Dan Wendling

I have had the Katech splitter / undertray with fascia reinforcement installed now for a few track days and have noticed that the front fascia (bumper cover) is pulling away from below the headlights and connection to the fenders. When I was at Watkins Glen last week I noticed one other car with the same issue. Seems like it started when I was at VIR running with temps above 90.

Wondering if anyone has a modification to add additional support to help hold the fascia in place.

Katech_Zach

I think this is evidence that the Katech splitter with undertray is producing some serious downforce and when taken to very high speeds we're starting to see the other weaknesses of the car. I don't see this on my car but I have gone only 140mph. As you go faster and produce more and more downforce we may see this more. Also you note high ambient temperatures which may affect the plastic's rigidity. Maybe if there are enough track guys interested we could produce a more rigid and lighter carbon fiber front fascia with reinforcements in all the right areas. That is a large and complex mold though so the mold cost would be quite high. Considering the possibility of low production numbers mold amortization may make the part quite pricey. I would be interested to hear how many people would be interested in a part like that.

dvandentop

same problem here with front splitter installed, have ran road america a few times with speeds up to 160

Dan Wendling

Jason:

I think there should be a much less costly solution than what you propose. The parts are intended for use at speed and at normal track day temps.

What about an adjustable support rod that ties the re-enforcement and/or the splitter itself into the steel bumper or frame?

I was really asking what solutions others have found.

Everett Ogilvie

, and folks should not be surprised to see various new impacts at higher speeds. I definitely found some new issues/symptoms on my car at the speeds we hit at Road America and Miller Motorsports Park. These issues are often physical phenomenon caused by the forces generated at higher speed including but not limited to; part damage/deformation/breakage etc. (I already put in place a fix for a specific issue found with my car at speed).

John Shiels

I would be looking to brace it somewhere on the interior.

Falcon

Here's what we did on my C5 to hold the splitter. We welded a bar to the side rails and curved it down so that the splitter supports could attach to that and take the force off of the plastic fascia.

Kubs

This is exactly what I would do! The force needs to go to the frame instead of flexing the plastic/urethane bumper.

Dan Wendling

Bump

Looking for more solutions

RichieRichZ06

Do you have the fiberglass reinforcement behind the front fascia already installed?

Dan Wendling

Fiberglass reinforcement installed as mentioned in OP.

davidfarmer

the C6 fascia is really soft, supported very little by the bumper and foam crush structure. The reinforcement helps keep the bottom lip from bowing as much, but doesn't support the upper part of the fascia any. You can always get a carbon fascia from ACP, or maybe we should just glass-reinforce the entire inside of the OEM fascia.

Dan Wendling

Still looking for more solutions.

Gman57

with you.... I'm in the process extending the ZR1 splitter with a full undertray, this is a real consern to me too. Anyone that has a good mount for the undertry please step up and show us your stuff

longdaddy

2 eyebolts into the front frame piece, each with a steel cable (optionally with length/tension adjustment) connected to the front of the undertray under the headlights - or at least as close to the front as possible - another eyebolt with a really large washer or maybe even a reinforcement plate on the bottom to distribute the pressure. you will need to find a "line" to route the cables so they do not put pressure on anything that's not a solid metal or drill through stuff that's on the way, like brake ducting etc - sorry not up do date on the guts of C6 bumper . If anyone has a pic of the front of C6 with a bumper off, we can figure it out from there.

I bet you can keep all the redneck engineering invisible once the bumper is back on


fun weekend project with anything you would need available at a hardware store.

this is actually how the front splitter/undertray piece is secured on the ACR and the tension adjustment lets you control the angle - both simple and effective.

Falcon's solution would be a really neat (and the right) way to do it, but too much work/fabrication for my attention span...

EDIT: btw, for this to work, I am assuming the rear part of the undertray is mounted to something relatively unmovable (I see that there are 2 bolts/rivets from a photo on Katech website, but cannot see what they connect to). If not, then by creating securing the front, you may cause the rear of the undertray to deflect downward, which could "straighten" your front fenders more than neccessary

dfinke23

I am not familiar with how Katech's undertray is attached to the their splitter. If it is solid, and it attaches to the radiator bracket, it will reduce the flexing and give some additional support.
I personally think a multi-piece design is inherently weak, but can be made ok if the fasteners are laid out properly.
I am disappointed in some of the responses you are getting. You are using the splitter how it was meant to be used, you weren't given any kind of "DO NOT USE ABOVE 150" disclaimer, and it is causing a problem. There are a lot of vendors selling this part, it would be nice to see someone take the lead and figure it out.

Gman57

Your right on the money

Katech_Zach

Here is my suggested solution for you. I recommend that you drop an L-bracket down from the frame to the undertray in a more forward location than our undertray-to-radiator support backets. There is a perfect location that is just inboard of the brake ducts and just outboard of the radiator frame. You can pick up the longitudinal frame rail there and drop it down to the undertray. Make sure that the bolts that go through the undertray have large washers on each side and are not tightened too much to the point that they compress the honeycomb sandwich of the undertray. Our other undertray mounting points have small reinforcements built in to prevent this.

Katech_Zach

Our multi-piece design is not weak. We've tested it up to 180mph.

Dan Wendling

Thanks Jason but that is only part of the issue, and I had planned on something like your suggestion to stiffen the trailing edge of the under-tray.

The larger problem is that the splitter under-tray combination provides so much down force at speed that is pulling the front fascia (bumper cover) away from the headlight and fender. In my case this is now a gap of about .25" at rest. It is very easy to see, simply placing my foot on the splitter by the brake duct opening and applying a light pressure I can see the fascia pull away from the resting position.

One of the posts in this thread hit on the real issue. The consumer is expecting a complete product, not one where additional custom fabrication is required. Drilling a couple extra holes or trimming some material away is a reasonable expectation. But needing to engineer and manufacture the missing parts is in my view not something the consumer should be expected to perform.

PS> I do have the fiberglass re-enforcement installed behind the fascia opening.