2000 Seville STS
I have seen the pics and read the reports on the Cadillac STSi pace car. I know the main difference is that the heads have been machined so the compression ratio is changed from 10.0:1 to 10.45:1 and that the intake and exhaust ports have been machined to open the flow up a bit. I know I can have this work done myself on a set of heads, but my question is if I can order these heads from somewhere and if I do this would this create a problem with the OBDII computer in my 1997 STS. I live in St. Louis where the Gateway Clean Air Program is killing any performance modding around here. Thanks.