c5ls1vette

iTrader: (6)

I have noticed in tuning a couple of cars (with LS1 Edit) that the cars that are 01-02 idle extremely well with big lift cams compared to the 99-00, (or maybe it is just me). I have also noticed there are more information in the factory tables (01-02) than there is in the (99-00) tables. I was having the hardest time trying to get the surging out of a 99 TA and no matter what I tried it would not come out. I then put a 2001 pcm in the car and tuned it the same way I did the 99 and the car idles perfectly.
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foff667

iTrader: (2)

there are more tables, more resolution in many of the tables, etc...obviously there were many mechanical changes as well from 99 to 02 so many of the tables have different values as well.

wait4me

iTrader: (10)

It would probabably be from the spark idle error correction?

c5ls1vette

iTrader: (6)

So, can GM program a 99-00 computer to the 01-02 tables?

SSpdDmon

iTrader: (10)

They can, but they won't. When the GM engineers issue an update for your model year that requires a dealer to reflash the PCM, I would assume they started from the last 'good' tune in their files for that model year. They would create more problems than they would solve if they loaded an '02 file into an '00 car.

squealingtires

iTrader: (14)

one has the 512kB cache and the other has the 1024kB cache? Are there fundamental differences between these two? How about processing power, sampling rate, optimization?

foff667

iTrader: (2)

as far as I know 99-02 were all 512kb...03+ is 1024 though

wait4me

iTrader: (10)

2003 corvette is still 512k right?

foff667

iTrader: (2)

I thought they were 1024 thats why RoadRunner requires a new pcm for 03+ vehicles? I'll double check though.

Doc

iTrader: (9)

I came upon a 03 ZO6 six months ago that had the 1mb pcm in it. I couldn't put my 512k RR in it. Different connectors. 512=red/blue 1024=red/green

wait4me

iTrader: (10)

looking at all my files, it looks like the 2003 vette is 512k

foff667

iTrader: (2)

yeah, looks like your right Jesse...guess its just a different connector issue.

c5ls1vette

iTrader: (6)

thanks for all of the replies.
Since the 2001 computer ran perfect in this car I have manually copied just about every table (in Edit) (timing tables, VE tables, etc) to the 99 PCM. Still have the surge. I put the 2001 computer back in again and it idles perfectly. There are just not enough tables in the 99 PCM. A buddy of mine works at a dealer and said he could flash the 99 PCM to a 01 PCM as long as I have the VIN number of a 2001.

again thanks for all of the replies.

wait4me

iTrader: (10)

I thought for the longest time that they where 1meg like the rest until i kept sending out the wrong pcms to customers for them. opps.

MrDude_1

iTrader: (4)

the hardware itself is identical between 99 and 02 fbodies... the OS itself is diffrent.

you can flash a 99/00 PCM to have the same OS as a 01/02... and the reverse is true too, if for some reason you wanted to go back...

squealingtires

iTrader: (14)

Back to the top. Why are there 2 different computer sizes (512kb,1024kb)?

wait4me

iTrader: (10)

More and more emmissions and stricter tollerences made it so they ran out of room in the 512k, The only option was for them to make the Flash hold more. every couple of years the size has gone up. Some computers use 2, 4 and even 6 megs out there.

Gordy M

iTrader: (2)

Several Corvette forums reported the early and mid 2003 Corvettes had the 512k PCM's and the later ones had the 1024K PCM, it was a running change in preparation for the 2004 C5.