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Discussion Starter #1
i have a lil 89 fox with a procharger pushing about 6 psi and a holley systemax top end its been running rich for a few weeks now and i cant solve it i have done a tune up new o2s ajusted the tps put a ajustable fpr wich is set at about 39 psi w/o vaccume line on my maf is set to my injectors and there is no vaccume leaks anywhere i dont know what else it could be any help / ideas would be greatly appreciated:eek:
 

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what size injectors do u have?? have u had the car chipped/tuned
 

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Is it stalling or idling rough as well? Some people have issues with injectors larger than 30# without a custom chip or reprogram. Maybe you can try a lower FP for a while. Just don't go lean on the top end ;)
 

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Is it stalling or idling rough as well? Some people have issues with injectors larger than 30# without a custom chip or reprogram. Maybe you can try a lower FP for a while. Just don't go lean on the top end ;)
+1 6psi=stock fuel system+fmu or 24lb'ers with cal'd maf. 36 is overkill, but I think it should be fine like said with a tune. Still would explain alot if your maf wasn't cal'd to the 36's. Also, other sensors can cause your 02's to make your car run rich. Try running codes.
 

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no chip ... and the injectors are 36pound
u need your computer chipped and tuned cause the computer cant handle over 30lb injectors i have 38lb on my 347 and i havnt had it tuned yet but i will very soon.. since our computers cannot be flashed they must be chipped to shorten the injector pulse.. try to turn your fuel pressure down to 36 before vacuume. and then with the car off make sure u are getting exactly .98 volts to the tps sensor with the green/? wire being the positive. if its not try to loosen it and turn it counter closkwise.. if its close turn the idle screw down to get it there if its way off u can drill the holes a lil to get it to turn where its needed..
 

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He said the MAF is cal'd, at least I think thats what he was getting at. Isn't there something with the injector pulse width with a stock computer and big injectors like that? Like sean was probably getting at with the question about the chip.

I agree, we need more info.

edit wow.. I take a long time to type haha I started typing before sean posted.. 8 mins later I post this, haha thats what I get for watching tv and playing on the internet
 

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He said the MAF is cal'd, at least I think thats what he was getting at. Isn't there something with the injector pulse width with a stock computer and big injectors like that? Like sean was probably getting at with the question about the chip.

I agree, we need more info.

edit wow.. I take a long time to type haha I started typing before sean posted.. 8 mins later I post this, haha thats what I get for watching tv and playing on the internet
u were catching some of my thoughts as i was typing
 

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Imma shutup and listen on this one, I don't own a supercharger so will never know how it works. I can never afford 5 grand to drop a paxton in mine.
 

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Discussion Starter #12
coll guys thanks ...
the maf is calibrated to the injectors but i didnt know that anything bigger than 30lbs injectors needed to be chiped ...
anybody know of a good chip brand to get or would i benifit more from down sizing the injectors
cuz i know there over kill for what i have the car set up to do ... :cool:
 
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