95maroboi

Im hoping someone on here can help me with my issue. I took my car to get dyno tuned and it's not making close to the power that it should be. The air fuel ratios are good but the tuner said sometimes the car would go more lean on the next dyno run without changing anything. I started losing power past 6 psi. The Power would drop then rise then drop again. Here's what the dyno chart looks like the tuner said the timing and air fuel ratio were really good but he can feel something holding the car back and thought it could be a burnt wire or bad spark plugs. I pulled all the spark plugs and 3 of them looked extremely lean . . Sense the car sat for 4 years were thinking it could be clogged injectors so I have them being checked as I type this . Any help would be appreciated . The motor is a 385 cu in. Lt1 with 195 afr eliminator heads hand ported, custom le blower cam and a vortech v7 ys supercharger so it should be around 550rwhp with the boost I'm running. The ignition system is a msd opti,msd coil,msd 6btm ignition . Fuel system is 60lb injectors , racetronix in tank pump with hot wire kit and an extra external pump so I don't think the fuel system is the problem . Had this same fuel set up on my last 355 combo witch is making more power then this set up so there's definitely something wrong here

rwb

You say that it goes lean, then it is your fuel system. Check your regulator to see if it holds constant pressure, also check your vacuum lines for a leak on the fuel regulator. Look for all the little things first.

ponyackn

Bump for ya man. I hope you can get things sorted out. Is there any belt slip? What amount of boost are you looking for?
It seems like any of the few who've run the YSi on our LT1s encountered belt slip and needed additional bracing fabbed up to keep things straight. I'm curious just in case I ever decide to bump up to the V7 as well. Sounds like your setup should make killer numbers when dialed in.

95maroboi

The fuel pressure is good and didn't drop. I pulled my fuel injectors off to get them tested and it turns out that half of them went bad from sitting. 2 injectors were down 40 percent flow,2 were down 20 percent flow and 1 was down 4 percent. I'm hoping this takes care of my problem.im re installing everything today to find out

95maroboi

I have my big pulley on so I'm only making 8 psi up top. There's no belt slip at this amount of boost for me but I will be switching the pulley for 15psi once I get this situation figured out. I'm running a cog set up so I shouldn't have a problem with the belt slipping . I found out my fuel injectors went bad from sitting so I'm installing new ones today to see if that fixes the problem . I have a air/fuel gauge on my car so if I go super lean up top that should tell me if that was the problem or not.

95maroboi

So I changed the fuel injectors ,spark plugs and made sure there were no wires against the headers. The wires are new also. I'm having a gestation problem from a slow roll/stop soon as I push the gas it hesitates to about 2k Rpm then pulls just fine. I'm having a hesitation problem at WOT also where it was hesitate once or twice around 3.5k Rpms then pulls hard after that. Any ideas on what's causing the hesitation? The maf is new I'm using a ls7 maf. The msd opti,msd coil and msd ignition box were used when I bought them from a member on here. No codes are being thrown either