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Discussion Starter #1
Ok, what I'm going to do here is present the facts as determined by the HFXA (Houston FX Association) regarding the effectiveness of the Injen CAI on both a stcok RWD and AWD FX35 and give my own thoughts on the matter; others can feel free to chime in with their opinions.

A quick recap for those of you who've been off-world for the last couple of weeks: We met two weeks ago to install the Injen intake in DAVESNELLING's otherwise stock RWD FX35 (keeping in mind the intake was developed on an AWD and currently sold as an AWD only part). Upon installation, Dave's FX lost approx .2 sec in his 0-60 times (G-tech measured). Injentech said they never claimed the intake would reduce your 0-60 time and that the intake was geared toward top-end performance. FINE, however, based on the dynos they provided, we see no loss in the low end, so increased 0-60 times should not occur. At this point, the only logical conclusion was that there must be some difference between the RWD and AWD that is facilitating this condition. You can read more in any of the other related threads in this section.

Here's what we decided to do:
We (I) would make some G-tech runs in Dave's FX with the Injen, then immediately change it back to stock and make more runs. Then make runs in GeoFX's AWD in stock form, install the Injen and do runs again.

This is in no way a comprehensive test, looking at all aspects. Here's what we were looking for:
-increased performance off the line (0-60 times)
-difference in how the intake works on a RWD as opposed to an AWD
-bring up a couple of points regarding our results vs. Injen's Dynos

Conditions on the test day were:
85 deg, light breeze, sea level, low humidity, flat section of road. Keep in mind we do not intend these G-tech times to be compared to anything but themselves in regards to before and after performance with the Injen intake.

Here are the results (all runs in manual mode and all of this took place within 1.5 hours):

Dave's RWD w/ Injen:
1. 6.77
2. 6.88
3. 6.94
4. 6.81
ave 0-60 = 6.85

Dave's RWD back to stock:
1. 6.59
2. 6.61
3. 6.62
4. 6.63
ave 0-60 = 6.61

That's .24 sec faster 0-60 for the RWD stock than with the Injen. When switched back to stock, the car was quieter, the bottom end was back and it pulled smooth to redline, whereas with the Injen, the bottom end seemed to be lacking with a surge felt above 5k rpm. Now, lets try the AWD.

GeoFX's AWD stock:
1. 7.03
2. 7.10
3. 7.10
4. 7.11
ave 0-60 = 7.09

GeoFX's AWD w/ Injen (I did extra runs here):
1. 7.16
2. 7.33
3. 7.36
4. 7.44
5. 7.51 (shifted slightly early here)
6. 7.44
ave 0-60 (all runs) = 7.37
ave 0-60 (taking out the early shift run) = 7.35
ave 0-60 (dropping the fastest and slowest runs) = 7.39
ave of the above three = 7.37 sec 0-60

That's .28 sec 0-60 SLOWER for the AWD with the Injen than stock. Same feeling as in the RWD comparing stcok to the Injen.

Immediately, we can conclude without a shodow of a doubt that the Injen behaves exactly the same on an AWD as it does the RWD.

We can also conclude without a doubt that the Injen does not help and in fact is a detriment to your launch, the low end of the powerband and your 0-60 time. This DOES NOT necessarily mean the intake does nothing. Before showing the AWD Injen results to GeoFX, I had him go drive his car and come back with his impressions. He came back smiling, saying he felt that it helped, could really feel it in the top end (above 5k) and loved the sound. I then showed him the results and he was pretty amazed that the car was actually slower on take-off. He decided he'd rather go back to stock and the Injen is now a very shiny ornament in Dave's garage and he's SERIOUSLY considering ordering one of Mr. Stillen's meat grinders. :D

At this point, I'm not passing judgement on the Injen; you can draw your own conclusions. The intake DOES indeed feel as if it's helping in the top end, it DOES sound great and it MAY compliment other breathing mods nicely, HOWEVER, the fact remains that it makes your car slower where it counts for most of us; your launch. If you spend the majority of your time driving above 5k rpm, then it may very well be a great addition for you (even then, I'm not sure, b/c in doing 0-60 runs, you use ALL of the RPM band in the first two gears, so even if it does help more up top while losing a bit down low, you STILL are slower. Perhaps it would be more acurate to say that this part is not for the dragstrip, but may help in a roadcourse situation.), but be aware that you apparently lose some in the low end as a tradeoff.

This raises the question to Injentech: How can this be, based on the dyno results that show gains accross the RPM range?

The other point I want to mention is the ECU issue (b/c I know soebody'll bring it up). It is my firm beliefe that in the case of these mods, you will see the largest possible gains BEFORE it has a chance to adjust, not the other way around. I've covered this elsewhere, but the ECU tries to maintain the A/F ratios within a certain range, so when you add a part that changes those ratios, the ECU will adjust over time to bring them back into spec. Basically, what this means (especially for an intake that sits right in front of (or incorparates, in this case) the MAF sensor, is that the ECU will DETUNE your mod over time. Injen has even said that it's a good idea to reset your ECU every so often; this is why.

The interesting thing about this is that this makes sense when going from a more restrictive intake to an aftermarket one. You add more air, the ECU will adjust over time. I WAS slightly concerned that we may see worse results when switching Dave's back to stock, because we'd be replacing a free-er flowing intake with the more restrictive stock one when the ECU had already adjusted to the high-flow. I thought that in this case, the stock times might be worse until the ECU adjusted in the opposite direction, but this was not the case. So either:

- the stcok intake actually flows MORE than the injen (interesting note: the Injen's inside pipe diameter was measured at 2 13/16", while the stock tube has an inside diameter of 3 1/4"),

OR

- The ECU adjusts very quickly (notice how quick the first Injen run on the AWD was compared to the stock runs (yet still slower). The times then increased from the second run on).

OR

- The ECU doesn't adjust much at all.


Anyway, there it is and there are my thoughts. You can draw your own conclusions and I'm sure the other guys will chime in with there thoughts as well. I would just like to re-iterate that we are in no way "out to get" Injen or bash their product. We're just real guys looking for real world results and this is what we got.
 

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...mmmm let's see : Injen $240 shipped - shiny stuff, not too happy! / Stillen $180 shipped (with Chrome badge!) HAPPY! / JWT & Stillen STB $240 (notice same as Injen-not too happy) - VERY HAPPY ! / aaaahhhelp me out here guys - Sincity, bradical (oh btw, thank you) , brn(gimme a CAI for my 45)jug........mmmm?? patient grasshopper save $$$$!!!! VERY VERY HAPPY! JWT & STB for $240 Please.
 

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Discussion Starter #3
Also note I'm not trying to make any comparisons between intakes. We did no such testing on other intakes on an otherwise stock vehicle. My opinion is that you won't get much of any gains with any intake by itself, but that you have the least chance of losing anything down low with the JWT or Stillen, as they keep the stock configuration, tube length, MAF position, etc. and just facilitate the easier entry of more and smoother air.
 

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Before showing the AWD Injen results to GeoFX, I had him go drive his car and come back with his impressions. He came back smiling, saying he felt that it helped, could really feel it in the top end (above 5k) and loved the sound. I then showed him the results and he was pretty amazed that the car was actually slower on take-off.
MY butt-dyno indicated better throttle response and seemingly better pickup from 40 mph on. Also, the sound was very cool. It wasn't until I saw the 0-60 numbers that I thought WTF!! My initial response to the InJen seemed to be in line with fx343 and sonoman1's butt-dyno findings. It would've been nice if fx343, sonoman1, or InJen could've done some 0-60 A/B tests (stock vs. InJen) as well for further verification of our results.
 

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Guys, thanks for taking a Saturday to do this. Very interesting. It would been even more interesting if you guys had a Stillen or JWT to test.

Like I told Piniti this AM, I have already purchased a pre-owned JWT and Z-Tube (claimed to have about 300 miles-who knows) on Ebay for $143 shipped. Not a great price but I figured I saved about $60 from a new JWT and Z-Tube (factoring in shipping) and with that money I purchased one of Insaneanime's (z-treme.com) grounding kits ($75). Will be cancelling the Injen tomorrow AM.

I didn't realize that the inner diameter of the Injen is smaller than stock. With this new info, I wonder if the detriment to the Injen is: 1) Length of tube, 2) Diameter of tube, and 3) Location of MAF sensor. See my prior posting:

http://www.infinitifx.org/phpBB2/viewtopic.php?t=1432

Piniti-At this point, if I were you, I would probably go with either Stillen or JWT. With a JWT, it will be much cheaper, and MAYBE.....when the FX specific intake comes out from JWT, we may be able to upgrade the heatshield.
 

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What I'm amazed at is the effect of temperature and humidity on 0-60 times. Same G-tech meter, driver, and gas. Straight, flat roads used for both runs.

7/31/2004: High 97 degrees (from weather.com). Est. 70% humidity.

#2 GeoFX's stock FX35 AWD (1/3 tank)
1. 7.62
2. 7.69
3. 7.61
4. 7.76 (shifted a split-second early)
5. 7.68 (auto)
ave good manual runs = 7.64 sec 0-60

8/12/2004: High 89 degrees. Humidity 37% ( both from weather.com)

GeoFX's AWD stock (w/ two-degree timing advance):
1. 7.03
2. 7.10
3. 7.10
4. 7.11
ave 0-60 = 7.09

I'm not really sure how much of an impact the timing advance makes but that is a 0.6 sec difference in 0-60 times with a stock FX35 AWD! The **** with intakes. I want to move back to California!! 8)
 

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Discussion Starter #7
GeoFX said:
What I'm amazed at is the effect of temperature and humidity on 0-60 times. Same G-tech meter, driver, and gas. Straight, flat roads used for both runs.

7/31/2004: High 97 degrees (from weather.com). Est. 80% humidity.

#2 GeoFX's stock FX35 AWD (1/3 tank)
1. 7.62
2. 7.69
3. 7.61
4. 7.76 (shifted a split-second early)
5. 7.68 (auto)
ave good manual runs = 7.64 sec 0-60

8/12/2004: High 89 degrees. Humidity 37% ( both from weather.com)

GeoFX's AWD stock (w/ two-degree timing advance):
1. 7.03
2. 7.10
3. 7.10
4. 7.11
ave 0-60 = 7.09

I'm not really sure how much of an impact the timing advance makes but that is a 0.6 sec difference in 0-60 times with a stock FX35 AWD! The **** with intakes. I want to move back to California!! 8)
Yes, this is also how another member (name escapes me at the moment) achieved 6.38 with an AWD and Stillen intake at 50 degrees.

In regards to your time differences, remember you also had your timing advanced 2 degrees between testing days, so that may be a factor as well.
 

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Drove around this morning-FX feels fine . I just don't spend enough of my driving time above 5000RPM , so I have to let this one go. But I do miss the sound. It was present evan at lower RPMs.Looks like I'll have to find something else to install. And then we can start this whole process all over again.
 

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Discussion Starter #9
DAVESNELLING said:
Looks like I'll have to find something else to install. And then we can start this whole process all over again.
Hmm, and what, praytell, might that be? :wink:
 

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Point of interest: Too bad MUST. didn't take a run to see how his mods. stack up! / WHY? If you compare car and driver, stock and w/Injen times in aug. vs. times in july, dave and geo both ran @.4 better in aug. Use MUST. times in july and quicken (reduce) by the same .4 and you will see that MUST. and Dave were reall......well that should at least make you feel a little better Dave. / ($1000 worth of mods. = .2) do you really think the PULLY is helping the bottom end?) peace-out, dudes. (the responce that was given below was a DEFENSE that we all expected - not about making his host feel better) ...as you read below , you will understand that it is all about the individual.
 

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The numbers dont lie. All runs were exactly the same for both AWD and RWD. What gets me is that the numbers actually improved once the cars were back to stock!!!

I also would like to quote MGFR, "We're just real guys looking for real world results and this is what we got."

I dont want to pay $240 just so my car would go slower:)
 

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Discussion Starter #12
PINITI-FX said:
Point of interest: Too bad MUST. didn't take a run to see how his mods. stack up! / WHY? If you compare car and driver, stock and w/Injen times in aug. vs. times in july, dave and geo both ran @.4 better in aug. Use MUST. times in july and quicken (reduce) by the same .4 and you will see that MUST. and Dave were reall......well that should at least make you feel a little better Dave. peace-out, dudes.
I have no idea what you just said... if you're trying to compare Dave's stock times to my times from the last meet, don't bother. I did runs on Sat as well before I headed over to dave's and ran 6.37 and averaged 6.4 WITH some wheelspin (I had the same .2 sec advantage back at the last meet). I have to admit, though, Dave's FX seems pretty fast for being stock; he had .2 advantage over John's stock RWD (though John runs 87 octane, while Dave runs 93 and had his timing advanced 2 deg (still gotta get that done) the day before). I run Chevron 91 octane, BTW (personal choice). See the "launch technique" thread for more info.
 

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MustGoFastR said:
In regards to your time differences, remember you also had your timing advanced 2 degrees between testing days, so that may be a factor as well.
Hey MGFR, can you get some G-Tech numbers before and after your upcoming timing advance? Curious to see what kind of "free" performance gains this mod will result in. Thanks!
 

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Discussion Starter #14
I'll try. I have to call Sam and see if I can get him to do it for me for free; otherwise, I'll wait until my next oil change and I'm pretty sure I can get my tech to do it while he's at it. At any rate, I need to know in advance when I'm getting it done in order to get in before and after runs which means I can't just pop by and have them do it.
 

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MustGoFastR said:
I'll try. I have to call Sam and see if I can get him to do it for me for free; otherwise, I'll wait until my next oil change and I'm pretty sure I can get my tech to do it while he's at it. At any rate, I need to know in advance when I'm getting it done in order to get in before and after runs which means I can't just pop by and have them do it.
Hey, just schedule an appointment with him to complain about your "bad" gas mileage. :p They'll be happy at that point to hook up the ConsultII unit to check your A/F ratios. Then get the tech to advance the timing. Worked for me at the other dealership.

Hope Sam doesn't catch wind of this scam... :twisted:
 

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Sincity said:
I didn't realize that the inner diameter of the Injen is smaller than stock. With this new info, I wonder if the detriment to the Injen is: 1) Length of tube, 2) Diameter of tube, and 3) Location of MAF sensor.
LIke I predicted in the other post, it turned out to be the diameter of the tubing.

That's simply amazing that Injen wouldn't use the same inner diameter tubing at the point of metering. Since the ECU is tuned to read X amount of air using that stock 3.25" tube, changing the diameter of the tube obviously will throw off the metering capabilities. For part-throttle, closed loop running, this shouldn't be a problem since the ecu has the ability to adjust by using the O2 sensors.

The problem lies when you go WOT, into open-loop (heck, I might be getting the 2 reversed), the ECU defaults to a base WOT map. So now, you're metering air through a smaller tube, the sensor thinks there is X amount airflow, but in reality with the smaller tube, it's less than X. So the fuel being dumped is now much more than is necessary.

As for the other 2 possibilities mentioned, the position of the sensor may be a factor, but that's highly unlikely. Post meter turbulence can throw off the sensor, but in a NA application, it's doubtful there's enough air flowing through the meter for any POST meter turbulence to affect it.

To address the topic of length of tubing, rule of thumb is longer the intake tubing, the more low-end torque is produced. The shorter, the better for high-rpm breathing, so that usually means more HP up top.

Slapping on the $tealin or the JWT should produce more HP since it they attach to the stock MAF meter. But I'd make sure to build some sort of heat shield for them.

I'm happy with the stock airbox design. I don't like the added noise the open cone filter adds. Using a K&N panel filter should give within 1-2 HP compared to a cone filter.
 

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Looking at the numbers again,the 9 degrees of temp may be less significant than the big drop in humidity and that 2 degrees really kicks.
If someone can isolate that (preferably AWD-traction),the diff should show up big!!
 

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I just cancelled the order with Steve at SWAW. He was very gracious about it and said that he has heard of the issues of the Injen for FX. Though I am the first to cancel the order, two more orders have been placed on "hold" from the buyers.
 

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and he wasn't too shocked when i thankd him for giving US the great deal, but then explaining why we had it on hold , and guided him back to our site for an extensive list of reasons (to bad he doesn't offer JWT) and he can't offer a deep discount on Stillen either. / maybe injentech will "visit" us tomorrow and at least offer Dave a refund.
 

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Guys- if you really want to base your decision as to whether or not to go with Injen Technology, based on a $224.99 G-tech Meter as opposed to our $80,000+ AWD in ground DynoJet- the same DynoJet used by NASCAR, then by all means go ahead. Again, don't get me wrong, the g-tech meter is a fun device, and I am in now way knocking the company, but even they state the consistency is hard to maintain with this device.

If the G-tech was accurate, every large manufacturer would cut cost and just use this device to test their products. Still there are too many variables with your testing against our own Injen Test procedure.

The thread mentioned that GeoFX drove his car with the system on and came back with a smile on his face because he enjoyed it- Now isn't that the real point?
 
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