Body modification at exhaust exit

[Jimbo1965]

I have upgraded the 5.0 in my MKIII with a set of AFR heads. Looks like I need to remove about 1/4" of material around the cut-outs in the body where the exhaust exits due to the headers new positioning. The areas I need to rework is the "top" of the cut-out, and the edge closest to the door. Any recommendations for the safest way to cut the fiberglass on a painted body? I am not sure if this might be something that the average guy can do, or if it is more of a Professional's job. This is something I have never done before. Thanks!

[Jeff Kleiner]

I have massaged cutouts on painted bodies in the past using a 1 1/2" sanding drum in either a drill or pneumatic die grinder (the 1 1/2" is the perfect radius for the corners).

http://guideimg.alibaba.com/images/shop/108/03/23/9/ali-ind-354119-drum-sanding-kit-1-1-2-drum-sandr-mandrel_4553219.jpg

Since you sound a little apprehensive you might be more comfortable using the drill since it is slower. Lay a couple of layers of masking tape around the opening, mark out where you want to wind up and sneak up on it a little at a time. You should be fine!

Good luck,
Jeff

[michael everson]

What Jeff said. If your careful you wont even notice the paint missing. Just touch up the bare fiberglass with a matching paint sample.
Mike

[Jimbo1965]

So I just thought I would throw this in after the fact.
Before I did any cutting, I went under the car an closely studied the exhaust from end to end.
I stumbled on something VERY CRITICAL that I did not notice on the installation of my headers to the new AFR heads.
It turns out that when viewed from below the car, I noticed the excess material on the aluminum heads was not allowing the lower portion of the header flange to fully seat against the heads!
From above, all looked well!
Now, I am sure there would have been an audible report from the exhaust letting me know this upon fire-up, but I was happy to discover this beforehand.
So...upon several grinding, refitting, and grinding sessions (per header), I was successful in getting a correct seating of the header.
This also made a significant difference on the minor trimming that was needed for the retrofit of the AFR's.

I just wanted to throw this out for anyone who is doing a head swap and notices exhaust clearance issues.
A high-speed air saw made short order of the very minor trimming that was needed for clearance.
I used blue painters tape around the edges to be trimmed, and it came out beautiful.

[wallace18]

Also Breeze sells tapered shims that fix a lot of alignment issues as well. Glad it was something easy for you.

[Justinmk4]

Real quick question I have an MK four and I am installing a coyote I had the pre-cut oats done at factory five will the body need to be further trend where the side exhaust exits the body or can I go ahead and paint then mocked up the exhaust? All help is appreciated

[Jeff Kleiner]

All the cutouts (exhaust, roll bar, windshield, side louvers and lights) need to be massaged after chassis assembly/mock up and before paint.

Jeff

[mikeinatlanta]

For the sake of continuity with everything else he posts: What Jeff said. ;)

[mmklaxer]

Is there a reason to even get the cutouts vs just having them traced? If all the cutouts need tweaking, maybe money better spent on something else? Trying to understand the value of that option.

[mikeinatlanta]

I regret getting the cutouts, but others are glad they got them. Opinions will vary widely.

[Jeff Kleiner]

Is there a reason to even get the cutouts vs just having them traced? If all the cutouts need tweaking, maybe money better spent on something else? Trying to understand the value of that option.

Time vs. $$$

I've built a bunch of these for customers and prefer for them to have the cutouts done by FFR. Even though they have to be tweaked I don't have to spend the time doing the initial location. I have had to do some that didn't have the cuts done by the factory I can tell you that the time adds up. If you happen to make 'em too big you'll have even more time to fix it.

Jeff

[mmklaxer]

Makes sense; thanks folks!

[Greg Hoy]

Here is a video we just did on the Body Cut-Out Option. To me it is cheap insurance that it is done right. You do need to massage the cut-outs, just like the other panels on the body.

https://www.youtube.com/watch?v=JJ4dM4KlvMA

Greg Hoy
Factory Five

[GoDadGo]

Go slow and be careful. Having built boats (fiberglass) in my youth, it is far easier to remove material then to add it. Good Luck & Go Slow!

Also, on my kit I had Factory Five do the cut outs. Less itching plus time saved was worth the cost.