C5 427 Twin Turbo Startup Tune Help - Files included

[Turbo-Geist]

I have a new 427 twin turbo engine in a 99 C5 Corvette. It was previously a stock LS1 twin turbo with a cam. Previous injectors were ID 1000s and the new injectors are ID1300s.

I went to Injector Dynamics website and downloaded the GM characterization tables for the ID1300s and plugged them into the original twin turbo LS1 tune.

Here is the 427 TT tune:
427 current tune idle ve changes.hpt

Here is the config file:
Ben Imp AFR LM2-SD-2.5 BAR TI.cfg

Here is the log file from an attempt to start but it is too rich even after taking 20% out of the idle areas of the VE table:
1st try ID1300 data.hpl

On the above tune, it will fire and then die immediately and the wideband shows 9.5:1 AFR. With the old LS1 twin turbo tune, it will fire and remain running if you give it some throttle and hold rpms steady.

Here is the LS1 TT tune:
LS1 TT current tune.hpt

I'm using the same config file:
Ben Imp AFR LM2-SD-2.5 BAR TI.cfg

Here is a log of the new 427 TT with ID1300 injectors but ID1000 injector data. This is the only way I can currently get it to run and idle:
2nd try ID1000 data.hpl

Any help is greatly appreciated.

[mecanicman]

Fix your map sensor, its not reading correctly. Stays the same no matter what is going on. Change p0103 to 0-mil on first error. Set Engine-Airflow-Dynamic-High RPM Disable to 12800.

[Turbo-Geist]

Thanks. It's amazing the simple little things that can trip you up. I wasn't even paying attention to the MAP. This is a gen3 to gen4 swap and I had the 2 connectors behind the intake plugged into the wrong connector on the swap harness. Now the battery is dead so I've got it charging and will test again after work. I'll report back. Hopefully everything works out. It was sounding fairly ragged before.

[Turbo-Geist]

I got a chance to fire it and scan last night. The MAP sensor is now working.

Here is the tune file:
427 current tune.hpt

Here is the 2nd scan after the engine died, ECT is 163F:
9-22 2nd start.hpl

I'm using the same config file from the 1st post.

Here are my notes from this scan session:
"Frame 3413 to 3489, TPS is 13%, rpm is 1080 to1300.

At frame 3490, there is a slight tick down in TPS %, timing drops and rpm starts to trend downward. Injector duty cycle goes from 2% to 1%. The engine then tries to catch itself and rpm begins to swing. Slight increase of TPS to 15% corrects the condition and then TPS can be held at 13% again.

You can see stuff like this happening from the 6 minute mark till about the 7 minute mark. I'm holding the throttle at a steady value and trying to see if I can walk the throttle down incrementally and get the engine to idle on its own at the set idle speed. Right now, it won't."

Basically trying to get it to idle on its own right now. Any suggestions?

[Turbo-Geist]

I have ETC scalar set to 0.0192 for the LS2 throttle body and I pulled the IAC Steps vs. Effective area from a 4.8L truck based on something I read here on the forum hpt. Not sure if I should go back to stock values in this area.

If any additional details are needed on the engine specifics, I can post them up.

Change p0103 to 0-mil on first error. Set Engine-Airflow-Dynamic-High RPM Disable to 12800.

I'm going to change these this afternoon and reflash.