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Discussion Starter · #1 ·
We have received several inquiries as to whether or not we were going to develop a calibration that is compatible with this particular intake system. Our test results demonstrate that the standard AccessPORT calibrations are compatible with the SPT intake system on the 2004-2006 STi. We felt it necessary to do what we could to educate the end users about the affects of running a vehicle with the SPT intake system for the 2004-2006 STi. I hope you find the readings informative. The file is a little a large so I could not post it in this thread so here is a link = http://www.cobbtuning.com/tech/instructions/SPTIntakeWRXSTiv1.00.pdf

I would be happy to field any questions or concerns you have concerning our testing procedures, test results, etc.

Take care,
Christian.
 

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Interesting to see the results, thanks for all the work and testing done!

Side Note: ... I realize that your saying a short-ram intake absorbs more heat then the stock airbox because of the engine bay temperatures. My question is why wouldn't Cobb offer a cold air feeding intake, but instead a short-ram similar to the SPT model.
 

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Christian, Thank you VERY much for providing this test & data. It will end several arguments on this board. I have this intake and was able to lower the intake temp by slightly modifying the heat sheild & leaving the snorkle & silencer in place which directs cooler (while moving) air into the sheilded part of the engine compartment.

Thanks again
 

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Discussion Starter · #5 ·
RBMike said:
Christian, Thank you VERY much for providing this test & data. It will end several arguments on this board. I have this intake and was able to lower the intake temp by slightly modifying the heat sheild & leaving the snorkle & silencer in place which directs cooler (while moving) air into the sheilded part of the engine compartment. Thanks again
No problem, how did you get the snorkle to fit. The instructions say to leave it off and when I tried to install it, the snorkle contacted the intake piping?

Christian.
 

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Wow. Great job on the testing! Very good read. :)
 

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Nice work!

I only have one small change to that document. The document says ...

"As you can see the ignition advance is calibrated to be decreased starting 140 degrees Fahrenheit (F), "

I don't believe this is true. The ECU interpolates between the 122 and the 140 point. Thus, the ECU actually starts pulling timing directly after 122 and slowly pulls more and more until it reaches the value specified at 140.

t
 

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WolfPlayer said:
Nice work!

I only have one small change to that document. The document says ...

"As you can see the ignition advance is calibrated to be decreased starting 140 degrees Fahrenheit (F), "

I don't believe this is true. The ECU interpolates between the 122 and the 140 point. Thus, the ECU actually starts pulling timing directly after 122 and slowly pulls more and more until it reaches the value specified at 140.

t
nhluhr said:
One technical note in the section about Timing adjustment for intake air temp: due to interpolation in the table, the timing actually starts to get pulled at any temperature above 122 - in the case of the stock calibration as shown in the pdf, that is roughly a half degree pulled for every degree over 122.
do you guys share the same brain? ;)

good thinking. makes sense.
 

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Christian. said:
No problem, how did you get the snorkle to fit. The instructions say to leave it off and when I tried to install it, the snorkle contacted the intake piping?
They touch, but there is enough flexibility in the snorkle and the intake mount to shove it in there. I notice that the plastic snorkle has deformed a bit to fit around it, I assume it softened from the heat of the aluminum.
 

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Excellent research!

Thank you Christian for the facts and figures. Some of us opted for the SPT simply for warranty/unfriendly dealer situations.

Now, a question to be researched - does that $70 SPT heatshield bought make any difference :lol:

I just ordered a 2006 WRX foglamp bezel/cover and I'm fabbing up the dryer hose cold air ram into the engine compartment now. In the meantime, I reconnected the factory snorkle and front mini-scoop with no interference to the SPT intake.

Again, thanks to COBB for stepping up to the plate and putting this issue to rest.

Mitch
 

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Christian. said:
No problem, how did you get the snorkle to fit. The instructions say to leave it off and when I tried to install it, the snorkle contacted the intake piping?

Christian.
I left all the mounting hardware loose (except the intake hose clamps) and pushed the intake back as far as I could (away from the front of the car). Then tightened it all up while holding it. I also put a slight bend in the front most part of the heat sheild as it was contacting the bottom of the middle of the snorkle. I then placed a calibrated thermol couple 1/2 inch from the surface of the rear face of the cone filter (hot side) and measured the air temps there while driving. My set up measured consistantly about 7 deg F above that of what the dash outside temp was (ambient) at speeds above 25 mph.

http://i8.photobucket.com/albums/a43/RBMike/e219d9d5.jpg
http://i8.photobucket.com/albums/a43/RBMike/e219d9d5.jpg
http://i8.photobucket.com/albums/a43/RBMike/Picture053.jpg
 

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A little home depot motorsports ducting and the heatshield should make it perform like the stock system in terms of IAT. My highway cruise temps with my typhoon/shielding/ducting show lower IAT then the stock readings b/c the fresh air from the fogs make a huge difference. Only issues I have come in contact with is if you place the duct right by the filter(under) when it rains there is a chance that some some specs of water may come in contact with the filter and skew your fuel trims. Great work though, I am glad Cobb is finally back in the game with articles/testing/development. Nice to finally see that some new products coming out even though they are taking a little longer than expected ;) Looking foward to the new features and hopefully sooner than later :D (cough - launch control)
 

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crystal_Imprezav said:
Only issues I have come in contact with is if you place the duct right by the filter(under) when it rains there is a chance that some some specs of water may come in contact with the filter
This is what I was thinking about when I decided to leave in the snorkle & silencer instead of new ducting.
 

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ya to make the snorkle fit back in, you basically gotta force it in and it DOES fit after about 5 min of manuvering stuff. at first i thought it wouldnt fit but it does
 

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Anyone else notice that the AFRs seem to be leaner under WOT with the SPT intake or am I reading things incorrectly?
 
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