Chevy280z

New engine build and low vacuum at idle 15Hg and running pretty rich. I'll list everything, 94 Z71 with 96 vortec longblock build, dual valve relief flat tops 9.78:1 with .060" quench Lunati
Advertised Duration (Int/Exh): 279/287
Duration @ .050 (Int/Exh): 213/219
Gross Valve Lift (Int/Exh): .447/.471
LSA/ICL: 112/108
Valve Lash (Int/Exh): Hyd/Hyd
RPM Range:1500-5500
performer air gap intake, tbi shop boared throttle body 46mm,transgo adapter plate on top of my old NOS brand spray bar plate ported to smooth out the transition to the carbed intake and yes the connectors are capped off, new AC DELCO 5.7 injectors along with all new ACDELCO sensors, new alternator, new 96 vortec fuel pump with 18 lb spring, new exhaust vortec stock manifolds to 2.5" to flowmaster Y new high flow cat, 3" to flowmaster single in dual 2.5" outs, timing set to 16 deg base. Using tunerpro RT to datalog. I had Harris burn my chip and recommended the cam and all. Any help is greatly appreciated, this is my daily driver and I love my old truck but after dropping all the $ I'm ready to have her running rite again!
Thanks in advance to anyone willing to help an old guy who hasn't tuned in over 15 years and never on a TBI.
Jimmie

Chevy280z

I will post the data log .xdl if someone can instruct me how, wont let me attach it?

Schurkey

1. 16 degrees of initial timing??? Is the "tune" compensating for that?

2. What is the cranking compression. (i.e., did you degree the cam?)

3. HOW do you know it's "rich"?

4. Got the correct spark plugs in those Vortec heads?

Chevy280z

1. Harris from Harris performance/tbichips said to set it at 10 base and after I told him it was only making 15 and running rich he said to turn it up to 18-20 for vacuum, it gained some power and 1hg but i turned it back to 16 when I heard pre ign ping, also while data logging it showed no knock retard from ecm?
2. I haven't bought comp gauge yet, going broke trying to get her running rite, got fuel pressure gauge on the way though. plan on comp gauge next, had a bosch but my nephews borrowed it and ya know how that go's..
3. I know its rich from the black smoke from exhaust, 10.5mpg, BLM and INT
4. yes sir, 44LTS

Fast355

iTrader: (2)

The problem is the Harris aka TBIChips chip. I have read a few of them and they were embarrassingly bad.

Chevy280z

I was afraid of that. I didn't have much time on the build and figured I would cut a corner and have him "custom make" a chip, and for $300.00 I figured he knew what he was doing. I still have my old chip burner so I ordered the Ostrich, a G1 and a chip, now I just have to get some good advise on getting the fuel and spark rite. I've been reading up on here and gearheads and It's obvious that I have a lot of learning to do. Any help or tips to make this easier on an old man are greatly appreciated.

Fast355

iTrader: (2)

Disable the EGR. Calculate and set your injector flow rate. Multiply your AE pulsewidth settings for bath MAP and TPS AE by about 1.5. Put a Vortec timing map into it. I have one that has worked well in several builds that I use as a starting point. The start datalogging and adjusting the fueling.

Chevy280z

That's a lot of good info but I may need it dumbed down a bit, makes sense on using the vortec spark tables, that didn't even cross my mind. May need some tutorial on how to do everything you said. I'll be reading up on it and try to figure it out. I only did tuning on 1 car years ago, it was an old 78 280z with lt1 intake that I modified for a dissy and old school heads, did 4 point cooling and remote t-stat. it was fun but I have forgotten what little I knew back then. but I will not let this truck beat me lol