will you guys take a look at my tune? i'm only cuttin like 2.4x 60'. I'm runnin 275/60 15 mt et street radials now, i cut the same 60's with 285/60 16 street tires and the same thing with my 20's. can you look at my tune and see if i've looked over anything...i have a LITTLE cam 212/218 low lift. i don't have my converter in yet but i still feel i should be cutting better 60's.

 

I did not see anything but what is the big hole/dip in your Spark Timing table? Did you log any of the runs? Did you brake stall at the line?

 

i just stall to around 900rpms that seems to be where it does the best. the dip is just where i haven't raised the timing from stock...

 

Well, at first glance, what I see is this.

I'd suggest using PE mode for your high load fueling as opposed to the Commanded Fuel in Open Loop table. Reasoning: Your fueling needs are much different at full load at 1600rpms than they are at 5600rpms. Also, you're running a lot leaner than you need to be. 13.1 may be what some say makes best power... It's an arbitrary choice. Take any AFR from 11.5 - 13:1 and you'll have a difference of 2-3hp, max. I've found best power on the dyno to be a bit richer than that. Safen your tune up and richen that a bit.

Spark table: Just like your fueling needs are different at 1600rpms than at 5600rpms, so are your spark requirements. At lower RPMs, there is a lot more time between combustion events, causing you to need much less timing to achieve the peak cylinder pressure effectively. Running 27-28* down low is simply too much.

Can't guarantee that this will help your 60', but they are what jumped out at me.

Justin

 

Well I can't see the tune, but there is one thing that is consistent with your set up that jumps out at me....

It's the driver... do you think that could be the problem???

 

his A/F is mid to upper 12's across the board through the rpm range..i dont know why i put 13 in there and not change the ve table..

 

Try moving the rpm in D2001 to a number higher than your max stall rpm. Or just zero torque reduction in abuse mode.

 

If you've figured out more stuff and want more practice let me know. I don't mind getting mine tuned some more.

 

I don't really understand why you are running open loop speed-density on your setup, but it comes down to fuel and spark. A little richer mixture down low in the rpms to about peak torque will help make more torque, and then leaning it out a little up top will help make a little more hp. 12.5 then leaning to 12.8~13.0 is what I usually target. Timing is something that more does not always mean more power. I have personally seen on a 226 cammed Silverado 5.3 (Tan327), that from 26* to 30* made no power difference at all. It is all about the setup, the more efficient the setup the less timing it may want, just something you'll have to find out. 28* is not the magic number for all combos. I have some F-body cars (full bolt-on) that run 93 octane, that I only run 24*-25* on and on a street tune, one friend (John02Hawk on LS1tech), dynoed his car and put down 344/356 I believe on that tune.

That being said, if fuel and spark are close, it may just be time for a converter.