I'm in the process of tuning my turboed zc with chrome and for some reason at 5psi it wants to go instantly lean. I can partial throttle it to red line and have plenty of fuel as long as I keep it lower that 5 lbs.
Info:cut is set at 7800 rpm (built head) and launch control at 4200. I'm running rc 750s and a walbo 255. Gm 3 bar that worked in last setup.
I'm gonna try a different map sensor but if that doesn't work, other ideas would be appreciated. Also, boost cut is at 22lbs.

 

injector size?
plug gap?
what does your table timing look like?
how does the fuel curve look?

 

What impedance injectors ?
Are you running a resistor box ?

 

750cc injectors with aresistor box. The whole setup was swaped from my ef hatch wich ran great. All I changed was converted to chrome from zdyne, built the head, different turbo, intake manifold and throttle body, and different resistor box. So it has to have somthing to do with chrome, resistor box, wiring or maybe a bad sensor. As far as the map, I used the core performance bin from xenocron, and made a few small adjustments to the low cam fuel table.

btw, if the plug gap was off, it would cause lack of spark wich would show rich on the wideband...right?

 

bump

 

Check your plug gap & get back to us.

 

email the .bin out of your ecu so I can check it out for you.

 

as far as the bin goes, I just started with the core performance bin off xenocron. and added fuel. up till 5 lbs it is very smooth. I've gone as far as bumping up to 100% duty cycle across the board in boost and still acts like it hitting fuel cut.

http://www.xenocron.com/bins/i...=Corr Performance TUNE d16y7.bi&directory=Crome/D-Series&

 

Did you ever check your plug gap ?

 

new ngks with stock gap. Im gonna try gapping them down today.

 

btw I checked the fuel pressure and its at 78psi. Regulator is good and return line is clear. Could this cause a lean out? Any ideas on what causes high fp other that the regulator.

 

the duty cycle information in crome is garbage. Ignore it. Truth is that crome doesn't give you any way of knowing what the actual duty cycle is.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dseriesdrag &raquo;</TD></TR><TR><TD CLASS="quote">new ngks with stock gap. Im gonna try gapping them down today. </TD></TR></TABLE>

There is part of your problem.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dseriesdrag &raquo;</TD></TR><TR><TD CLASS="quote">btw I checked the fuel pressure and its at 78psi. Regulator is good and return line is clear. Could this cause a lean out? Any ideas on what causes high fp other that the regulator.</TD></TR></TABLE>

Here is another part of your problem, try a new gauge.

 

word conan

go to .030 gap

 

I gapped them down to 27 wich is what I had on my last setup. No luck.

Also, the guage is not the problem. I've tried two guages and a $400 matco fp tester. All are reading between 75 and 78psi at the filter banjo bolt.

 

can you email me your bin file?

blakesvtec (at) yahoo.com

 

Wait ... What's your base fuel pressure?

 

how lean are we talking about here?

your fp is too high. it should be from 35-45 only.
injectors stack up at very high pressure.

 

problem solved. Washers from fuel line to fuel rail were switched. The copper washer was between the line and the bypass valve. Therefore, it was blocking fuel from the fuel rail and raising fuel pressure in front of the fuel rail. I'ts always somthing stupid, but I'm glad it was somthing cheap!