Hey, I just picked up an authentic polyurethane Kuruma Z front bumper for my G35 Coupe… fitment looks good, my only problem is that’s there’s waves near the bottom of bumper (where the intercooler is visible…I’ll try and get some pics today); but how do you guys deal with the waves in a poly bumper?

 

You would need to use filler and then block-sand to smooth it out before painting. If it's already painted there's not much can do....aside from repainting

 

Yeah, it's unpainted/untouched right now. Here's a shot of the bumper and the waves.

 

I see under your intercooler there are a couple threaded pieces on each end, you could possibly make 2 brackets that would bolt up underneath those and then have a piece of straight bar welded up to those and put 2 sided tape on the bar and your bumper?

 

I've used a heat gun to fix bits of bumper before.

While a good urethane surfacer would probably fill if blocked properly, I am not sure about the flexibility.

 

the problem with these bumpers is that they are flimsy, yes you can use some heat to rework bumpers but most of these polyurethane bumpers are hard to get a shape without some sort of reinforcement to hold that shape

 

Ugh, yeah that's not an easy one, and it looks like thin material in that area. Maybe you could bond a thin strip of aluminum to the underside of that area to keep it straight....then fill and block sand.

 

Good news! Concept Z Performance said that’s not normal and they’ll swap out the bumper for me!

 

heck yeah. Nice to see a place taking care of there customers.

 

take this from a guy whos been working in his dad's body shop since i was 12. When you get a body kit put on most shops (a good one) will build a bracket to attach to the bottom of your car and bumper to also reinforce it