Frustrating dyno day, need some help
10-08-2004, 06:14 PM
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Frustrating dyno day, need some help I posted this also on ls1gto and ls1tuning but just want to make sure I get a big audience and help. ( we all know they are on here 
)
Ok went to the dyno after getting a magnacharger on and trying to improve hp/tq.
Started out normal to get afr and base numbers - base was TERRIBLE for a s/c ls1.
Like 254 rwhp with 320 rwtq afr was running in the 14s.
So we proceeded to get the afr down first so we could add timing later.
decreased IFR 10% and AFR went UP to 15s. weird huh.
increased IFR 10% and AFR dropped to 13.5
increased IFR 20% and AFR dropped to 13.3 INDC was no more then 50%.
increased IFR 30% and AFR ROSE to 13.5 indc same at 50% so we dropped the ifr back to 20% and increased the MAF 10% this dropped us down to 13 AFR, increasing the MAF anymore actually leaned it out more same 20% and 30% actually was showing AFR 17-19s and obviously knocking like hell. So MAF back to 10% and we were once again at 13.
Next PE increased 10% and POOF 12.5. And all was good
So now we added timing in the cell 22 range, it was at 16,17,18,19 from 2200 at .72 to 20, magnuson said no more then 22-23 for timing in this range so 20 seemed more but safer.
Well this run once again it mind went nutz and AFR at 19 knocking like mad. NO fuel changes at all.
Putting the tune just before the timing change back on that just one run early showed 12.5 AFR now showed 15????
So any quesses? DYNO messed up or at least the o2 sensors messed up at the dyno?
Major frustration, one step forward and two back.
[edit] forgot to add[/edit]
rwhp was at 308 rwhp ( only 100 short ) and 378rwtq. These numbers just did not make sense. Oh its a mustang dyno so roughly 330rwhp(way low should be around 390-425) and 420rwtq( which is what it should be doing)
)Ok went to the dyno after getting a magnacharger on and trying to improve hp/tq.
Started out normal to get afr and base numbers - base was TERRIBLE for a s/c ls1.
Like 254 rwhp with 320 rwtq afr was running in the 14s.
So we proceeded to get the afr down first so we could add timing later.
decreased IFR 10% and AFR went UP to 15s. weird huh.
increased IFR 10% and AFR dropped to 13.5
increased IFR 20% and AFR dropped to 13.3 INDC was no more then 50%.
increased IFR 30% and AFR ROSE to 13.5 indc same at 50% so we dropped the ifr back to 20% and increased the MAF 10% this dropped us down to 13 AFR, increasing the MAF anymore actually leaned it out more same 20% and 30% actually was showing AFR 17-19s and obviously knocking like hell. So MAF back to 10% and we were once again at 13.
Next PE increased 10% and POOF 12.5. And all was good
So now we added timing in the cell 22 range, it was at 16,17,18,19 from 2200 at .72 to 20, magnuson said no more then 22-23 for timing in this range so 20 seemed more but safer.
Well this run once again it mind went nutz and AFR at 19 knocking like mad. NO fuel changes at all.
Putting the tune just before the timing change back on that just one run early showed 12.5 AFR now showed 15????
So any quesses? DYNO messed up or at least the o2 sensors messed up at the dyno?
Major frustration, one step forward and two back.
[edit] forgot to add[/edit]
rwhp was at 308 rwhp ( only 100 short ) and 378rwtq. These numbers just did not make sense. Oh its a mustang dyno so roughly 330rwhp(way low should be around 390-425) and 420rwtq( which is what it should be doing)
