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I will be putting on a HKS exhuast and AEM cold air intake and was wondering if tuning on a dyno would help get the most out of the two. Is it neccasary to tune on a on a dyno for a N/A engine? If so, is it worth the money? Thanks everyone!
 

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I wouldn't worry about it just yet. Of course, if you own the shop then go for it.
 

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Tunning on a N/A car makes a BIG difference over just bolting on the components.Here is a Dyno form Turbo XS with a few minor bolt ons and tuned on the UTEC.More info available here. http://www.racemrc.com/utec.html

Broken BLUE line represnets stock car
Broken YELLOW line represents test pipes,CAI and utec,STOC EXHAUST!
Solid BLUE line represents CAI,TEST PIPES,AND PLENUM..Still STOCK exhaust..

 

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That was the other thing I was trying to think about early this morning. I was thinking that you'd need an external plug-in to help tune the car, which is something most dyno shops do not willingly give out for free. You have to purchase something like the UTEC and have them install it.
 

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I wouldn't wait til FI to tune..

slap on full exhaust, with headers and hf cats.. and take a look at your A/F readings.

Mine were 15.3:1 !!!!!!!!!!! before the ecu flash. Can you imagine running 15.3:1 and not knowing?? talk about rude awakening...
 

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That was the other thing I was trying to think about early this morning. I was thinking that you'd need an external plug-in to help tune the car, which is something most dyno shops do not willingly give out for free. You have to purchase something like the UTEC and have them install it.
The UTEC is fully user tunable with no more than a standard serial port cable and a lap top..Also as awlways maps and software updates are FREE on their website, unlike any other manufacturer or reflash,you always can update mapping for FREE!!
 

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Chris, how did you do the reflash? Did you send it in?
 

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I wouldn't wait til FI to tune..

slap on full exhaust, with headers and hf cats.. and take a look at your A/F readings.

Mine were 15.3:1 !!!!!!!!!!! before the ecu flash. Can you imagine running 15.3:1 and not knowing?? talk about rude awakening...
This is also true..Alot of people dont realize by adding CAI, Exhaust,Headers,test pipes,ect..Your increasing the ability of the engine to breath,which makes the A/F ratio run leaner, as in your case,dangerously lean..Although N/A cars are a bit more forgiving,they will detonate themselves to death with an A/F ratio of 15.3 on 91 octane and aggressive timing such as the timing the Z already runs..At your point a reflash or a method of tuning and adding fuel is a must for safety as well as untapped power and getting the most bang for your buck on your N/A mods. The ECM will not compensate for that lean of an A/F ratio in open loop no matter what you do.It has a set parameter it works off of based on MAF readings that at some point becomes limited in its ability to compensate fuel and timing, at which point knock is inevitable.When knock is detected the ECM will switch into a low octane mapping , robbing you of any power you would have made with your mods.Most people confuse this map switching for the ECM LEARNING MYTH..
 

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I learn something new everyday... :clap:
 

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Smooth & Jinxy,

I was already at AAM getting the work done when we got the 15 a/f readings.

AAM was great! Mike did pull after pull. Taking his time. So we knew it was that lean after slapping the headers on. It's now ~13.3 after 2k or so and solid.

I will note that this was the first time I had gone to AAM and walked away happy. (haha.. drove away...) But I wouldn't mind checking out MRC in NJ.



[edit] The headers were done with everything and also solo, no ypipe or hf cats, or plenum spacer.. We were getting numbers for Strup. This was back in June when nobody else had a dyno for them yet. Also to note the ARC exhaust was already on. I did that a month earlier.
 

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.Although N/A cars are a bit more forgiving,they will detonate themselves to death with an A/F ratio of 15.3 on 91 octane and aggressive timing such as the timing the Z already runs..
Hey man! I only put 94 unleaded in the Z! :irock:

(i understand your Ca. hatin' point) :)
 

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This is also true..Alot of people dont realize by adding CAI, Exhaust,Headers,test pipes,ect..Your increasing the ability of the engine to breath,which makes the A/F ratio run leaner, as in your case,dangerously lean..Although N/A cars are a bit more forgiving,they will detonate themselves to death with an A/F ratio of 15.3 on 91 octane and aggressive timing such as the timing the Z already runs..At your point a reflash or a method of tuning and adding fuel is a must for safety as well as untapped power and getting the most bang for your buck on your N/A mods. The ECM will not compensate for that lean of an A/F ratio in open loop no matter what you do.It has a set parameter it works off of based on MAF readings that at some point becomes limited in its ability to compensate fuel and timing, at which point knock is inevitable.When knock is detected the ECM will switch into a low octane mapping , robbing you of any power you would have made with your mods.Most people confuse this map switching for the ECM LEARNING MYTH..
For what it's worth.....from the Service Manual:

DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION PFP:16600
On Board Diagnosis Logic ABS000W4
With the Air/Fuel Mixture Ratio Self-Learning Control, the actual mixture ratio can be brought closely to the
theoretical mixture ratio based on the mixture ratio feedback signal from the heated oxygen sensors 1. The
ECM calculates the necessary compensation to correct the offset between the actual and the theoretical
ratios.
In case the amount of the compensation value is extremely large (The actual mixture ratio is too lean.), the
ECM judges the condition as the fuel injection system malfunction and light up the MIL (2 trip detection logic).
 

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For what it's worth.....from the Service Manual:

Very interesting. Too bad I don't have video or a picture of it running so lean. From what I've seen so far, the ECM can only compensate so much. I agree with the info you post, but it's hard to deny the cells needing fuel after adding the parts. The ECM may not be perfect after all. :)
 

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To note.. The ECM does not care about power.. It's tuning function to my knowledge revolves around emmisions. Emmisions doesn't care if you make 30 less whp, as long at the O2 sensors are compensating for a clean number.

So, to take Advantage of your newly bought performance parts, the ECU/ECM can be adjusted via Legal OEM software (the same software they use to write the oem data) to make more power. And get your money's worth for all "dem bling bling parts"...
 
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