running rich or not enough fuel?
 

When driving around town at lower rpms the car would studder/misfire and spit black smoke from the exhaust but once in the 3000rpm range it goes away. The car at idle is fine though. I replaced the spark plugs with new NGK BPR7ES(gapped at .030) and checked the plug wires(NGK) and its fine.
Also highway driving around 60mph my boost gauge would read 5psi and car would studder slightly, around 70mph the car would studder a tad bit more and the boost gauge would read 10psi backfire and in doing so spit some black smoke.

And ideas as to what would cause this? My brother-in-law, who's a technician, said the black smoke is because I'm running WAY to rich and should find another way to get more air or that I'm maxing out my injectors and need bigger ones. Does that sound reasonable?

My current mods: '99 spyder gs-t
-evo3 big16g turbo
-450cc injectors
-walbro 190lph
-AFPR
-7" ETS short-route FMIC system w/ GM MAF-T setup(recently just installed)
-SSQV BOV
-3in turbo back exhaust
-apexi safc(settings zeroed out)
-dejon tool intake
-boost and air/fuel gauge

I know I need bigger injectors and will be purchasing some PTE 680cc on my next paycheck.

Re: running rich or not enough fuel?
 

You definitely need bigger injectors, but yeah, black smoke is running rich. Pull some fuel out of your lower rpm settings on the SAFC, and gap your plugs at .027". You obviously meant .030 instead of .3, but that's still a bit of a gap for any boost.

Re: running rich or not enough fuel?
 

Yeah sorry I did mean .030. I'll fix that in the original post. Anyways, roughly how much fuel would I need to pull on the SAFC and in doing so should I get a logger to monitor the car?

Re: running rich or not enough fuel?
 

680s might be a little big for your current setup

Re: running rich or not enough fuel?
 

Yes possibly but I would rather just buy it once and not worry. But this isn't about what injector size I'm getting or should get. I have an older thread debating that and thats how I came to wanting the 680cc and I'll leave it at that.

Re: running rich or not enough fuel?
 

I hear ya on that.

Re: running rich or not enough fuel?
 

Just pull out a little at a time until it doesn't misfire.

Re: running rich or not enough fuel?
 

680's will be just fine with a MAF-T/SAFC combo. As for your issues, I'd suggest getting some dyno tuning time on the car

Re: running rich or not enough fuel?
 

Okay I'll give it a shot.

Yes I plan to get some dyno tuning done but I must first get it running decent :P.