Need help on 99 454, cant rev past 4800

[ScarabEpic22]

Dont know about the mount, and yes it is a table within the express van tune that you change.

[Chevy366]

VATS , Vehicle Anti Theft System , or something like that , G1201 if I remember right , <none> .

[Taz]

1999 Sierra / Silverado usually use LS1-B PCM service number 09354896. VATS parameters are found in G1201 - as indicated by Chevy366. VATS options are - None / PWM / Class-2.

If this is an engine conversion or “Hot Rod” then turning off the VATS is appropriate. If your 454 is still in the original 1999 truck, then you may want to consider leaving the VATS active, and configuring the PCM to link with the BCM (if they end up being compatible). This will keep your IPC completely functional - including the “Tow / Haul” indicator lamp (if so equipped).


Regards,
Taz

[hog]

Wow, I'm surprised that EFILive is so limited on the Vortec tuning. You actually have to swap the PCM to rev over 4800rpm. This is a software issue, not the PCM issue. These PCM's will support 5900rpm of rev limit, stock L31's 350's, 305 L30's are rev limited to 5600rpm stock, entering 6900rpm rev limits will still net you only 5912 rpm is the highest Ive seen on a blackbox. Kinda like the 7300-7400rpm hard limit of the LT1 OBD2 boxes.

If you swap to a 2000-2003 411 or the earlier 896 PCM, higher than 6000rpm rev limits can and have been attained with 305/350/454's.

I know of people that have L29 454's that have revved higher than 5000rpm, and they have posted in this thread, but tune with other software.

even if you are using the tuning software they and I are using, these PCM's wont allow for over 6000rpm rev limits.

I'm sure someone could wite a file for use with EFILive that could up the revs for this guy. A cax. file perhaps.

peace
Hog

[schwoch1]

Wow, I'm surprised that EFILive is so limited on the Vortec tuning. You actually have to swap the PCM to rev over 4800rpm. This is a software issue, not the PCM issue. These PCM's will support 5900rpm of rev limit, stock L31's 350's, 305 L30's are rev limited to 5600rpm stock, entering 6900rpm rev limits will still net you only 5912 rpm is the highest Ive seen on a blackbox. Kinda like the 7300-7400rpm hard limit of the LT1 OBD2 boxes.

If you swap to a 2000-2003 411 or the earlier 896 PCM, higher than 6000rpm rev limits can and have been attained with 305/350/454's.

I know of people that have L29 454's that have revved higher than 5000rpm, and they have posted in this thread, but tune with other software.

even if you are using the tuning software they and I are using, these PCM's wont allow for over 6000rpm rev limits.

I'm sure someone could wite a file for use with EFILive that could up the revs for this guy. A cax. file perhaps.

peace
Hog

Do you have a L29 big block file in HPTuners format? I have HP Tuners also, and I want to make sure that they have the rev. limit function for this particular cal in their software, just for my own well being. Last time I used HP Tuners for a Vortec black box PCM, there was damn near nothing to tune with there either!!!

Mike

[hog]

Do you have a L29 big block file in HPTuners format? I have HP Tuners also, and I want to make sure that they have the rev. limit function for this particular cal in their software, just for my own well being. Last time I used HP Tuners for a Vortec black box PCM, there was damn near nothing to tune with there either!!!

Mike

Sorry man, I dont use that software either. I use Tunercat OBD2, the old school version, not R/T Roadrunner equipped..theres a few hundred parameters/tables supported for each of the blackbox Vortec 4.3/5.0/5.7/7.4 engines 96-00.

peace
Hog

[schwoch1]

Sorry man, I dont use that software either. I use Tunercat OBD2, the old school version, not R/T Roadrunner equipped..theres a few hundred parameters/tables supported for each of the blackbox Vortec 4.3/5.0/5.7/7.4 engines 96-00.

peace
Hog

Yah, I wish TunerCat didn't sell out to JET, cause Jet's tech support sucks. I use TC non-OBD2 software for odds and ends, haven't used it in a while, not too much OBD1 stuff out their lately. I will say the user interface is not quite as user friendly as EFI Live or HP Tuners, but there are a ton of tables to be had!!! If used TC OBD2 cable and program were not so damn expensive and hard to get, I would consider getting it for myself also!!!

Mike

[pullincrazy88]

I have done the 411 swap with my L29 454 and actually am running a comp cams extereme energy set up with a set of there roller rockers also and ported stock heads. Idk if you have had time to do the swap yet but I promise you won't me disapointed! Even untuned the motor should feel more alive. Mine you could tell right after the swap that it sounded more alive and not so "flat". If you run into a non starting issue after the install and can here a clicking or power back feeding through the speakers with the key off you have to add two ground wires, one to each connector. I grounded one to the battery and one to the body. Can't remember which pin number it was right now though.