Im using the Buku clutch and tuning a softer setting to minimize losing the rear on power, I can easily lose the rear end by being aggressive on power I have jp 1 and 4 and will try jp6 soon. I rather the off road pipes for their strength but I can always go to a nova 2015 in a pinch. I ran the car yesterday with my RB C11 and JP4 offroad pipe and car looked fast and felt good held idle well and never exceeded 220 degrees. I still need to get a couple more tanks thru but will make final adjustments on race day. Car usually looks good twice, when Im alone and right before I crash...