high map on hwy

[PJG1173]

Ok, so just when I thought things were going good I took my truck out on the HWY 17 bypass (all 3 miles of it we have) where I could safely get up to 65 - 75 without hitting a stoplight. there are several bridges and overpasses so I though that would be a good place to get some logs. needless to say I never got that fast. at about 60ish MPH in 4th in TC lockup 1900 RPM map was at 95+ kpa. I had to keep the trottle at 50% to maintain 65 MPH any more and I would have been in PE. what gives? do I need more/less timing? attached is a copy of my logfile and the adx file i'm using. If someone could look at it and point me in a direction that would be helpful.

[EagleMark]

Something is wrong that's for sure, I'll try to find some time to look at your log today but tell us which vehicle, and specs.

[PJG1173]

this is on my 93 chevy s10 ex cab
4.56 gears
36x12.5x15 TSL's
01 4.3 block bored .030
9.8:1 compression
edelbrock 2114 dual plane vortec intake
transdapt tbi adapter
61lb injectors @ 13psi
adjustable FP regulator
TBI with ultimate tbi mods
ported and polished vortec heads
back cut valves
comp cams 266hr
1.52 roller tip rockers
hedman long tube headers
kwik-cat racing cat
cold air intake
built 4l60e
2075 stall converter
Crane HI6 CDI ignition

[EagleMark]

That thing should run better than that!

Your open loop the entire time so I'm guessing your tuning VE by the wide band. WB AFR are in the ball park. Spark advance is a little low, especially at idle around 14 degrees and 650 RPM with a slight fluctuation of MAP. I would raise the RPM up to 750 or so, set base timing at 10 degrees? Also set base timing in chip from 0 to 10 and see if that fluctuation goes away. If not look for a vacuum leak.

Are you using the Narrow Band simulator? Your O2 readings and cross counts are weird?

I can see where your trying to cruise at 60ish MPH and MAP is 95ish with steady state TPS. Narrow band reading is way lean. WB is close. One thing that stands out is WB AFR is fluctuating, this may be a cylinder misfire or miss, I would check actual timing with a light on balancer and see if data log spark is showing same as timing light. Also pull plugs and read them to see if one is off. If one has a miss or one cylinder is picking up a vacuum leak it will throw everything out of wack...

[PJG1173]

Base timing is set to 6* and properly reflected in the bin and adx. Idle timing is 20* verified with a dial back timing light. I've looked for a vac leak but might be something that only leaks while under a load. The NB is the factory one when i was simulating the reading was more stable. at anything below 50 mph cruising this is great. WOT is on point pe 12.8 ish through the rpm's. just seems like this thing can't hack rolling down the hwy at 60 - 65. I wish I would have better datalogged this thing when it was stock.

[EagleMark]

Timing I saw in log at idle was only 14? So we're losing 6 degrees somewhere? Since you have a dial back timing light see where timing is at higher rpm, in the data log there was a lot of 24ish degrees around 2400 RPM. The fluctuating WB AFR reading still seems to indicate a miss fire, at this point reading plugs would still be a good idea

I'm not familiar with the Crane HI6 CDI ignition at all?

Vortec heads have a very different spark plug?

Vacuum leaks are much more prevalent at idle when vacuum is higher then say 95 MAP when there is no vacuum... I have found vacuum leaks with short bursts of starting fluid when brake clean and carb clean have failed. Please be very careful using SHORT bursts of starting fluid as it is very flammable. Another approach is a propane soldering torch unlit wide open pointed at anywhere they could be vacuum and listen for rise in idle.

But I don't think that is your issue at 60 MPH at 95 MAP 40%+ TPS is just dead on power? Do you have a thick vacuum hose that won't collapse hooked to MAP from center vacuum port on rear of TBI between fuel lines? I did see AFR go to 10 when decelerating at one point then climbed back up to 17.9 before it became stable again?

Just going over some basics here, I don't know if they will help maybe someone else can see something I missed?