454 TBI for '98 350 Vortec

[dave w]

Dave: Need help with TunerPro RT. Can the ADX file be expanded to include such parameters as Open/Closed Loop, MAP etc.? Need to diagnose why after warming up the 350 Vortec goes from rich to lean and then dies. Fuel pressure remains stable during this event. Your recommendations on these aspects would be greatly appreciated.

Please refresh my memory, which ECM / PCM are you using?

dave w

[rsicard]

Please refresh my memory, which ECM / PCM are you using?

dave w

Dave: The ECM is a 16197427 with BJYB binary loaded into the Flash chip. I suspect that there may be a vacuum leak between the throttle body and 4 barrel adapter or between the 4 barrel adapter and the 4 barrel manifold. The adapter plate is steel and 1/4" thick so the holes are threaded for the bolts with the 454 throttle body with supposed 65 Lb/Hr cop car injectors. They came unmarked to I really don't know the actual flow from them. I did not drill into the 4 barrel manifold for the TBI bolts. At this configuration, the open loop runs at 10 - 11 AFR as read on a Innovate Motorsports LM-1 and wide band sensor. Apparently when up to temp and going into closed loop, after a short amount of time, the AFR goes from 10 or 11 to greater than 15,, 16, 17 and then the engine dies. Also the idle is very high approx 1900 RPM. There is NO idle adjustment screw on the 454 throttle body. This has repeated 3 times already.

Next step is to drill clearance holes in the 4 barrel manifold for the throttle body bolts which at present have many washers that do not allow projection into the 4 barrel gasket between the manifold and the adapter. Then apply sealer to the 4 barrel gasket and to the throttle body gasket to make certain there are NO vacuum leaks.

Then run the engine again with the same binary. Also have a factory binary for the Vortec with TBI for export trucks. May try the latter binary later.

[Fast355]

Dave: The ECM is a 16197427 with BJYB binary loaded into the Flash chip. I suspect that there may be a vacuum leak between the throttle body and 4 barrel adapter or between the 4 barrel adapter and the 4 barrel manifold. The adapter plate is steel and 1/4" thick so the holes are threaded for the bolts with the 454 throttle body with supposed 65 Lb/Hr cop car injectors. They came unmarked to I really don't know the actual flow from them. I did not drill into the 4 barrel manifold for the TBI bolts. At this configuration, the open loop runs at 10 - 11 AFR as read on a Innovate Motorsports LM-1 and wide band sensor. Apparently when up to temp and going into closed loop, after a short amount of time, the AFR goes from 10 or 11 to greater than 15,, 16, 17 and then the engine dies. Also the idle is very high approx 1900 RPM. There is NO idle adjustment screw on the 454 throttle body. This has repeated 3 times already.

Next step is to drill clearance holes in the 4 barrel manifold for the throttle body bolts which at present have many washers that do not allow projection into the 4 barrel gasket between the manifold and the adapter. Then apply sealer to the 4 barrel gasket and to the throttle body gasket to make certain there are NO vacuum leaks.

Then run the engine again with the same binary. Also have a factory binary for the Vortec with TBI for export trucks. May try the latter binary later.

I have NEVER seen a GM throttle body that did not have an adjustment screw. Both of my 2" bore TBI units had capped off adjustment screws.

[brian617]

Also have a factory binary for the Vortec with TBI for export trucks. May try the latter binary later.

As far as I remember that "Vortec/TBI/Export" .BIN floating around is a hoax. I compared it with a BJYL .BIN and found no differences in the fuel and spark tables.

[Fast355]

As far as I remember that "Vortec/TBI/Export" .BIN floating around is a hoax. I compared it with a BJYL .BIN and found no differences in the fuel and spark tables.

Its not a hoax, just not much different. The Mexico trucks have larger injectors and the calibration is not even changed for them! I have pictures of the 96+ TBI Vortec engines in mexico with vortec accessories on them. Even the vortec timing tables are not that much different than the TBI. My Vortec engine really woke up after adding timing to it. I added 12*+ in some areas without running into knock on 87 octane. In some areas I gained over 40 ft/lbs of torque.

[brian617]

I'll have to open those .BINs again and look, but i'm almost certain I laid the two maps on top of each other in graph mode and there was no difference. I manually added a vortec table in and it was seriously different shape. I've seen the pictures too, but the proof was in the pudding, I saw no differences. Didn't think to compare the AE stuff though.

[Fast355]

I'll have to open those .BINs again and look, but i'm almost certain I laid the two maps on top of each other in graph mode and there was no difference. I manually added a vortec table in and it was seriously different shape. I've seen the pictures too, but the proof was in the pudding, I saw no differences. Didn't think to compare the AE stuff though.

The $63 .bin is an Export Vortec TBI 350 calibration. The spark map has a few changes at high rpm and IIRC the base timing was set at 6*. They also have larger injectors than the normal 61s. IIRC they have Pink/Green painted markings rather than the normal Orange/Black 350 injectors.

[brian617]

The $63 .bin is an Export Vortec TBI 350 calibration. The spark map has a few changes at high rpm and IIRC the base timing was set at 6*. They also have larger injectors than the normal 61s. IIRC they have Pink/Green painted markings rather than the normal Orange/Black 350 injectors.

The only export .BIN I've ever seen is BRDW and the spark map is a dead ringer for BJYL, with only a few changes on the VE table. I suppose the added base timing and larger injectors would explain that.

[rsicard]

Gentlemen: Is there a way to expand the ADX file to see some more parameters being sent from the ECU to the ALDL? Would be nice to see open/closed loop. Also MAP values. At present, not interested in the transmission parameters until such time as it is installed in the 1995 C1500 pickup. Downloaded DataMaster to use and it has closed/open loop indication. Whether or not it works with this 0D mask, 16197427 ECU loaded BJYB binary, don't know as of yet. Sure would be nice to see the important parameters for right now with TunerPro RT version 5.x and be able to emulate the EPROM and adjust the VE tables as necessary open or closed loop. Reminder, I am a relative newby at this game.

The other vehicle with 16197427 ECU is a 1994 454 (Now 489 cu in) with Edelbrock peanut port intake manifold (because it was designed for GM peanut port heads) which has Magnetti Marelli Pico 29 pph injectors for the 502 GM engine. The similar Edelbrock TBI to (batch, bank to bank injection?) MPFI is the kit with 19 pph injectors for the 454. Chose the 29 pph kit as it is closer in displacement to 502 cu in kit. On this engine, I bumped up the ignition timing and got a hell of a lot more performance from it even without ECU hardware mods or serious re-tuning. Still passed Arizona emissions!

[brian617]

Gentlemen: Is there a way to expand the ADX file to see some more parameters being sent from the ECU to the ALDL? Would be nice to see open/closed loop. Also MAP values. At present, not interested in the transmission parameters until such time as it is installed in the 1995 C1500 pickup. Downloaded DataMaster to use and it has closed/open loop indication. Whether or not it works with this 0D mask, 16197427 ECU loaded BJYB binary, don't know as of yet. Sure would be nice to see the important parameters for right now with TunerPro RT version 5.x and be able to emulate the EPROM and adjust the VE tables as necessary open or closed loop. Reminder, I am a relative newby at this game.

At the top center of TP5 should be some icons "data dash, data list views, data history tables and data monitors". Clicking on data dash will give you a simulated dash with many options of data to stream. Right clicking on them will enable you to change what you see and where. Takes a little while fumbling through it before you get a dash set up the way you like it.

[rsicard]

At the top center of TP5 should be some icons "data dash, data list views, data history tables and data monitors". Clicking on data dash will give you a simulated dash with many options of data to stream. Right clicking on them will enable you to change what you see and where. Takes a little while fumbling through it before you get a dash set up the way you like it.

Brian617:

That is very true. On the right mouse click drop down list, closed/open loop and MAP are not on that list. Is there a way to expand the ADX file so that additional parameters are on the list? Please advise. Thanks.

[rsicard]

Its not a hoax, just not much different. The Mexico trucks have larger injectors and the calibration is not even changed for them! I have pictures of the 96+ TBI Vortec engines in mexico with vortec accessories on them. Even the vortec timing tables are not that much different than the TBI. My Vortec engine really woke up after adding timing to it. I added 12*+ in some areas without running into knock on 87 octane. In some areas I gained over 40 ft/lbs of torque.

This is really helpful information. Thanks much.

[rsicard]

I have the 350 Vortec running. Periodically at idle, the RPM starts to fall off then picks back up again. Comments please on this aspect.

I am wondering where the ECU gets its injector pulse width values when at idle in Open Loop mode? Is it that the engine must be warmed up, in Closed Loop Mode, and then capture the BLM History values in the on-idle table and then correct them near a value of 128. Once that is accomplished as well as correction of off-idle closed loop BLM values, then when the engine is cold at idle, it relies on the new on-idle BLM values? Is this true or is there some other MAJOR factors governing injector pulse width when on-idle, open-loop and cold coolant temp modes? Any thoughts on these aspects would be greatly appreciated. Please advise. Thanks.

[rsicard]

As far as I remember that "Vortec/TBI/Export" .BIN floating around is a hoax. I compared it with a BJYL .BIN and found no differences in the fuel and spark tables.

Look like I should switch over to the BJYL binary for the Vortec/TBI/ Export, or similar binary, to be closer to the objective of tuning the Vortec with 454 throttle body and Cop Car injectors. Then set the fuel pressure regulator to approximately what it needs to be and electronically tune from that point.