nj1266

iTrader: (6)

IIRC most people that run EGT tend to target 800-850 or below. This is from reading about EGTs on Socalevo where most of the people tune on 91 octane gas.

As for the boost gauges, the most accurate are the MAP based ones. I have my XD-16 innovate gauge set-up to read boost from the 3 bar MAP sensor that I use to log boost. The guage has a circular LED display that you can custom color. I had mine set up to read green when in vaccum, one blue bar when the boost come one, red bars all the way to peak boost, and at peak boost (21.xx psi) one teal bar.

This has helped me a great deal in daily drivng. I can stay out of boost almost all the time. I also know when I hit peak boost everytime I go WOT.

housedj

iTrader: (2)

it is very well possible to blow a motor w/ good AFR's. the most common way people do it is by using stupidity. aalot of people think they can buy a boost controller, & flash & run 30PSI. it ain't gonna happen w/out some consequences. the stock turbo runs out of efficiency @ 25PSI. after that, it's just blowing hot air. also too much timing can be bad as well especially if u don't have a built head 2 go with it. on the '03, i am running between 20-23 degrees of advanced timing in my 3-5 gears spiking to 27PSI tapering to 23 by 7200rpm on stock cams & Sunoco GT Plus 104 octane unleaded with a flat AFR of 11.5:1 from 3300RPM all the way to about 6Krpm where it slightly dips into the 10.9:1 range by redline...

kjewer1

iTrader: (4)

The WBO2 I run has a free air calibration utility that I run every now and again.

I was going to say that the 25 psi figure in the post above is too high for aftermarket cams, but I see the stock cams mentioned at the end. Once boost starts to drop and airflow/time is maxed out, the turbo is maxed. The amount of boost this occurs at depends on the setup. With good intercooling this doesn't matter much at all, especially on race gas. The extreme example I like to give, just to illustrate the point, since it's not possible, is that with 100% IC efficiency, compressor efficiency doesn't really matter.

I can't recall if I already mentioned this in this thread, but I recall losing a particular motor at 10.3 to 1 with no knock at all. The cause was too much timing. I made an adjustment to my intake cam gear and forgot to reset base timing (2g with 1g CAS), so it was at 10 instead of 5. I knew I was pushing my luck with 23 degrees on the logger, but it was really 28. Number two spark plug came apart and ruined that cylinder. Lean AFR creates excessive heat, which can do some damage. But timing increases heat probably on an exponential curve is it is increased. It's directly linked to pressure, and pressure is heat. Timing is much more sensitive than AFR. It is also more likely to give you power gains that are worthwhile. Anything from 11:1 to 13:1 gives me the same trap speeds (more on the 13:1 in a bit). But a 1 or two degree change in timing, up to the low 20s, gives measureable power increases. It's very important to increase it 1 or 2 degrees at a time, and watch carefully for the point of deminishing return.

I recently started running BR8ES plugs. I've had so many mishaps with spark plugs coming apart I thought I would try something other than the BPR7ESs I've been running for 6 years. Last friday at the track, I dropped in the settings from my last dyno pull the day before, and for some reason still unknown to me AFR was 13.0 to 1 through all 4 gears. The entire run. And this wasn't a WBO2 error, DSMlink was commanding this same 13:1 ratio. This was with about 22 degrees of peak timing and as much boost/airflow as the turbo could make. I stongly feel that the only reason the motor surived was these plugs. I've lost many motors in similar circumstances. I immediately pulled the plugs after that run, and they looked as good as new. No signs of detonation either (no knock in the logs). I've had them in over a month now with no fouling or driveability problems. I'll never go back.

vboy425

iTrader: (19)

sure. i live in Los Angeles. Defilink BF gauges and Zeitronix setup show the same boost number about 21 psi spike taper down to 19psi. AFR 11.3-11.1, EGT peak at 830-840C. 91 octane

vboy425

iTrader: (19)

WTF is a WBO2 sensor ?? you mean Narrow band o2 sensor

nj1266

iTrader: (6)

No, I mean wideband O2 sensors like the Bosch or NTK sensors. These tend to lose accuracy over time and require free air calibration every now and then. Some wideband devices will tell you that your sensor is off and will tell you perform free air calibration like was mentioned by kjewer1

nj1266

iTrader: (6)

Did you log your boost numbers or were you just eyeballing the Zeitronix. In my case the Defi D was 1-1.5 psi off than the log showed.

vboy425

iTrader: (19)

GOTCHA

RECORDED BOOST AND EGT WITH THE DEFI LINK CONTROLL BOX AND LOG THE EGT, BOOST, AND AFR ON THE ZEITRONIX WITH LAPTOP