running lean after istalling MAP bleed???

[k-briggs]

i just installed a g-valve MAP bleed. followed the directions right from gus's site. but now i seem to be running very lean in WOT. could this be related?

thanks
kyle

[xrattiracer]

well when you fool the map sensor by making it think it is seeing less boost than what is really there, what do you expect?

[k-briggs]

but tis leaning out at all boost levels. it never went higher than 15psi. its got enough fuel for that.

[gasketmaster]

Are you seeing the proper map voltage at WOT?

[anonymous_user]

A MAP bleed will lean out the whole curve. You are bleeding off some of the manifold pressure before it gets to the MAP, so if you are at 5 psi manifold pressure, you might only see 3-4 psi at the MAP. You will need to raise your fuel pressure to compensate.

Now, if you are using a pressure relief valve on the MAP signal - aka a grainger valve type MAP clamp - then it should only lean out when the valve opens. You will need to control fuel above the setting, but below it should be fine.

When you say a MAP bleed, do you really mean a bleed or a g-valve type?

[k-briggs]

this is what i have.

[RPMurph]

what happens if you tighten it?

[detobias]

the ball/check G-valves dont necessarily seal 100% when they are closed so you may have a slight 'bleed' at pressures less than you expect

a slight leakage may not be significant when operating on a wastegate circuit, but perhaps significant on a MAP vacuum circuit

I'm running a 4.3v zener diode myself - essentially functions the same way as your Gvalve but does it electrically instead of pneumatically; also simpler install, cleaner (hidden), less chance for errors & problems (e.g. dirty & sticking or leaking Gvalve)