MAZDASPEED 3 CAI Gains Comparison Depot

[jflash]

the longer you drive the more the mpg goes up. at first it was around 20. now its up to 24(3000 miles). i drive it harder now then when i first got it.

 

[camrycev6]

Well it would have to stop going up at some point.... there is no way it is a linear progression. (Log. maybe...)

Mine was always around 24 BTW. I have been checking the MPG before and after the CAI and nothing really changed in the 2300 miles on the car...

 

[bast525]

just over 1000 mi on mine and I'm averagine like 18 mpg. I know it does tend to go up after the motor breaks in... my SRT was getting like 18ish at first but was getting about 22-23 by the time I traded it in with 16k miles on it.

MS CAI going in this weekend SUHWEEEEEEEEEEEEET!!!!

I hope I get as good results as you guys are... I should really be able to notice the difference right?

 

[Ferdball]

just over 1000 mi on mine and I'm averagine like 18 mpg. I know it does tend to go up after the motor breaks in... my SRT was getting like 18ish at first but was getting about 22-23 by the time I traded it in with 16k miles on it.

MS CAI going in this weekend SUHWEEEEEEEEEEEEET!!!!

I hope I get as good results as you guys are... I should really be able to notice the difference right?

Yup. I did, right after install. Don't forget that you'll hear the turbo and bov a lot more. I thought I had a hose loose.

 

[maczter]

Here are my dyno results. Also on a Dyno Dynamics machine. I hope the size is not too large for this post. Note only mod is MS3 CAI.

What gear was this dyno run done in and was the hood open or closed?

 

[Speedy3]

....I'd also like to know for dyno results submitted in this thread (past and future) if the hood was opened or closed during the dyno runs and which gear the runs were done in. .....

I made it a point when doing my before and after dynos, to do half with the hood open and half with the hood closed. My runs were in 3rd gear, because that is my favorite gear in this car! I just installed brand new plugs. 2 large fans were blowing on the front of the car about 5 feet away. I will post all of them as soon as I get home and get a chance to arrange the graphs. Specific environmental parameters are at the bottom.

I was surprised by the difference in output with the hood closed vs open. I had much higher gains with the hood closed with the MS CAI installed, but very little difference in the stock config.. Here are the peak numbers (btw, most of this data is in the first post in this thread minus the hood open data):

Stock
Hood Open:
HP: 237.49 (@5575),T: 238.60 (@4469)
Hood Closed:
HP: 239.01 (@5575), T: 241.25 (@4325)

Hood Open vs Closed Improvements
0.6% HP gain, 1.1% T gain

With MS CAI
Hood Open:
HP: 248.35 (@5525), T: 259.81 (@4375)
Hood Closed:
HP: 263.23 (@5525), T: 266.06 (@4700)

Hood Open vs Closed Improvements
6.0% HP gain, 2.4% T gain

Overall Gains
Hood Open:
HP: 4.6%, T: 8.9%

Hood Closed:
HP: 10.14%, T: 10.28%

Environmental Parameters

Dynojet Research Dyno on MAZDASPEED 3 in Stock Configuration

• Ambient Temp=64 deg. F
• Atmospheric Pressure=29.80 in-Hg
• Humidity=50%
• Correction Factor=SAE 0.98
• 2 Large Cooling Fans placed 5 ft. from front of car
• Hood Open for 2 runs, Closed for 2 runs
• Runs in 3rd gear only
• Runs started at about 2k RPM and stopped at about 6250 RPM.

Dynojet Research Dyno on MAZDASPEED 3 with MAZDASPEED CAI

• Ambient Temp=63 deg. F
• Atmospheric Pressure=29.90 in-Hg
• Humidity=53%
• Correction Factor=SAE 0.97
• 2 Large Cooling Fans placed 5 ft. from front of car
• Hood Open for 2 runs, Closed for 2 runs
• Runs in 3rd gear only
• Runs started at about 2k RPM and stopped at about 6250 RPM.

 

[dread]

This car should be dyno'd in fifth because that is closest to a 1:1 ratio. Most people dyno in 4th, and avoid third because it is electronically limited.

 

[camrycev6]

Third is not electronically limited from what I read. Only 1st and 2nd are.

 

[desperado-c]

Third is not electronically limited from what I read. Only 1st and 2nd are.

My boost gauge says otherwise. In 3rd I don't get more than 14 psi after the initial spike even on the steepest hills. Also, there's throttle reduction in gears 1-4 per testing done by AMS and CPE, IIRC.

Speedy, why 3rd anyway? It's a 6 speed.

 

[gsrtype1]

thanks for the dyno thread 3 GEAR EXACTLY, you don't get full power till 3rd, Automobile magazine came up with 216hp but they averaged the gears, 1st and 2nd you only getiing 72% to 89 percent power!

 

[camrycev6]

Again, I don't know about what the boost guages are saying, but multiple magazines and the dealers all say the same thing. 1st / 2nd are limited, but not third.

 

[bast525]

hmmm I seem to remember Automobile mag saying 3rd was limited as well to like 92%

At any rate, with EVERY turbo car I've owned (MS3 being my fourth), you will see more boost in higher gears. Even on older turbo cars that use NO computer controlled boost. Even on the SRT when I took the computer out of the loop by installing a manual boost controller

Higher gear = higher load = more boost

I have seen this on every turbocharged car I've owned. On average, the cars would all boost .5-1 more psi of boost in each higher gear.

SRT-4 with manual boost controller for example... would only peak 13psi in first gear, but in 5th it would peak 17-18psi. Again, with absolutely NO computer control. Just boost line from the turbo, run through the MBC, directly to the wastegate actuator.

 

[jflash]

that could explain why my stock dyno was quite a bit higher than the others here. my runs were in 5th. its closest to 1:1.

 

[desperado-c]

hmmm I seem to remember Automobile mag saying 3rd was limited as well to like 92%

At any rate, with EVERY turbo car I've owned (MS3 being my fourth), you will see more boost in higher gears. Even on older turbo cars that use NO computer controlled boost. Even on the SRT when I took the computer out of the loop by installing a manual boost controller

Higher gear = higher load = more boost

I have seen this on every turbocharged car I've owned. On average, the cars would all boost .5-1 more psi of boost in each higher gear.

SRT-4 with manual boost controller for example... would only peak 13psi in first gear, but in 5th it would peak 17-18psi. Again, with absolutely NO computer control. Just boost line from the turbo, run through the MBC, directly to the wastegate actuator.

Definitely load-based. That's why I ran it up some really steep hills in 3rd, to see whether under the higher engine load it would run up to the 5th/6th gear max of approx. 16 psi on the flats. Totally unscientific, but it doesn't seem to want to settle on anything higher than 14 psi in 3rd. 4th also seems lower than 16 psi, but it's harder to find a steep hill I can run in 4th for any length of time.

 

[maczter]

Interesting.

So now we know that keeping the hood closed (as long as fans are going) does, in fact, produce more power (as suspected).

I guess now we just need to figure out which gear is truly closest to 1:1. 5th or 6th?

 

[jflash]

5th is 1.09:1
6th is .85:1

the dyno operator told me he wouldnt be able to do a 6th gear run as it would cut out before redline.

 

[maczter]

5th is 1.09:1
6th is .85:1

the dyno operator told me he wouldnt be able to do a 6th gear run as it would cut out before redline.

good point. thanks!

 

[camrycev6]

hmmm I seem to remember Automobile mag saying 3rd was limited as well to like 92%

At any rate, with EVERY turbo car I've owned (MS3 being my fourth), you will see more boost in higher gears. Even on older turbo cars that use NO computer controlled boost. Even on the SRT when I took the computer out of the loop by installing a manual boost controller

Higher gear = higher load = more boost

I have seen this on every turbocharged car I've owned. On average, the cars would all boost .5-1 more psi of boost in each higher gear.

SRT-4 with manual boost controller for example... would only peak 13psi in first gear, but in 5th it would peak 17-18psi. Again, with absolutely NO computer control. Just boost line from the turbo, run through the MBC, directly to the wastegate actuator.

Motortrend, Nov 2006 - "....Launching the Mazda, on the other hand, required a low-RPM dop of around 1000 rpm and, because the torque-management system cuts torque under full throttle in first and second gears, short-shifting at 6000."

Automobile, Nov 2006 - "In first, you're allowed 72 to 79 percent of the maximum torque (depending on steering angle. In second, your allowed 77 to 92 percent. The full load comes through in third through sixth gears."

I think this takes care of this one. 1st and 2nd limited torque...3rd and up you have it all.

 

[bast525]

Motortrend, Nov 2006 - "....Launching the Mazda, on the other hand, required a low-RPM dop of around 1000 rpm and, because the torque-management system cuts torque under full throttle in first and second gears, short-shifting at 6000."

Automobile, Nov 2006 - "In first, you're allowed 72 to 79 percent of the maximum torque (depending on steering angle. In second, your allowed 77 to 92 percent. The full load comes through in third through sixth gears."

I think this takes care of this one. 1st and 2nd limited torque...3rd and up you have it all.

I wasn't arguing it, just said I thought I remember that. I do remember reading SOMEWHERE (maybe SCC?) about limiting in third as well. But that wasn't my point. My point was in reply to someone saying they saw less boost in 3rd than in 4th and up. And I was saying, this is normal. I've seen this on ALL turbocharged cars, whether they had a computer controlling the boost levels, or a simple ball-and-spring valve set manually with no computer control. I ALWAYS see higher boost in higher gears.

 

[Speedy3]

Interesting.

So now we know that keeping the hood closed (as long as fans are going) does, in fact, produce more power (as suspected).

I guess now we just need to figure out which gear is truly closest to 1:1. 5th or 6th?

None. I used OBDII data and Auterra DynoScan SW to determine the gear ratios for each gear between the crankshaft and the tires. Here are the results:

1st Gear: 14.384
2nd Gear:9.060
3rd Gear: 6.173
4th Gear: 4.731
5th Gear: 3.730
6th Gear: 2.930

This is as accurate as you can get, based my tires. More tire wear, the lower the number. My tires had about 4K miles on them when I measured this.