DIY-ATNTFIU - Wrap Party: Putting exhaust wrap on a Mine's R32 downpipe.

With the exhaust on my Plymouth Horizon...umm, sorry, I seem to still be in April Fool's Nismo R32 GT-R in pieces while we fit together the new bits I thought I'd take a crack at cleaning up the Mine's downpipe that was on it.

If you're a dedicated import car fan you'll recognize the name Mine's. They're one of the most respected tuning shops in Japan and are well-known for both extremely capable tuner cars and eye-wateringly priced but top-notch quality performance parts. The GT-R is the marque most closely associated with Mine's and of course they make a wide range of upgrade parts for them. For the R35 they have everything from top quality carbon exterior pieces to fully-built motors. Since the R32 is a much older car Mine's doesn't support it as much anymore but one thing they still make are downpipes. As with anything Mine's though the downpipes are made in very small volumes so the price is high and lead times are long, up to a month for a downpipe. It was no surprise then that I was happier than a kid who was just told summer vacation was indefinitely extended when I peeked under my car and saw a metal plate with the classic Mine's logo affixed to my car's downpipe.
The very tasty Mine's R34 demo car. Image credit: Mine's

Once we got it off though it looked a little worse for wear – years of Japan's wet weather and the extreme heat from the turbo exhaust had sullied the once gleaming stainless steel. The exhaust piping is usually the lowest point on an R32 and so there were some scrapes on the bottom of the pipes. The sensor bung on one side was thick with rust to boot.
My downpipe was dingy from years of exposure to the elements.

The bung was absolutely covered in rust but the Mine's logo was still clear to see.

I wanted to keep the downpipe so I formulated a plan to make it look almost new again and at the same time improve its functioning.

Luckily I had some useful stuff that was left over from my R35's modifications. Back when I first started doing bolt-on mods to my younger GT-R I had the OEM downpipes swapped for larger AMS units. At that time I had used exhaust wrap on the new pipes and I still had some lying around. Why not give the R32's downpipes the same treatment?
These were my R35's AMS downpipes after a layer of White Lightning ceramic coat followed by exhaust wrapping.

If you haven't messed around with exhaust wrap before you've probably at least seen it on motorcycles and muscle cars and wondered what the point was. Well, exhaust wrap does several things. The main benefit is heat management. By insulating the piping it traps the heat inside so it doesn't affect other engine components or get into the car's cabin. Since downpipes often run near the footwells you can notice a big benefit in comfort by keeping your dogs from getting turned into Johnsonville Brats by engine heat. It can also improve exhaust performance since hotter gases theoretically flow faster and therefore will exit your exhaust more quickly. That principle may also be why eating a lot of chili makes you have fast-exiting exhaust gases as well, to the eternal annoyance of your friends riding in the same car.

Some people say wrap is a bad idea but mostly that's because of concerns about increasing the risk of corrosion. That's not an issue with stainless steel downpipes like my R32's Mine's unit or the AMS ones on my R35. Other people will say not to bother and use ceramic coating instead. Ceramic coating actually is better because of the greater coverage and thermal efficiency of the ceramic. For headers and turbo piping I definitely recommend coating over wrap because it looks better and protects the pipes better as well. I actually used both methods on my R35 downpipes but using ceramic requires extra time and much higher expense especially if you use a high quality motorsport coating shop like Swaintech who did my AMS pieces. For the R32 I didn't see the need for the added expense and time so I just did a wrap.

So how do you apply exhaust wrap? Well, it's actually really easy. If you've ever bandaged up someone you've got all the experience you need and this job will be a whole lot less bloody...hopefully.

You just need some basic materials – an exhaust part that needs wrapping, some exhaust wrap ( I prefer to use DEI Titanium that you can get from Amazon for about 40 bucks for 50 feet), some stainless steel ties or safety wire, scissors to trim the wrap, some wire cutters, and the wrapping skills you inherited from your past life as an Egyptian mummy-maker.
This is the basic stuff you need to wrap an exhaust pipe - stainless ties, a wire cutter, and exhaust wrap.

Before I wrapped my Mine's downpipe I had to clean it up a little bit. Spraying it with WD-40 and then wiping it down first with steel wool and then a rag took off most of the grease and grime.
It still doesn't gleam like new but at least the worst of the grime is off.

I then took a rotary tool with a polishing bit and started grinding off the thick layer of rust that had built up on the welded bung. I hit it with a steel wire brush attachment afterwards to further clean up the bung as well as shine up the Mine's nameplate. A couple of coats of Loctite Extend then sealed the remaining bits of surface rust on the bung and should protect it from further corrosion.
The bung and plate are looking much nicer after some polishing.

Once that was done I could start getting my downpipe to do its best Imhotep impression. First you want to wrap a couple of rotations around one end of the pipe. You'll then secure those first loops by wrapping them in either safety wire or stainless steel zip ties. I have both in my toolkit but prefer the ties for ease of use and a cleaner look. You can buy a whole bunch from Harbor Freight for cheap.
Starting the wrapping process.

Some people recommend wetting the exhaust wrap first before applying for a better fit but DEI says that isn't needed for their Titanium wrap and it's more than flexible enough without the water.

After securing the first part you just keep wrapping the material around the piping, being careful to keep it as tight as you can and overlapping successive loops. Once you get to the end of the pipe you cut the tape and use another tie or more wire to secure it. There you go! That was easy wasn't it?
Here's one side done.

And all finished!

For a final touch that helps the wrap do its job and makes it more tidy I used some DEI Silicone Coating. It's a spray on high-temperature paint that helps keep the wrap in place and acts as further insulation. On the R32 downpipe I used aluminum color spray since it was bare metal. For the R35 I had used white because the ceramic coating underneath was that color.

This puts a nice finishing touch to your wrap. Image credit: DEI
My little "Shrine De Mine's". Actually I just clamped it to a workbench so I could have access to all sides for spraying.

Applying the first coats.

Once I was done with the wrap and spray the Mine's pipe looked pretty fresh. If you're doing exhaust work on your GT-R, it's worth considering this simple technique to improve your car exhaust's functionality.
The downpipe now looks much more slick than the dirty mess I had before.

And the Mine's logo can stand out proudly once again.

Important disclaimer: Understand that working on your car can be inherently dangerous. This is meant to be a guide only and does not take the place of common sense and proper safety precautions. Only you can ensure your own safety. Know your limits and ask for qualified help if you're unsure of something. Every time you act stupid in the garage...God kills a Miata.


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