Date:         Sat, 19 May 2001 22:00:53 EDT
Reply-To:     Wolfvan88@aol.com
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Robert Lilley <Wolfvan88@aol.com>
Subject:      Re: Still running rich
Comments: To: Brewhogger@aol.com
Content-Type:  multipart/alternative;

<<<Measured fuel pressure:  36 psi at idle with vacuum connected.  42 psi (at 
any engine speed) with vacuum line disconnected.  If increase engine speed 
(with vac. connected), fuel pressure decreases (yes, DECREASES) to about 32 
psi.>>>

Stock pressure regulators pressure is set 29 with vacuum 36 without vacuum.

When the engine increases RPMS, the vacuum increases and lowers the pressure. 
 On my dual diaphragm adjustable fuel pressure regulator (I increased the 
stock cam duration by about 8 degrees and was told that this would lower the 
vacuum.  I think that with all the other changes to my engine, it was not 
affected), it would drop down to 22 psi, I felt that this is too low.  I 
tried different ways to restrict/reduce the vacuum, but none seemed to work, 
so I cut some holes in one of the diaphragms to reduce the pressure drop.  
That worked and the power increased at upper rpms (4000+).

You can get a stock regulator or a single diaphragm one from CB Performance 
and that set it to your engine.
Your regulator is damaged and giving you too high a fuel pressure even with 
the hose off.


<<<An observation:  I noticed that the position of the AFM wiper is about 20 
or 25% "open" with the engine idling.  This seemed surprisingly high to me, 
but I have no reference.  Could be normal.>>>

Mine does the same during my testing.  At 4500 rpms the AFM was not at full 
swing either.


Robert

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