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Hey all- this is my first post on here. Just for comparison, I would like to see waht your target air fuel ratios are. With our elevation and 91 crap gas, it seems I cannot go any leaner than 10.8-1 without getting knock. My timing is on the conservative side and I hit a peak boost of 17.5 on my p&p td04. I appreciate input - thanks

correct me if im wrong, but you need a wideband to correctly get your AFR

Need lots more information here.
EM, supporting mods, targets, how are you measuring... etc... 17.5 on the TD-04 is pretty close to turning it into a flame thrower, getting close to beyond efficiency range there....

Sorry guys- I forgot that I had not yet filled out my profile. I am using a wideband to monitor. My car is an 02 wrx, open source tuned. basic stage 2 mods 3 inch tbe, up pipe, etc.... I am just looking to get a basic idea of what other tunes are running as far as AFR's

I realize 17.5 is pushing the turbo, It will briefly spike to 17.5 in fourth & fifth gear. I have taken the time to log boost along with maf G/S to find the point where increasing boost yields no gain. Anything above 18 and I lose G/S.

Um your air to fuel ratios go like so.... 14.7:1 is perfect but this is the real world and it never happens. anything less is rich, and above is lean

Im talking about WOT- thanks

From a conversation with a couple tuners, they say 11.0:1 is pretty much as low as you can go for reliable power with the TD-04 on a "stage 2" 3" TBE setup. All setups will be slightly different (due to manuf. tolerances), so check your logs. Tweaking slightly from standard OTS maps will help you get the best results.
Out of curiosity, are you using mechanical or programming to get to 17.5? I find the WG starts blowing open after 16.

I am using a hallman pro MBC for boost control.

Do you have an EGT gauge?

What is your timing at?

Bones: 14.7 is stoich. You really only want to run that when cruising in closed loop. In open loop, not only is that considered very lean (since stoich is very prone to pre-det, turbo charged or not), but you will want to run richer than that for better flame propagation (which equals more torque).

Max power rich for gas is: 12.5
Max power lean for gas is: 13.2

On turbocharged cars it get's a little trickier since you want to avoid pre-det/knock as much as possible. Don't quote me on this, since every cars setup is different. But, on a FMIC map you can get closer to 12:1 and in the low 12:1 ranges, and a TMIC would be more in the range of high 10.5:1 to low/mid 11:1. Of course it can be beneficial to run ~ 13:1 in certain areas to benefit spoolup. I am giving a hugely VAGUE generalization here.

Also, I believe with the atmospheric elevation pressure difference at 4,500ft.... 17.5 psi of boost is equivelant to ~19 psi at sea level. Which is out of the efficiency range of the TD04. You may be squeezing a few more G/S out of it.... BUT I think that you may even get more power out of a lower boost, higher timing and slightly leaner fuel map. Obviously these are stabs in the dark since I am not familiar with your map and cars setup. Some experimentation and road dyno software would be very beneficial in this situation if you haven't already done so.

I am also still in the learning process of tuning, so don't take what I say as pure fact.

For my current map, with a TD-04, TBE, STi TMIC, I'm running the following AFRs (under WOT):

13.5:1 @ 2600, tapering fast to 12:1 @ 3500, then a slow taper to 11.5:1 @ 4500, then down to about 11.2:1 @ 6500.

This gets me 225 WHP, and 245 WTQ on Cobbs Mustang Dyno, 92* at 5200 ft.

Thats what I was llooking for, thanks. whats your timing like? (@ pk trq, redline) and how much boost? if you don't mind.

my timing is pretty conservative compared to other maps I have seen. at peak torque 10-11 degrees, up to about 24 @ redline. My turbo is ported and polished also, so it is a tad more efficient. I have tried running less boost but I still get random knock with lower boost.

I was running a peak of 13.5psi @ 3250 tapering to 12.5 @ 6500. Not sure on the timing.... Sorry.

that 13.5 is actual boost you are seeing after going through the elevation table correct?

Quick question, did you leave the atmospheric compensation table as is, or did you clear it and just take elevation into consideration in your target boost maps?