I’m about to install tool boxes in the skirt just behind the rear wheels. The left side will be over the exhaust pipe. How much clearance do you think it should have?
An exhaust re-route is another option to consider...Good question.....
I have plans for a generator box above my exhaust. I am looking forward to the replies.
What're you gonna store in it, and are the boxes metal, or plastic?
You might want to consider fiberglass cloth exhaust wrap. It's more for keeping heat in than preventing it from getting out (to maintain exhaust velocity for performance applications), but that's essentially two sides of the same coin. On an inline-4 you can hold your right on the collector 2' from the exhaust ports. So I figure in your application it would be more than sufficient.
Just an amazon search for reference. No endorsement of any of the specific products:
https://www.amazon.com/fiberglass-exhaust-wrap/s?k=fiberglass+exhaust+wrap
Header wrap has been proven to have far more cons than benefits and the benifits are neglible in the most extreme applications. If it's not on a full out race car, it has little to no benefit. I doubt heat from the pipe will be an issue.
Well, in the context of this discussion, header wrap has one important proven benefit - containing heat that could otherwise prove detrimental to surrounding materials.
The heat that I'm familiar with doesn't really understand whether it's coming from a 'full-out race car', or a medium-duty diesel. But maybe the heat is smarter in Georgia.
What's the temp surrounding the pipe? Or are you just guessing at fixes that may not be needed?
Probably do equally well, or even better, to put the wrap or other high-temp insulation on the box rather than the exhaust tube.
Or stick a piece of sheet metal in between as a heat shield. We see those all the time on/near catalytic converters and mufflers - no insulation at all.
On second thought, take a closer look at that picture. It looks as if the exhaust "tip" (can we call it that?) is joined to the exhaust tube about 1.5 feet back from the exit, and there's some air gap in there. The exhaust flowing past that gap will create suction and draw ambient air in at that point. It'll mix and the gases exiting at the tip will be cooler. I'll bet the exhaust tip is cool enough that nothing more is needed. Run it hard and then splash some water on the metal. Does it sizzle? Wet a finger and quickly touch the metal. Did you feel any heat?