Since starting this post, I've been asked; "Is this actually worth doing ?"
Just thought I'd respond publicly so all can see an opinion and make up their own minds.
**Disclaimer**. Like with EVERYTHING ( cat converter removal, catch cans, slotted vs STD brake rotors etc etc ), everyone has their own opinions, and this is just mine on this subject.
Q: Is it worth doing ?
A: I wouldn't do it if I thought there was no gains, so in theory, yes.
Q: What are the gains ?
1. Keeps exhaust gases heated up so they flow more efficiently. You could up-size the exhaust but then you'll usually get drone.
2. Gasses are hotter when they hit the 2nd set of cat's and therefore the cats work better.
3. Slight reduction to under bonnet ( hood in USA / CAN ) temps.
3. Radiant heat is not directly exposed to the transmission / transmission pan. This only really applies when stationary.
The pipes run along side the transmission pan ( not close but if you're stuck in traffic on a hot day there will be heat transmission ).
Q: Are there any negatives ?
1. It can look a bit raggedy if applied badly, and in time it probably will start to look that way anyway, but will still work.
( But who cares when it's under the car right ? )
2. In very rare cases the extra heat can cause a crack to form but it's not common ( especially when the pipes have been heat cycled over ~1 year of car usage before applying ).
Q: Is it the best option ?
No. Ceramic coating is the best option for pipes BUT;
1. It's expensive compared to a wrap.
2. It works best applied inside and out of the pipe, and this can't be done on these downpipes unless you remove the guts of the 2'nd ( ceramic ) cats.
NOTE: A possible / probable bonus / side effect is that wrapping a complete exhaust would likely reduce drone ( for those that have it ).
In summary, it's your choice !
