They help but it's harder to launch unless you have a tire. For reference I went 13.3 @ 105 bone stock back in 02 and with the 4.30 and cai I did a 13.3 106. But to be fair the 2nd was into a 20 mph headwind.
I see and thats good to know, I am kinda kicking around the idea of selling my 01 and buying a termie. I got sticker shock after they told my how much $$ it was to set up new gears in that IRS.. I was formely/still am an MN12 guy which also has IRS but when I had gears done it wasnt that much cash.. were talking 800 bucks plus gears!!