Building a new bumper C7ZR1 on a C6Z

[Ronins2ndCuzzin]

It was a big day today. The official bonding was accomplished. Started by finishing (or at least trimming) the bumper support foam on both sides. Then on the table for the final "marriage"...had to rough up where the bonding epoxy goes to get good adhesion. Bond applied left to right. Screws are still there until the bond is completely set. This is where it will get good. The screws will stay in for the night, long enough for the adhesive to harden all the way. Then the sanding, body fill, and PRIMER are in the near term now!! Looking so forward to having this bespoke goodness on my ride. So far, I'm right at $2100 into materials for this. So worth it IMO.

[Ronins2ndCuzzin]

The screws are out! The sanding has begun! This is where it's really going to start looking like a finished part. I'm super stoked to be that much closer to primer.

[Steve_R]

That is going to look awesome.

[Ronins2ndCuzzin]

Made major progress tonight. The bumper foam has been finally shaped to 96% complete. After the next removal, we will finish the foam and give it a coat of panel black to freshen it up. This was one of the harder parts, that stuff is SUPER DENSE and very difficult to cut/shape cleanly. We had to use a combination of piano wire, hack saws, cut-off wheels, sanders, etc. And it took about 2 days of work. But man...it makes all the difference. When the bumper is installed all the way, it is ROCK solid. We're now to the phase of final installation. The majority of cutting, grinding, bonding, etc. are done. It's just down to trimming, priming, sanding, and then PAINT!

Thos with the keen eyes will see the tow hook and receptacle installed. The was fairly simple...after you get passed welding steel to aluminum.

[Steve_R]

Looking good! I wasn't aware the foam was that hard or dense, good to know.

I've done a lot of stick, MIG and TIG welding, but never tried to weld Al to steel. How is that done without making the Al brittle in the heat zone next to the weld?

[Ronins2ndCuzzin]

Originally Posted by Steve_R

Looking good! I wasn't aware the foam was that hard or dense, good to know.

I've done a lot of stick, MIG and TIG welding, but never tried to weld Al to steel. How is that done without making the Al brittle in the heat zone next to the weld?

LOL...it's not. I was trying to be funny. We're going to use aluminum plate and epoxy. Essentially like pictured below. The epoxy will be used to keep the receptacle from rotating, and the aluminum plate will be welded to the bumper creating a sort of cavity that the receptacle sits in. 1/8" thick 6061 should be plenty strong enough for this application. Debated going to 7075...but I couldn't justify the additional headache.

[Ronins2ndCuzzin]

While waiting for receptacle mounting parts, the smoothing and leveling has begun. This is about to get really good!

[Ronins2ndCuzzin]

It might not look like we did much...but we did. The receptacle plan changed slightly. We kept the full plate (minus an inch or so) and added that scrap length to the channel between the top and bottom of the bumper for structural filler and to aid in locating the receiver. It will also aid in keeping the plate from flexing too much if/when we do actually have to pull the car with it. We also finished the foam bumper support and painted the visible stuff. The picture doesn't give the best look at it, but when it's on the car, you don't see any of the upper part of it. We bonded the receptacle to the plate, and then the plate to the bumper support. JB Weld made that thing rock solid. We'll TIG weld it completely around the edges this week sometime. Unfortunately, we have to wait for more bondo as we used the last bit we had up to this point. We also trimmed and sanded the bottom of the splitter to line up with the rest of the car. That came out REALLY nice. Should be in primer this week!

[Steve_R]

Looking forward to seeing the finished product on the car.

If someone wanted this done what would it cost? I don't have a C6 any more, just curious...

[Rikki Z-06]

Originally Posted by Steve_R

Looking forward to seeing the finished product on the car.

If someone wanted this done what would it cost? I don't have a C6 any more, just curious...

[Ronins2ndCuzzin]

Well, you could go the Supervettes route (he sells a bolt-on version of this with a 6-8 week wait). When I looked into it, it was $3800 for the bumper, grilles, and splitter (not including taxes/shipping). That money did not include, prep, paint, and finishing (and you lose your bumper support foam). If you had to pay a paint and body shop for the labor to prep/paint/mount/blend, the specific cost depends on the shop. But expect at least 6-10 hours of labor and paint (but more likely 20-24 labor hours)...probably 1200-2200 depending. Due to the near $6-7K price tag for that, I elected to just make my own. I'll probably get this on the car for around $3K out the door. Granted, the labor between my friend who owns the body shop and I cuts WAY DOWN on costs. The materials we've used on making this will likely end up around $7-900.

So my options were spend 6-7K on a bolt-on that may/may not fit like I want, or made of materials I wanted...or spend ~$3K on a bespoke bumper that fits and finishes perfect and won't fail at speed or during driving. For me, the decision was a no brainer.

[Steve_R]

Thanks for the info. I've briefly considered putting a ZR1 front on my C7, but those are between $1k-$2k, not including labor and paint. I can do the work myself, including paint, but since I've already swapped the stock grill for a Z06 version, and installed a CF splitter I likely won't pull the trigger on a ZR1 front.

[Ronins2ndCuzzin]

That's a bummer. The ZR1 fronts really look quite spectacular in person.

[Ronins2ndCuzzin]

Foam mounted up after receptacle bonded. Next work will happen Wednesday.

[Ronins2ndCuzzin]

The receptacle for the tow hook is now permanent. We TIG welded the outer edges where welds would take. Everything else is epoxied and panel bonded. Paint will happen today or tomorrow. You won't even see it except for when the hook is installed. I know...the welds ain't the prettiest...but it wasn't an easy weld job either. More pics soon...

[BRUIZER]

That's awesome! It's going to look badass one-off when your finished.

I've got an external tranny cooler/fan behind the oem bumper where the fog light was. Gonna yank the other light to run an external oil cooler but sorta concerned how it will effect aero at higher speeds.

Looking forward to seeing the finished results.

Btw, if ya come-up with a better solution to swap-out the crappy lower rad support (I've broken three), Im in!

[Ronins2ndCuzzin]

Originally Posted by BRUIZER

That's awesome! It's going to look badass one-off when your finished.

I've got an external tranny cooler/fan behind the oem bumper where the fog light was. Gonna yank the other light to run an external oil cooler but sorta concerned how it will effect aero at higher speeds.

Looking forward to seeing the finished results.

Btw, if ya come-up with a better solution to swap-out the crappy lower rad support (I've broken three), Im in!

Got any pics of the broken ones? Now would be the time for me to come up with something...

[BRUIZER]

Originally Posted by Ronins2ndCuzzin

Got any pics of the broken ones? Now would be the time for me to come up with something...

I've since replaced it and scrapped the busted ones. Coilovers have helped, but I just try to avoid driveway aprons etc. It such a weak thin piece of metal with crappy welds to begin with. There was a guy selling reinforced lower rad supports, but I believe he's moved on.
May just have to find someone to fab-up something stronger. It's a pia removing all the added scavenge pump, cooler etc to replace it once a weld gives.

[Ronins2ndCuzzin]

Poll: Should I run C7 flags, or C6 flags on the bumper? The c7 flags are smaller and slightly more aggressive looking. The C6 are much bigger and flatter. I know some think it's sacrilege to change flag gens on vettes, but I've always been cool with it. Thoughts are welcomed here.

[Steve_R]

C7 flags.