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quattrorunner quattrorunner is offline
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Join Date: May 2006
Location: Las vegas
Posts: 5,984
Originally Posted by DSPTurtle View Post
Set your fancy AFR numbers aside for a short time... hook up your "chinese" fuel gauges again and get yourself four measurements to start with. System pressure, cold pressure, warm pressure and full throttle enrichment. You need these four numbers to make sure that you are at least in a good gross starting point. After that, you can dink around with the CO adjuster and tweak your pressures slightly for optimum AFR. But at this point it sounds like you are not confident in your WUR so your AFRs will never be repeatable.
There are all kinds of write ups here but you asked for tricks...
1. hook up battery charger
1a. hook up pressure gauges
2. unplug wur heater connector
3. write down system pressure and then cold pressure numbers, compare to spec
4. plug in heater connector, let pumps run for about 5 minutes, write down warm pressure
5. put 7 or 8 psi into the WUR boost nipple and you should see the fuel pressure drop (the trick here is to not over pressure the WUR and blow up the diaphragm... use a brake bleeder pump to add pressure very slowly), write down the full throttle enrichment reading
Once you have those numbers you will know how to attack the adj WUR. My guess, based on your original post, is that your "full throttle enrichment" measurement will be much less than the 2.9bar that is in the spec. That is an easy adjustment depending on which version of the BL you have.
Thanks, I'll try this again today, these are similar instructions if not exactly the same as I have, which are understandable.
But, as another question about that mityvac, it's a vacuum pump not a pressure pump, how do I apply pressure from a vacuum pump? I got one (a mityvac as prescribed) and I can't logically figure out how vacuum can translate into pressure? Am I stupid?
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Old 03-08-2014, 07:52 AM
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