i currently have hks axle back which is 4.5 inch diameter opening and it fits nice. does this mean i could get a quad set up with 2 inch opening tips without having to cut/make fit with the bumper? also do you guys think double walled will clear it or will it add too much thickness? (2 x 2 in tips = 4 in which leaves .5 inch total for double walled size) maybe Going to go a different look if the cost of this will be close to cost of selling my axle back

thank you

 

it really depends on the shape of the tips that you use however if you take a look at the OEM tips that most "Quad exhaust tip" cars are, they are fake with a standard single but sometimes dual. Whether you do vertical or horizontal tips there will be some cutting of the bumper

 

You can get away with two 2" exhaust tips. However, the tips will look tiny and off as the bumper is cut for single tips. The best exhaust tip size would probably be 3.5" quads. I have my bumper cut and an aftermarket rear lip to fit 4" quad tips. Search on eBay. There's quite a few 2" quad tips that are double-wall with a 1/4 or 1/2 inch space in between the tips.

 

Could you share a picture of your setup? Im interested in how this looks..