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Old 08-02-2007, 01:50 PM   #1
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Default Bigger Injectors??

2000SilverBullet wrote:
My big end this year was 17-18 mph compared to 20-21 mph last year. That'* not the same.
5 mph is significant.
Last year was with a 3.0 pulley and Gen3 and this year was 3.2 pulley and GenV.

The WOT A/F mixture shows on my wideband as 10.9:1 and I don't see any KR with WOT timing at 19*

Rogue replied:
Your right I was looking at the wrong side of the slip. Are you still running stock injectors? Have you scanned injectors duty cycle?
Even tho the A/F mixture seems rich, I have noticed KR when applying low speed load. Seems like the fuel does not react soon enough. If I let up a little the KR disappears, then I can get back into it without any KR.
If I manually downshift, I do not get KR.
If I punch it from 30 mph and it downshifts, I get KR...
WOT from a stop, I get NO KR.

I have an Aeroforce gauge. What do I look for to determin duty cycle? What should it be?
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Old 08-02-2007, 04:48 PM   #2
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Check your Injector Pulse Widths. Duty cycle is a forumla of rpm vs pulswidth and can be calculated as

rpm times IPW divided by 1200 equals IDC in percent

so 6000rpm and 22 ms pulsewidths would be ((6000 * 22) / 1200) or 110%
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Old 08-03-2007, 11:58 AM   #3
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80 to 85% is generaly considered the limit on injector duty cycle.
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