[Jay24]

Got a chance to do some vag-com logs with the stock airbox vs EVO CAI today. The colors got a little muddled converting to gif. Orange and black are for the EVO. Blue (purple?) and red are for stock airbox.
1st graph is air mass readings in g/s. 2nd graph is temperature logs at the manifold in celcius. You'll also need to resize the image to "Normal" to read it. Sorry.
http://community.webshots.com/album/26030231dxHQKamQMa
Conditions during stock runs
*Time: 9:00AM-10:30AM
*Ambient temp: 42 degrees F
*Windchill: 39 degrees F
*Barometer: 30.40 and falling
*Humidity: 93%
*Winds: NE 6mph
Conditions during EVO CAI runs:
*Time: 12:00AM-1:15AM
*Ambient temp: 49 degrees F
*Windchill: 45 degrees F
*Barometer: 29.79 and falling
*Humidity: 90%
*Wind: W 10mph
Also intake manifold temps at idle after a 10 minute cool-down after the runs were 39 degrees Celcius for stock and 42 degrees Celcius for the EVO. Hood was closed in both instances for the entire duration. Runs were made 10 minutes after the car had reached normal operating temperature. Runs were done on the exact same stretch of road WOT from ~2K to redline in 3rd.
Also I haven't done any block 120's for the EVO yet, but I'll do some tomorrow and see if I can get the 7-8 hp improvement some others have. Although looking at these results, I don't see how that'll happen.

[Modified by Jay24, 12:50 AM 2-11-2002]

 

[John A]

Re: Before/after runs w/ EVO CAI (Jay24)

great graphs... bummer to see that CAI isn't doing more... since people are always like 'it only works out on the road, not on a dyno' it would have been great to see something like this come out and have it kicking the crap out of stock...

 

[Jman5000]

Re: Before/after runs w/ EVO CAI (Jay24)

3 degrees for this kind of testing under those conditions basically shows nothing.
Like 1-3hp differences on the dyno. It's too close to call anything definitive.

 

[santa's 1.8T]

Re: Before/after runs w/ EVO CAI (Jman5000)

a dyno will not show much (if any) hp gain for an intake...however, people do swear that it makes more of a difference when air is being rammed down the intake pipe on the road. I personally think that if you buy an intake, you should buy it for looks and sound...any performance improvement will be a bonus.

 

[Jman5000]

Re: Before/after runs w/ EVO CAI (santa's 1.8T)

I bought mine to combat heat soak. And when I felt the throttle response...that's what I thought "bonus".

 

[Roy1.8T]

Re: Before/after runs w/ EVO CAI (wolfsburg_de)

Hmm...that's what I'm thinking...basically no gains. In fact, the stock air box temperature was way lower...??
Weird. I heard good things from my friends who have it. I guess AEM was right...the stock air box is extremely good...

Roy

 

[John A]

Re: Before/after runs w/ EVO CAI (Jman5000)

wow, since there's no decrease in intake temps, and no increase in air mass, i'm surprised that it made a difference in throttole response or the amount of heat being taken in...

 

[Jay24]

Re: Before/after runs w/ EVO CAI (John A)

First off, thanks for the compliments everyone.
And yeah. I think it's been shown numerous times on this forum, as well as on audiworld, that the stock airbox and even the oem filter are very good. Also in some of the other discussions on the merit of CAI's for our cars, a few people pointed out that although you might see measurable gains with a CAI before the turbo, those gains will probably disappear once that air passes through the turbo, IC, and stock intake piping. And at least going by this data, maybe they were right?

 

[dbrowne1]

Re: Before/after runs w/ EVO CAI (Jay24)

My block 120 dynos showed a 12hp/10ft-lb peak difference which began to develop only after 5K rpms. I posted the data and charts here a while back. I didn't log airmass (because the stock MAF is so unreliable) or temps.

 

[Jay24]

Re: Before/after runs w/ EVO CAI (dbrowne1)

quote:[HR][/HR]My block 120 dynos showed a 12hp/10ft-lb peak difference which began to develop only after 5K rpms. I posted the data and charts here a while back. I didn't log airmass (because the stock MAF is so unreliable) or temps.[HR][/HR]​

dbrowne1,
I read that. As a matter of fact, it was a huge part of the reason I went with the EVO in the 1st place.

Anyway the only question I have about your comment is the part about the MAF being so unreliable. When the ECU calculates load, doesn't it use info from the MAF? If so, I don't see how your block 120's would be anymore accurate than my block 002's.

 

[Roy1.8T]

Re: Before/after runs w/ EVO CAI (Jay24)

true, true...
At any rate, ignoring the air mass for now, what about the intake temps?!? That sounds messed...you'd think for SURE that the Evo would be colder, but it's not by a long shot...
Any ideas why?

Roy

 

[John A]

Re: Before/after runs w/ EVO CAI (Roy1.8T)

the intake temp thing was wild, i passed that around to a few people who were all excited about getting CAI's

 

[undrpressr]

Re: Before/after runs w/ EVO CAI (John A)

But both the EVO hp and tq graphs shows much better throttle response-- when the stock airbox is making 125 lb/ft, the EVO is making about 185 lb/ft. Pretty good difference if you ask me!

 

[Jay24]

Re: Before/after runs w/ EVO CAI (wolfsburg_de)

Hrm... You people are fast. I JUST finished posting those new graphs up.

Anyway couple of comments. I did some logs last night. Basically a few block 120s and one block 006 for temp. Results were VERY interesting. First of all, here were the conditions:
Ambient temp: 30 degrees Celcius
Wind chill: 26 degrees Celcius
Barometer: 30.21 and falling
Humidity: 48%
Winds: 3mph N
Anyway if you look at the graph titled "evo_temp" and the curve "EVO2 (AT: 30F)", you can see how much difference the cold air made. Also manifold temp after idling the car for 10 minutes after the runs (hood closed the entire time) was 30 degrees Celcius- BIG improvement from the previous day of 39 stock and 42 w/ the EVO. Seems the colder the ambient temp, the better the EVO CAI performs. In all fairness though, I don't know how the stock airbox would do under these conditions. At least when it comes to block 006's.
I DO know however that peak torque as measured by the vag-com improved with the EVO on that night (see: "evo_torque"). It was marginal at best, but unequivocal. I've run on colder nights than last night with the stock airbox, and the best I've ever logged was 301.8 Nm or ~222.72 lb-ft torque. Last night however peak torque came in between 303.8 Nm (224.2 lb-ft) and 305.8 (225.68 lb-ft) for all 3 runs. Unfortunately though it's debatable whether the EVO made ANY sort of difference in terms of area under the curve.
Also I did some runs this afternoon with the driver-side front fender liner removed. My thinking was maybe improving airflow to the filter would improve results. BIG MISTAKE. As you can see from all 3 graphs (evo_temp, evo_hp, evo_torque), removing the fenderliner was horrible for performance. The one graph I didn't bother to post for the mass air measurements also showed a big drop in flow w/ losses across the board and a 12 g/s drop at peak.

Oh and here's the conditions for those runs:
Ambient temp: 43
Wind chill: 34
Barometer: 30.01 and falling
Humidity: 31%
Winds: 23mph S


[Modified by Jay24, 2:05 PM 2-12-2002]

 

[Dub_PRIME]

Re: Before/after runs w/ EVO CAI (Jay24)

Since the stcok airbox is very good, has anyone thought of just putting a good ceramic coated aluminum pipe from the stock air box to the intake?? or any other type of heat sheilded material that is smooth on the inside.


[Modified by Dub_PRIME, 10:03 PM 2-12-2002]

 

[dbrowne1]

Re: Before/after runs w/ EVO CAI (Jay24)

quote:[HR][/HR]
I read that. As a matter of fact, it was a huge part of the reason I went with the EVO in the 1st place.

Anyway the only question I have about your comment is the part about the MAF being so unreliable. When the ECU calculates load, doesn't it use info from the MAF? If so, I don't see how your block 120's would be anymore accurate than my block 002's. [HR][/HR]​

Yes, hence the reason that I take block 120 dynos with a grain of salt. The ones I did were pretty smooth and clear though, and CLEARLY showed perfectly identical curves until 5K rpm, followed by a clearly distinguishable increase for the CAI. Mine will be more valuable as a tool to assess the effect of the CAI if my MAF is functioning properly and yours isn't. Otherwise, you're right. Mine are no better, and I wasn't suggesting that. Just pointing out the inconsistency in our results.

 

[RVs021.8T]

Re: Before/after runs w/ EVO CAI (Dub_PRIME)

quote:[HR][/HR]Since the stcok airbox is very good, has anyone thought of just putting a good ceramic coated aluminum pipe from the stock air box to the intake?? or any other type of heat sheilded material that is smooth on the inside.

[Modified by Dub_PRIME, 10:03 PM 2-12-2002][HR][/HR]​

Lots of people have done something like that. They keep the stock airbox and run some piping down to the fender or grill. See http://www.watercooledvw.com if you are interested in doing it.

 

[AxeAngel]

Re: Before/after runs w/ EVO CAI (RVs021.8T)

good testing, i did some similar testing and also showed no gains...

with stock airbox and bmc cda