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hey gurls n gurls, i need sum help

i put my car on the dyno about 4 months ago at unigroup. it made 181.5 kw as seen by the printout. as you can see, the afr remains at 14 until 5500 rpm and then drops to 13 by 6000rpm and then to 12 by 6500 and onwards. Back then i had cat back exhuast, pod, front mount and close to 1 bar of boost.

Now i have a split dump/front pipe, high flow cat, fuel pump. last week i installed a power fc and got it tuned by hit man. As you can see it only made 175 kws? i was like wtf? he reckons sumthings really faarked cos it shud be closer to 190-200rwks. he recons maybe my cats melted cos my pump died and i was running really lean, however if u look at my afr now theyre really low...max is 12.5 but it drops away significantly.

i dunno, do u think i shud increase my afr to what it was before. cos even though it was 14, it dropped to 12 on high load and im thinking maybe thats safe?

newways my power is low and boost comes on slowly sumtimes, yet mid-range is now better? on low throttle, if i hold it at a certain point, i get this slight detontation. i dunno, any suggestions?

both graphs are there

cheers, anton

post-29367-1161416292.jpg

post-29367-1161416442.jpg

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the closer you get to 10:1 afr, the safer it gets

the reason it may have become richer is because of the extra airflow caused by the dump and cat, combined with the added fuel flow of the aftermarket pump.

What you get is a richer mixture causing less power (cos before you were lean)

someone please explain this better than me...

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just noticed your intake temp was 54 degrees. that may have something to do with it.

also i'd say your tune isn't the best. the graph is a bit crappy, but that could also be due to the fact you are losing quite a bit of boost.

and if it was run in 4th gear, they are backing off at about 6000rpm.

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