Just did it to my buddy's new XR4 (with a ~$250 White Bros E pipe); what a difference! As for the pipe, we compared performance between another new XR4, with the same mods and a ~$75 vortip. We all felt the performance gain was noticeable enough to be desireable. Whether it's worth the ~$175 cost differential is your call. BTW, both exhaust changes were reasonably quiet; important to our group.
No special tools needed for the jets. A manual is a good idea though.
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Noscitur ex socio, qui non cognoscitur ex moto artem
[This message has been edited by mtngoat (edited 04-13-2001).]
[This message has been edited by mtngoat (edited 04-13-2001).]