1mean96ss

What are the main differences, problems, ect. i have a 98 pcm and harness for my swap but keep hearing that its not fast enough and has tuning problems. Im not trying to start a battle over tuning just want to know what the main differnece is and if i should try to get a 99+.

birdmaro

iTrader: (45)

if you can, get a 99+
0411 is the pcm

the 97-98s (ls1a) pcms have hindrances with their OS...not as many 'rows/columns' vs the 99+ pcms.

a good tuner should be able to work around it...without an issue.
the 0411 pcms also have the capability to use custom OS's via efilive .

95maroz28

iTrader: (21)

what your plans for the car? i agree a good tuner shouldnt have a problem or atleast mine didnt. i have a turbo 98 with maf but i think ill be swapping to a 99+ after new motor goes in.

98legendws6

iTrader: (5)

how can u change the vin# that is in the pcm? it has to match the body of the car due to inspection reasons in NC.

1mean96ss

mines a H/C/I car with a t56, 3.90s. Will prolly run a plate kit down the road with a 150/200 shot.

gearhead67

Good timing (for me) on this question. I picked up an ECM from a 98 Corvette (service number 16238212) for my conversion awhile ago, and just read today some comments about tuning issues with the 98s. I was searching the forum for more detailed information, but was struggling to find it. My plan is to build a fairly stock motor - 5.3L block and heads, Ls1 (or LS6) intake/TB and LS6 cam. So based on the comments in this thread, I should be OK with the ECM I have, right? Meaning, a decent tuner should be able to work with it for my application, right? I really don't want to shell out hundreds of $$ on another ECM if I don't need to -- especially since I have the wire harness that matches the 98 ECM. Thanks!!

Russ K

iTrader: (1)

Tuned several 1998 F-Body's & C5's without issue. No way would I hack up someones car by swapping a newer PCM.

If a tuner can't tune a 1998 pcm, then they won't be able to tune a 1999+ PCM either.

The 1998's only have a 2 bar OS available, so if you have more than 14.5 lbs boost it could be a problem.

Russ Kemp

gearhead67

Great news. Thanks Russ. Sorry OP for partially hijacking your thread. I think we were after similar info though.

1mean96ss

no problem, im just sticking with my 98 harness and pcm

Capricio

After doing a little research on 85mm MAFs, I learned a 98 PCM can not handle the frequency of the signal coming from one. Just thought I'd add that little factoid of trivia out there, too.