I have searched a good bit an can't find a straight answer. I thought that the SI rotors were 10.2" and the stock CRX rotor was 9.5". I was at work and pulled a rotor for an SI and it measured 9.5". I double checked the part number and it was correct. What is the deal? I thought the SI had better brakes than the regular CRX.

 

88-91 CRX SI's have 9.5" front rotors. The 90-91 civic EX has the 10.2" rotors

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 95 LS &raquo;</TD></TR><TR><TD CLASS="quote">88-91 CRX SI's have 9.5" front rotors. The 90-91 civic EX has the 10.2" rotors</TD></TR></TABLE>

ditto

 

Then what is so special about the brake setup on an SI? Is it because the caliper has a larger piston compared to a regular civic caliper?

 

The reason that the SI front knukles are wanted is for the reason for fitting other axles when doing swaps. I hope that is what you are looking for!
Daka