greentahoe

iTrader: (2)

Im curious to see what you guys are seeing. Also if possible list your IAT's, outside temps, etc.
It looks like Im seeing about 57-58lbs/min at 5950 but it starts decreasing as I near the 6000 shift point. At 5988 Im only seeing 52.75lb/min. Does this mean Im outside the blowers capablities at this point?

v8

iTrader: (10)

not sure on the outside blower capablities, but N/A im seeing 42 to 44 on mine all the way to 6600 in 1st and 6400 in 2nd.

CHarris

iTrader: (5)

1st gear Airflow: 460 g/s and 60.68 lbs/min @ 5970 RPM

2nd gear Airflow: 464 g/s and 61.26 lbs/min @ 5907 RPM

Outside air temp 50-55 degrees. IATs start at 105-110 and go to 160 at the top of 2nd gear.

I expect airflow will increase a little yet again after I buy and install my new injectors.

greentahoe

iTrader: (2)

Im curious if I wouldve seen more if temps were a little better. It was about 78* outside. What do you think about the drop in airflow between 5950 and 6000??
How much timing are you seeing?
How much rwhp are you seeing? Ive read there is a pretty close correlation to g/s and rwhp. Do you know the formula to convert it?

CHarris

iTrader: (5)

I get a drop in airflow at a higher rpm, too. I can see from my datalogger that it is due to the shift initiating. I'd expect yours is doing the same.

I've got 12 degrees from 1200-2200
13 degrees at 2400
14 degrees at 2800
15 degrees from 3200-4400
16 degrees from 4800 up

I did just change to TR6 plugs today. My stock plugs showed enough color change on the insulator and the ground strap that I'm sure it was the right time to change. Maybe I'll get to add a point more across the band. Sure would be nice. As it was, last time I logged I'd see .1 knock retard at about 2800 rpm. No other KR anywhere else. When I down in pulley size I had to scale back my aggressive timing.

No idea on the RWHP. I've got full time 4WD and the transfer case and system is not the same as the Silverado SS. My wheels and tires scale at 99 lbs each and the race weight of the truck is 6800 lbs. I doubt RWHP on my truck would be comperable to other trucks even if I knew the figure. My track times are all I can judge by. I convert airflow lbs/h to g/s by changing the measuring settng from imperial to metric on HP Tuner.

BigTex

iTrader: (16)

I wish I could rely on the MAF for the complete run. I hit the MAF peak in the low 5000 rpms, which is 454 g/s. I do log the raw MAF Hz, which continues to rise and peaks between 5800-6200 for me.

I went to the track and hit the MAF limit doing my 4 wheel burnout in staging.

parish8

iTrader: (6)

i was maxing mine out at 60lb/min at something like 3500rpm, highest freq i remember seeing was something like 13,500.

greentahoe

iTrader: (2)

If Im using a wideband for AFR, would maxing it lead to any other difficulties in getting it tuned correctly?
What exactly happens at that point.
Im using a 3.12 pulley right now and shifting at 6000, I may through my 2.87 on and play with that for a while until my T trim gets here. Then Im going for the fastest Tahoe on the board.

parish8

iTrader: (6)

maxing out the maf leaves you with only the PE/rpm table to tune with. you can tune this way and get your fueling to do what you want but the problems start when the weather changes.

if your tuning based just on rpm things will change with weather.

if your just bumping the limit then it isn't much of a problem but if you are flatlineing that sensor at something like under 5000rpm then tuning gets dificult.

parish8

iTrader: (6)

btw. for rough tuning when the maf is maxing out i was told to add .03 to the PE/rpm table for each cell starting at the point where the maf maxes.

for example if the maf maxes at 4500 and you have your fueling prety close up to that point at 4800 you should add .03 to whatever your 4400 cell is, then add .03 to your 4800 cell to get the 5200cell. do that over and over to the end of the chart. i used these numbers and it worked prety well but like i said above things change with weather.