A 3.5 should be safe, but you really should scan for KR. The 2000 plus tend to run more lean and can see KR sooner. The headers are nice, but don't help a whole lot unless you put rockers or a cam in. The engine will only breath as good as the most restricted spot, and that'* your valves. Don't look as much at pulley size. You want to run the most timing you can with the smallest pulley. No less then 15*, but really no more then 20* or so. And that'* where a good tune comes in.
SAVING THE WORLD ONE BONNEVILLE AT A TIME
1997,1998,2000,2005 year confused Bonneville SSExi. Stock? ish.
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