PI heads on 98 gt?

[extra manish]

What do you need to do when putting PI heads on a 98 gt? I heard that the chamber and pistons are different on the 99 and up. What will happen to the compression ratio?

 

[Yellow4.6]

What do you need to do when putting PI heads on a 98 gt? I heard that the chamber and pistons are different on the 99 and up. What will happen to the compression ratio?

All you need is the swap kit and the other supporting parts (do a search on the topic). Yes the compression does jump quite a bit, some say between 10:5:1 and 11:1. Reason for the bump is because the 98 slugs are flater than the 99-up slugs and the valve chamber is slightly different.