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Basic Engine Tuning

Old 08-29-2003, 06:02 PM
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Originally Posted by Fish' date='Aug 29 2003, 11:26 AM
I now the bit about running lean and det, but the same person told me that if I was running to rich, I could also get det!



Is this correct or are they talking crap?



Dan
they are prolly right, i read a really good article a couple weeks ago, i wish i could find it. bascially detonation is a chemical reaction, that needs lots of heat



mike
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Old 08-30-2003, 01:20 PM
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Thanks for the info guys.

Mike let me get throuigh all those links and then I'll be back with some more questions Im sure.



Turborotor, can we get a pin please.

D.
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Old 08-30-2003, 01:25 PM
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So if 14.7:1 is stochiometric then my car being tunned 11:1.

It's quite a bit more rich than stock maps.(i assume that stock maps are supposed to be tuned to stochiometric?) I'm starting to make sense of it.
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Old 08-30-2003, 04:56 PM
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I'll throw in a few things i learned



timing should be retarded the most at the peak tourqe and can be raised again after peak torque to keep the egt temps stable.Also find out what the safe egt temps are for a fd...for idle/cruise and wot.



about tuning timing with a egt...lets say at idle your a/f is 13.5-14.7 and your egt temps are a bit high.because the fuel is set at a reasonable mixture at idle,you dont want it any richer,you would keep a eye on knock and raise the timing at that rpm point to lower the egt temps,i dont see someone having a/f of 11.5 at idle..theres only so much fuel you can dump in,into a engine.so set the fuel,then timing and always keep a eye on KNOCK!!



most ppl put egt in the exhaust manifold and if got someone elses map id look it over first and compare it..Also use the powerfc boost controller to raise the boost a few psi at a time to tune and dont just hit it at 15psi or w/e..im learning alot myself because i have noone at all to help me tune my car...



Hope we keep this thread going...
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Old 08-30-2003, 07:08 PM
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Air:fuel ratios fluctuate depending on load, boost, rpm, tuning, etc. Mazda may have tuned for a near 14.7:1 at idle but I think they are around 9.5:1 or 10.5:1 under full load in stock form.



I've only seen a few runs on the dyno with stock cars and wide band air:fuel meters hooked up.
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Old 08-30-2003, 07:18 PM
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How does a wide band display info?

Does it tell you the exact afr?
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Old 08-30-2003, 11:43 PM
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Yes.



Let me re-state. Exact to within whatever margin of error the wide band is calibrated for I would imagine.
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Old 08-31-2003, 11:56 AM
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Originally Posted by Mazderati' date='Aug 30 2003, 07:43 PM
Yes.



Let me re-state. Exact to within whatever margin of error the wide band is calibrated for I would imagine.
It displays voltage correct? i.e. 4volts = 14.7:1 stoch.

You need to know the conversion as I understand it.

Is there a site that has that chart?
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Old 09-01-2003, 01:59 PM
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Where did everyone go?
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Old 09-01-2003, 02:53 PM
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heres a map of the stock ecu tuning zones







in the light load and idle zones the ecu is gonna run in the 13's as far as afr

in the feed back zone its gonna run off the 02 sensor, so its gonna be 14.7:1 +/- .4



in all the others it runs 9-10's to be safe



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