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2002_z28_six_speed
March 11th, 2021, 06:55 AM
I am starting up an ls swap into a vintage car using an LQ4 Gen 3 and 4L80. At this point the wiring harness and PCM has not been chosen.

My 1st question is there any 1MB PCM with cable throttle?

My other question is there any limitations on the older 512 mb PCM that i may not immediately realize:

is far as fuelling calculations capability or deficient operating systems should I even care about getting a 1MB PCM or are they pretty much the same. I would hate to go 512 and then realize it cant handle as much airflow or is harder to tune.

ScarabEpic22
March 11th, 2021, 09:17 AM
1) Yes, Express Vans and S10+Blazers use DBC setups. All you need to do is obtain a specific PCM service number that has the IAC drivers to work with a DBC setup and enable the bit in Platform Options.

What is your setup and future plans? Staying NA, going turbo/supercharged, N2O, what fuel(s), so forth? Airflow/tuning is identical between the 512kb and 1MB PCMs, need to understand more what your uses are then can recommend a route.

512kb PCMs only have 1 OS that is FlexFuel compatible, 2002 used in Tahoe/Yukons IIRC. That particular OS doesn't have a Custom OS available, so you cannot run true FlexFuel + Boost on a 512kb PCM unless you do separate tunes for separate fuels. If you don't need FlexFuel capability, the 512kb PCM has the best EFILive COS available using the 2002 'universal' OS 12212156. 1MB PCMs have a few COS' available from 03-05; 06-07 OS' do not have COS' available.

joecar
March 11th, 2021, 09:54 AM
+1 on what Erik said.

OS 12212156 is very versatile in terms of COS5 and 4L80E.

2002_z28_six_speed
March 27th, 2021, 12:44 PM
1) Yes, Express Vans and S10+Blazers use DBC setups. All you need to do is obtain a specific PCM service number that has the IAC drivers to work with a DBC setup and enable the bit in Platform Options.

What is your setup and future plans? Staying NA, going turbo/supercharged, N2O, what fuel(s), so forth? Airflow/tuning is identical between the 512kb and 1MB PCMs, need to understand more what your uses are then can recommend a route.

512kb PCMs only have 1 OS that is FlexFuel compatible, 2002 used in Tahoe/Yukons IIRC. That particular OS doesn't have a Custom OS available, so you cannot run true FlexFuel + Boost on a 512kb PCM unless you do separate tunes for separate fuels. If you don't need FlexFuel capability, the 512kb PCM has the best EFILive COS available using the 2002 'universal' OS 12212156. 1MB PCMs have a few COS' available from 03-05; 06-07 OS' do not have COS' available.

Things have been going super slow over here. I can't believe its taken me so long to respond. I do appreciate the sanity check. I grabbed a stand alone harness correct for a 2002 vehicle and I am looking for a PCM out of a 2002 Camaro or 2002 van right now.

I think I am going to run a pretty stockish setup out of the gate just to get everything working and prove it is all sorted out. After that I am going to take the maggie off my truck and put it into the project vehicle. I don't really need boost in my DD truck.

Originally I was going to do a turbo or supercharger project on the legacy engine with a blow through carb.