In the never ending quest to reduce the heat in my coupe: Has anybody tried wrapping the down pipes, and if so how has it worked out?
Never tried it but have also considered it. Another option, perhaps more attractive would be a ceramic coating.
I haven’t wrapped a Jag, but I’ve done a few cars. It does make a difference. I think the ceramic coatings are better looking (Wrapping looks ok (to my eye) on a pre war car).
Is it as miserable as people, say dealing with all the fiberglass itchies?
Having been a fiberglass fabricator, the secret is…
Cold showers. Seriously…
When I did, or do, work with fiberglass, I do it in shorts and a tshirt, because a Tyvek suit WILL NOT WORK.
Right after, I jump into a cold, COLD shower. Yes, you will SCREAM; yes, your pores will snap shut; yes, you will not be itchy.
I also soak the strips in water, which helps get them tight, and helps minmize the itchies.
Cold showers? No wonder you have so much time on your hands to post here!
Here are my stainless downpipes wrapped. I had no “before” experience with heat in an FHC, but I’m sure it had to help some with heat under the bonnet. Especially when the car was parked after a drive, keeping heat from flowing straight up to the underside of the bonnet. I also used DEI 2000 degree matting in the transmission tunnel to help even more. In the interior, I used Dynamat, then aluminum bubble insulation under the carpets. Even on warm days I don’t have a heat problem. I have AC but have yet to hook up the hoses, the only part of the system left to do.
Not so bad actually. I wore gloves but otherwise no special precautions.
The main thing is to learn not to scratch yourself, or wipe the sweat out of your eyes, or use the toilet…
Wetting it down helps, a bit.
I have used this product (though not on the E-Type). No itches or such, but I cannot compare its effectiveness to fiberglass:
Worked well enough for what I wanted (protecting an aftermarket sending unit from manifold heat). Six years later it still looks like the day I installed it.
I also added DEI 2000 degree matting on the muffler shields. One rivets to the body and the other bolts up and can be seen here on the floor before I riveted the matting to the panel. The matting is self adhesive but I used fender washers to help hold it in place.
Especially true, when using the old school carburettor cleaner.
Do not ask.
So the same precautions that apply when prepping the peppers for salsa.
I’ve wrapped mine for a distance of about two feet just below the flanges. That was about ten or fifteen years ago, and was due to the fact that the A/C hoses run right next to the exhaust pipes (great design, ehh?). I was afraid the heat would tend to crack the pipes (stainless) but so far, no problems. The hoses themselves are also wrapped, since they run right next to the exhaust manifolds.
In order to keep our big corporations prosperous, make the one percenters richer, and give the working class the artificial impression of prosperity, we require a small, controlled war in at least one country at all times.
Thanks everybody - it seems that wrapping is a viable solution. I’ve used ceramic coatings on my race car and there is a reduction in under hood heat, but it’s not that major IMO, and it’s gotten quite expensive to do. I’m about to pull the down pipes to install an adjustable torsion bar plate, so I’ll wrap them before reinstall. The advantage of just doing the down pipes is that they are all but invisible.
Not intended to create a totally new direction re: this Thread. I am wondering if wrapping the pipes has any negative effects? I.e, does the heat that is “locked” in create negative effects on the pipe, itself; Does the higher heat within the pipe travel backwards and have any effect on the exhaust manifolds or valves, or head, etc; Is there a negative effect on the mufflers, etc? I’ve rubbed against a lot of exhaust pipes over the years and I know they get very hot. Seems like manufacturers choose metal gauge and type for intended use and heat tolerances. I have no expertise in the area. Just seems like a reasonable thought?
Really good question.
A couple of questions:
Does wrapping “lock” the heat in, or does it move it down the pipe? I’ve only wrapped pipes well past the point where they were really hot . Am I right in thinking that this increases the thermal mass of the hot bit by something like 10-30%, and also increasing the radiant surface area (by moving the heat farther down the pipe)?
Wrapping exhausts is thought of as a performance enhancer. The theory being that if you keep the heat in the exhaust, as opposed to dissipating it though the down pipe walls, it will increase exhaust velocity in leaving the pipe, and provide an extraction effect. It seems well accepted in the hot rod world. It would move more heat down the pipe into the mufflers etc. I expect that the hottest area in the down pipes would be where the exhaust exits the manifold, and it cools down after that. I don’t think the wrapping will make it hotter than that point, but will retain the heat in the down pipes further along their length. In other words it won’t place greater stress on the pipes than that they experience at the entrance I suspect. The muffler will be hotter, which may affect any stuffing it has (if it has any like fiberglass or steel wool). I’ve never heard any body use the phrase “locked in” in relation to the wrapping. The purpose of the wrapping is actually the opposite - it’s to maintain the speed of the gas flow leaving. I’m just trying to keep the heat down in the car. I think a lot of heat in the car comes from the exhaust pipes under the car.
Now I have to ask.
I’m already weirded out by those automatic toilets which do the cleaning for you but… carb cleaner?
I did quite a bit of research on this before I decided to wrap the down pipes . The same amount of heat comes out of the engine but is directed and dissipated further down the system. The exact reason to use the reflective heat matting between the floorboard and mufflers ( the first chance down the system that the heat would start to dissipate), and the down pipe shield (which double shields the floorboards from the wrapped down pipes).
Two down pipes are about a hundred dollars. If I had to replace them every other year it is worth protection from the heat . To me, pipe failure is a non issue. Heat can be a big issue in an FHC.
Terry explains it very well.
I did something similar by fabricating a full width heat deflector panel (between the longitudinal rails). It’s cut from a sheet of 1/4" aluminum honeycomb. The entire exhaust system is ceramic coated (manifolds to tail pipes), there’s a lower heat deflector in addition to the one for the fluid reservoirs, and the entire transmission tunnel is lined with DEI heat pad.