e38 ls7 - full top end - 72lb injectors - barely runs - tune & log file inc.
Hey Guys,
So i am still learning all the ins and outs of tuning. I see 50/50 responses on MAF and Speed Density, and now i have a HUGE issue with getting the car to idle with 72lb injectors and massive cam. It is similiar to the texas speed 4.2 LS7 cam.
It is a greg good custom grind HPC "hulk cam" which they do not give specs for.. so based on the 4.2. the specs are the following:
3000-7000 RPM Power Band
Cam Specs: 248/260, .657"/.655", 111 LSA, 108 ICL
I tried the big mike idle procedure for idling -- would not work for me. I partially tuned the MAF with the 42lb injectors and car would surge bad -- and NOW the car bucks like a raging friggin' bronco.
i have also installed 72lb injectors. I didnt go with 60 because i plan on trying to squeeze more power at some point (procharger or 150 shot).
My injector flow maxes out at 63.5.. So i followed the advice of the tuning school and flat lined the table at 63.5 and added the remainder to the voltage multiplier table.. I know some guys on here say this is the incorrect way to do so .. so what is the correct way when the table pegs out so low?
The car is pig rich sometimes, then so damn lean at idle that the AFR pegs out at 2 lambda. I reduced the VVE 10% at rpm from 0 - 1200 and added 10% from 4000 and on and the car is running horrible.
I am seriously lost and no matter what path i take, i am not making any progress. I am really thinking of ditching the MAF ( i originally had the 2 bar MAP OS for SD and went back to the base OS -- cuz the tuner i was going to use said that is what he prefers, but the guy is very shady ).
Should i go with SD, is there a procedure or good way of doing this to get the car drivable? Help would be greatly appreciated.
Car specs:
07 z06
Frankenstein LS7 ported heads
Mamo ported MSD intake
katech 103 TB
Vararam SC1R
1 7/8 headers
high flow cats 3 in to stock z06 mufflers (upgrading soon)
johnson 2110r lifters
greg good cam
c5r timing chain
ATI damper
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