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Old 07-20-2007 | 10:50 PM
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Default A/F READINGS

Well I am just about there. How does this sound. From 3500-5000 I am at 10.8-11.9. Once I get over 5000, I am about 12.00-12.3. after 5500 to about 6000. I go from 12.2-12.7. 12.7 is close to 6000. I have imagine auto fuel head mods and brian leasks WUR and soliniod. I have a smooth idle with A/F at 13.8-14.00. I would like to richen it up over 5500. I dont think I can go any further with the WUR full throttle inrichment adjustment. I have it just about all the way out. Should I richen it up with the fuel head. How bad it 12.7 up top. I have great cooling. The Temperature gauge in 90 deg is just below the first line on the temp gauge. I was told that is 180-190. I am getting my A/F readings from my Innovative wide band. The O2 sensor is mounted about 3-4" after the muffler. I have a full GHL exhaust, headers to single out muffler. I do not hear any detonation at all. I dont go above 6000 and motor pulls great.
Thanks John
Old 07-21-2007 | 03:29 AM
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Do you know at what RPM your solenoid is set too ?
Old 07-21-2007 | 09:26 AM
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I have it set at 4800rpms.
Old 07-21-2007 | 12:35 PM
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You could always try installing a lower RPM "chip" and see if the entire upper AFR curve will shift by having enrichment come on sooner. I think I'm running the 4,400. I'm just a tad rich, though. I'd like to be in like 12.0 or 12.2 for my over 5,000 RPM full boost. Right now, I'm like 11.5. I guess for fear of not knowing 100% accuracy of these wideband sensors, I prefer to be a tad rich.
Old 07-21-2007 | 05:36 PM
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I have tried the lower chip(4200).I have 4800 in there. It did not seam to make a difference. I am going to recalibarate my 02 sensor and see if i am getting accurate readings.
Old 07-21-2007 | 09:53 PM
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I don't know the Brian mod at all. However, I had an adjustable WUR that I could tune all the way to redline (about 6500) and could keep the AFR at 12.2 max. Do you know how to adjust your WUR? Also, where does your motor create max HP?
Old 07-22-2007 | 01:24 PM
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DonE, My motor is a 3.5 with sc cams. So I am assumming my max power is between 5000-6000. To adjust my WUR full fuel inrichment I was told that you adjust the large disc on the bottom of the WUR. The more you bring it out the more fuel on fuel trottle. Am I wrong.
Thanks John
Old 07-22-2007 | 01:30 PM
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Originally Posted by JBrown
DonE, My motor is a 3.5 with sc cams. So I am assumming my max power is between 5000-6000. To adjust my WUR full fuel inrichment I was told that you adjust the large disc on the bottom of the WUR. The more you bring it out the more fuel on fuel trottle. Am I wrong.
Thanks John
On the bottom of the WUR there is an "enrichment thresh hold" adjustment. These are the three screws around the circular disc. I think these adjust the spring/diaphram for the enrichment circuit. This is one area that I haven't messed with yet, so I'd read Brian's manual carefully. But I think there is still yet some adjustability for you.
Old 07-22-2007 | 10:22 PM
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Two things - don't go above 6000 rpm or learn to tune the WUR. Once its adjusted, you can forget about it for the most part. You need fuel pressure guages for Bosch systems and a wideband O2. If your interested in an explanation, PM me. Its not difficult at all - just time consuming

Good luck.
Old 07-22-2007 | 10:23 PM
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Well I took out the set screws and no difference. It does not make a differece if I change out the rpm chips or take out the three screws around the circular disc. I find it hard to believe I cant get more fuel up top. I am only running 12lbs of boost too.
Old 07-25-2007 | 02:51 PM
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I found my problem. The MSD box was triggering the soliniod to stop my inrichment but did not turn it back on (was not reading tach signal). The MSD box has a loop on it for what kind of ignition system you have and I had to cut the loop. Once I cut the loop I was good to go. Now I have to much fuel. I will also tell you, I will not buy anything from a company that does not have a phone number. I have emailed Brian and asked him to call me on the phone. You can only do so much emailing back and forth. I got no call. I would like to thank DonE for his help. He spent almost an hour on the phone discussing how the WUR works and he did not even do the modification. Thanks again for the help.
Thanks John
Old 07-25-2007 | 03:45 PM
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Originally Posted by JBrown
I found my problem. The MSD box was triggering the soliniod to stop my inrichment but did not turn it back on (was not reading tach signal). The MSD box has a loop on it for what kind of ignition system you have and I had to cut the loop. Once I cut the loop I was good to go. Now I have to much fuel. I will also tell you, I will not buy anything from a company that does not have a phone number. I have emailed Brian and asked him to call me on the phone. You can only do so much emailing back and forth. I got no call. I would like to thank DonE for his help. He spent almost an hour on the phone discussing how the WUR works and he did not even do the modification. Thanks again for the help.
Thanks John
John I checked the MSD manual again, and it clearly states if you have a wasted spark and/or dual tower coils DO NOT cut the loop. As you know, I cut mine too, like you, based on MSD's tech support. I wish I could get a good feeling that the solenoid was doing it's job. I suspect my numbers were good because my WUR just happened to be adjusted pretty close. I don't know, I'm still tuning. What's the best way to test the solenoid while the car is making power? Rig a light to it?
Old 07-25-2007 | 03:50 PM
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I might pull the chip and see if my numbers go lean...nothing under full boost or high RPMs, just to about 4,400 (the chip I've been using). If I go lean, this might give me the evidence that the solenoid is working.
Old 07-25-2007 | 04:03 PM
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John & sand_man,

I have a Leask's modified WUR and MSD solenoid as well. How did you guys find out that the loop had to be cut? Brian's instructions did not mention anything about that and I don't recall seeing an MSD manual.

Please advise as I'm seeing a similar problem on high RPMs...

Thanks,

GB
Old 07-25-2007 | 04:16 PM
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Originally Posted by AVID-928
John & sand_man,

I have a Leask's modified WUR and MSD solenoid as well. How did you guys find out that the loop had to be cut? Brian's instructions did not mention anything about that and I don't recall seeing an MSD manual.

Please advise as I'm seeing a similar problem on high RPMs...

Thanks,

GB
Careful, John and I have Elctromotive XDi ignition. So the unit supplied with Brian's kit didn't work properly with our ignition system - we had problems with the tach signal. So our controller is different than yours. If your ignition fits the criteria in Brian's manual (stock and/or MSD coil) your unit should arrive ready to go, no loops to cut.


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