Hey guys, i need some help today quick! Im leaving for a road trip tomorrow morning, and im tring to figure out whats wrong with my truck! I just swapped in a 2004 6.0 into my 2002 Chevy z71 half ton. i installed a Comp cam 116-120 with 114* lift is around 530 i think. I also installed a set of 918 comp springs too. I installed a new yank tt3000 while i was at it. I have a transgo shift kit installed as well. and elelbrock headers.
Oh yeah, i got a whipple supercharger as well. When i did the swap, i COMPLETELY REMOVED the whipple eletronics. I installed 8.1 marine injectors flowing at 42# so i could remove the whipple aux injectors.
I have ls1 edit and i installed basicly a stock tune with torque management removed. as well as modified teh injector values to match the 42#ers.

My problems is the truck seems to run good. but it has no power. (I blew my 5.3 due to bad tuning, but my best run was a 14.4 in the 1.4 the g-tech was usualy fairly close.) my first run on the g-tech was a 16 flat. my best run yet is only a 15.5 I checked fuel pressure. and it stayed above 60psi all the way to 6300 rpms. the engine falls flat on itself around 4000 rpms. and the take off isnt impressive at all to boot! i can only get the yank to stall to 2500.

So im open to any and all suggestions, but i would love to get this thing figured out tonight for my road trip. Im starting to think its got to be something in the tuning. but i dont know what would make it run sooo underpowered.

I blew my 5.3 due to bad tuning, but my best run was a 14.4 in the 1.4 the g-tech was usualy fairly close.

 

What IFR did you use?? If you are still on a stock tune with the whipple/cam/injectors.. I would be willing to bet it is a fuel problem. I would get an afr meter or scan tool on it asap. In the mean time, I wouldn't be beating on it just by chance you are on the lean side.

 

i have a scan tool similiar to atap.. what exactly should i be lookin for?

And yes, its a stock tune

What is IFR?

 

I would pay to have it wideband tuned. Thats a pretty sweet setup, get a tuner on it to start.

 

Don't know if this will help or not but my first Nelson tune was accidently done for stock injectors. It did not run well and ran pig rich. Allen sent me a new tune for the big injectors the the Radix comes with and all is fine.
What he told me is the tune the Radix comes with the injectors are not open as long since there is a bigger orfice for the fuel to come out of. If the injector duration time is open like stock LB injectors the thing will dump a ton of fuel because of the time that they stay open.

Could this be the problem that you are having since you now have the 42LB injectors?

 

if you can only get the Yank TT3000 to stall to 2500 you are having torque production issues......to me it seems that you are running PIG RICH, part of that may be due to the stock IFR table (injector flow rate)....the computer still thinks it is driving 26.4lb/hr injectors, with 42lb/hr injectors installed you are getting almost twice as much fuel as necessary and there's no way the computer can compensate for it because it doesn't even know there is anything wrong !!!

pull your dipstick and smell the oil....I garantee it'll smell like gasoline, also at idle go sniff your tailpipe.....I bet it smells like gas station behind your truck when it's running !!

you really need to get that thing tuned before you hurt the motor....and you CAN hurt a motor by running too rich, you can wash the oil off the cylinder walls and cause serious internal damage by running too rich

PLEASE for you own sake DON'T take that thing on a road-trip without getting it tuned first

 

The IFR (Injector Fuel Rate) is the number telling the computer what size injectors you have. What table did you change values in alread? From everything I have read, you should have around 5.12 across the board for the 42#. This is in the IFR table.

 

Part of the problem was he was only getting ~2* timing up top with 2 psi. He's now seeing 3 and 4 psi just before he shifts. It has a bit more timing and leaned out a hair more. I think he said he picked up a whole second off the initial run.

THe IFR is at 5.20 right now and still getting -4 to -7 ltrims. On a WOT run, the o2's look good though.

 

flyer is correct, with 1 new tune, i dropped a second off that time. i still think alot is to be gained though. im only running a 14.4 with my setup. i know its got more in it.

 

I thought I heard the 02's don't actually function at WOT?