday, January 10, 2012 3:08 PM
and the Stillin intakes make less power
Tuesday, January 10, 2012 3:20 PM
It is NOT fake.
Tuesday, January 10, 2012 4:13 PM
i was there watching the dyno runs happen, i promise its not fake
Tuesday, January 10, 2012 6:29 PM
Tyndago wasn't implying they were fake, just that the car responds so well that it LOOKS fake because the torque line is shifted almost perfectly up. It basically shows a constant VE improvement across the board, which is the goal of course of reducing pressure drop in the take and getting a colder air source.
Tuesday, January 10, 2012 6:31 PM
if there's a real tuning solution, why not just get a real tune instead of the ETI thing?
Tuesday, January 10, 2012 6:39 PM
the ETI setup is not a replacement for getting the car tuned, it allows the setup to run more efficiently by getting the MAF signals to read correctly. Doing a dyno tune with these intakes will help it yield better results then a dyno tune with a intake setup not like this.
Tuesday, January 10, 2012 6:50 PM
if you're tuning the ECU for these intakes, wouldn't the ETI distort the signal? based on the article, they're there to make it play nice with the ECU by showing it what it wants to see. but if you're getting a real tune don't you want the MAF to see whats actually going on and not a "corrected" signal? or did I misunderstand what the ETI does?
Tuesday, January 10, 2012 6:51 PM
No it won't mess stuff up.
Tuesday, January 10, 2012 6:53 PM
the AEM ETI intakes can 100% be dyno tuned (for example with UpRev software) with zero issues
Tuesday, January 10, 2012 9:27 PM
Damn Mike, reading comprehension owns joo. I said, " charts look nearly fake, because they respond really well to mods".
I don't really care if you were standing there watching it, because I understand that its not fake. I was making a bit of a joke, but seems to be lost on the peanut gallery.
I look at dyno charts of 370Z's every day. They respond really well. VVEL manages to do some great stuff.
I know that having the air filters in front of the radiator, or down low and in front of the tires, I would rather have them in front of the radiator.
Tuesday, January 10, 2012 9:46 PM
Back to you, I just said it was not fake. Why do you think in front of the radiator is better? I have tested the Stillen intake extensivly and found it to make much less power with the front fasia in place, at least with large dyno fans blowing. Perhaps on the road the effect is less. The effect on power was considerable. I think thr power difference was due to the intake sucking hotter air.
Tuesday, January 10, 2012 10:02 PM
The VVEL does a nice job, but I think that is also what puts a ton of heat into the oil. Its a great engine, handicapped by a few cost saving measures. Makes aftermarket camshafts obsolete?
There is more than one way to skin a cat, and we all know that most dyno fans don't blow much air.
How does the ETI do with auto trans? All the modern Nissan cars with auto trans use the MAF load to control shift points. Messing with the MAF, makes the everything unhappy.
Wednesday, January 11, 2012 12:11 AM
The Stillen intake worked well with the auto trans (we tested it on both MT and AT versions) when we tested it so you should figure that the ETI intake should have less of an affect on it.
Of all the intakes we tested only the Stillen and the AEM make any appreciable difference to be worth reporting on.Stillen 370z Intake
The issue is with a moving vehicle, does enough cool air reach the filters to avoid the issue we had and make the Stillen's intake reach its full potential. Our dyno has really a big powerful fan, still probably not the airflow of going 60 mph.
Wednesday, January 11, 2012 10:23 AM
To see which makes more power why don't you do a few 4th or 5th gear pulls and time how Long it takes to go from start "mph" to end "mph" with each intake on, average the runs and see what happens.
Wednesday, January 11, 2012 10:24 AM
On a private road of course
Wednesday, January 11, 2012 10:47 AM
We live in the middle of a huge city, you can't do 4-5th gear pulls around here, it is too congested in at night. We don't know of a private road that we can use that is long enough to do that either. You can't hit those speeds on the track around here with this sort of car. That would be a good way to see if the Stillen works better. Bumper venting would probably help the Stillen.
Wednesday, January 11, 2012 1:50 PM
My comments keep being deleted when I try and post, so this is a test. I wrote a bunch of good stuff about MAF sensor voltages, ECU calibration tables and O2 sensor feedback. Instead I will just say that the AEM Mustang dyno is the bane of my existance. I spent way too much time as an engineer there playing dyno repair technitian.
Wednesday, January 11, 2012 2:06 PM
No one is deleting posts intentionaly from our end.
Wednesday, January 11, 2012 2:27 PM
Its not intentinal deleting. Its like a timeout issue where there is not a fast enough response back when I hit add comment that it does a refresh and clears the screen.
Wednesday, January 11, 2012 3:01 PM
Yeah, that's why some of my posts have shrunk. Well, that and heavy workloads!
Wednesday, January 11, 2012 3:05 PM
I'll re-index the database to see about speeding the comment posting up.
Wednesday, January 11, 2012 6:18 PM
Aaron's the man!
Wednesday, January 11, 2012 6:25 PM
Mental note, don't write long posts...
Anyway, the voltage signal given to the ECU from the MAF reflects that actual flow rate of air that is going through the intake. If the MAF has a flow rate that equaled 2.0 V in the stock intake, in the modified intake that 2.0 V reading won't be the same flow rate. The ETI adjusts the signal so that the 2.0 V becomes something like 2.2 V instead to match the increased flow that is occuring with the modified intake. That keeps the fuel delivery matching the right air flow rates, which keeps the O2 sensor from exessively needing to trim the fuel tables.
Wednesday, January 11, 2012 6:35 PM
@Der Bruce - Aw thanks man, last thing I want is someone to get frustrated while we're having our virtual hangout.
@Merritt - Apologies for that. If too much of your heart goes into a message you can always Ctrl A then Ctrl C before submitting.
Thursday, January 12, 2012 8:14 PM
I'm glad to see this project car. I don't see many of them on the road but the package is pretty cool overall. The styling really does it for me, I like the sharp angles that have been added to give more vintage Z flavor. The power and weight numbers are also relatively impressive. I think in general, the car-buying public wants something more comfortable and practical, and with the advent of V6 Mustangs that are actually quick at a low price, the average guy isn't shelling out for the Z34. It's amazing how far we've come, as the E46 M3 really doesn't seem too impressive compared to some of the cars that an average joe can easily afford these days with some scrimping.
Thursday, January 12, 2012 9:10 PM
Nice article and AEM makes great stuff! I would have gotten on this but I've had the STILLEN set for around a year now. Speak of, I do notice that during some of the hottest and humid days in the FL panhandle, my Z(370) can be not so responsive. I do have the OEM bumper without any type of ventilation fabrication. So the thought has crossed my mind that during this scenario, it's probably harboring all that heat and the intakes are just getting heat soaked. It is after all stuck inside a non-ventilated bumper like meat in a dumpling and it's getting "steamed cooked" possible heat coming off of the radiator area. I'm moved to central FL since and I don't really experience this so much driving (excluding work traffic) because I'm consistently hitting 60ish+ MPH going to work or where ever(versus 4ish+ MPH back at home). So I think the speed times airflow idea does play a major factor with the STILLEN intake. So I think the AEM set would NOT experience this. AEM's design very much remind me of the kit I got for my RSX-S by Injen (CAI version) a long time ago. I didn't experience this at all with the Injen CAI the couple of years I had it and staying in the FL panhandle. Again this are just my thoughts and experience so I'm not saying this STILLEN product is bad at all. I'm very happy with them still and plan on keeping them until the next phase.
Friday, January 13, 2012 3:10 PM
ooohhh, I get it now... the ETI corrects for tube diameter change from the stock MAF housing... Thanks for the explanation Merritt
Sunday, January 15, 2012 11:47 AM
The reason the 370 isn't flying off the lots is because 36k for the 370Z (with the REQUIRED sport package) is a tall order for what you're getting.