High Temp Paint on Exhaust

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Guacamole
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High Temp Paint on Exhaust

Post by Guacamole »

Well now that most of my exhaust is on its last legs & is currently held together with what amounts to a duct tape fix (pic below), I'm currently browsing around for relatively cheap replacement parts. A full OEM exhaust runs about $2600, but I've managed to find a full exhaust replacement for around $500-$600 depending on which parts I get. I got a price estimate for a professional weld job to fix the flanges & holes for around $350... so a an entire new exhaust for a little more money the seems like the better option. Problem is though, most of these replacement parts look like they'll last only a couple years out here in MD where the state highway admin FREAKIN LOVES SALT. [smilie=hate.gif]
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So, anyone have any experience using high-temp heat spray paint on their exhaust? Looks like a viable solution, but section 8-5 of the owners' manual says don't do that... but it's under the turbo models section. "Do not apply undercoating or rust prevention treatment to the heat shield of catalytic converter and the exhaust system."
http://www.scoobytruck.com/pdf/2006_baj ... manual.pdf
However, this post on Subaruforester says it can be done, even on a turbo.
http://www.subaruforester.org/vbulletin ... ost6006289
So what gives; can it only be used on the midpipe & muffler on the turbo models? Anyone done this before?
Paint I'm potentially using: https://www.amazon.com/dp/B003CT4AKC/_e ... J8V3&psc=1

Also in case anyone's interested, here's a list of the potential parts (NA only):

-Headers (undecided)-
Borla knockoff UEL: https://www.amazon.com/dp/B00JA1C4MM/ (best value but I don't want to remove the rock guard, also concerned with oil filter access)
Bosal EL: https://www.amazon.com/dp/B0049AZDTA/
Mac EL: https://www.amazon.com/dp/B015WP1UF6/
Walker EL: https://www.amazon.com/dp/B001BS5XQQ/

-Cat Pipes (undecided)-
Walker OEM copy: https://www.amazon.com/dp/B001AGT39M/
Unknown manufacturer (cheapest but sketchy): https://www.amazon.com/dp/B0773LXNRQ/ (Ebay listing with reviews: https://www.ebay.com/itm/1999-2006-Suba ... 2043022413)
Xotic custom: https://www.amazon.com/dp/B075C45GT3/ (seems best value but no reviews, also can't find an Ebay listing, sketchy)

-Midpipes (undecided)-
Walker: https://www.amazon.com/dp/B000CLN18U/
Bosal: https://www.amazon.com/dp/B0049B5AQ0/

-Muffler-
Bosal OEM copy: https://www.amazon.com/dp/B0049AZ2B4/

-Other Stuff-
Mid-to-Muffler Gasket: https://www.amazon.com/dp/B001AX82VK/
Hangers: https://www.amazon.com/dp/B016AX887C/
Flex Joint gasket: https://www.amazon.com/dp/B000C2AEES/

All help appreciated!
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kamesama980
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Re: High Temp Paint on Exhaust

Post by kamesama980 »

You're right, the replacement parts will definitely rot out in a few years. That's the price difference: the stock system is stainless or near enough and lasts a lot longer (in my case, 150k miles/15 years with a few pinhole gasket leaks). so 173/year for OE($2600/15) or 150/year ($600/4 years). both figures ignoring repairability.

Have you checked RockAuto? looks like they have a kit from Bosal that's the *whole* exhaust and RA has excellent cust service and 5% discount codes available about everywhere. add the cheapest cat and it comes to 550 shipped for me. I have prime but I'll buy car parts from RA all day long unless it gets to be 25% cheaper elsewhere. less sketchyness and dealing with multiple retailers and knockoffs and who knows what.

As for the paint, the main thing I'd worry about is any paint will raise the cost. The better the paint, the more costly. yes it'll help and I wouldn't worry about the subaru warning in this case. the reason behind it is that they spent a hefty chunk of change on emissions testing and material longevity of their parts. anything you do to it means they have to argue if there's a warranty issue. the two issues I see with painting is it could increase temps in the cat by retaining heat (not likely enough to notice though) or unpleasant odors from it burning off in a 1200+f environment. I've done it before and it absolutely helps on the pipes but the problem, as in your case, is the joints and water in the exhaust gas. Also, the car I did it to is a summer track toy, not a winter DD. winter ice, snow, salt, brine may just strip the paint off like a sandblaster.




side note, saw this on the checkout page under the cat:
"Center; For Vehicles With California Emissions Only;(Not legal for sale or use in California; Not legal for sale or use in New York for vehicles with CA emissions)
Oxygen (O2) Sensor(s) should be inspected or replaced whenever replacing a catalytic converter.
Davico recommends cleaning your exhaust system with Sledgehammer to extend the life of your new catalytic converter. "
-Russell
"You don't get to judge me for how I fix what you break"
03 sport 5mt
05 turbo 5mt vf39 and other STI bits, 3" turbo-back
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Guacamole
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Re: High Temp Paint on Exhaust

Post by Guacamole »

Well shoot... guess I'm SOL. I never saw the full kit until I opened the 03- why don't they have that kit listed on all the NA model years? Anyway, the whole thing's hanging by a thread from the cat back & the cat flange is toast so either way I'm going to have to bite the bullet eventually. Guess I'll just have to start saving & see how long the paint hold up in the grinder! Thanks for the info.
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kamesama980
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Re: High Temp Paint on Exhaust

Post by kamesama980 »

Guacamole wrote: Tue Feb 06, 2018 12:39 pm Well shoot... guess I'm SOL. I never saw the full kit until I opened the 03- why don't they have that kit listed on all the NA model years? Anyway, the whole thing's hanging by a thread from the cat back & the cat flange is toast so either way I'm going to have to bite the bullet eventually. Guess I'll just have to start saving & see how long the paint hold up in the grinder! Thanks for the info.
What year is yours? I only used 03 because mines an 03 and you didn't say what yours was. The heads are different (among other things) from the EJ251 to the EJ253 so the 03 manifold may not fit on later engines. Then again it may just me the 02 sensor is on this side instead of that side.

I have a welder and I'm just good enough to be dangerous so the whole conversation is academic to me lol. I did work in a shop and parts store while going to school for auto tech so I've played with the whole and piecemeal systems too.
-Russell
"You don't get to judge me for how I fix what you break"
03 sport 5mt
05 turbo 5mt vf39 and other STI bits, 3" turbo-back
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Guacamole
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Re: High Temp Paint on Exhaust

Post by Guacamole »

06. I thought the difference between the 251 & the 253 were just around the new MAF sensor & intake manifold? This is all from literature, no experience so I'm probably wrong. The FSM for the 06 Baja just reuses the exact same guide & diagram from a 98 Legacy, & the 03-05 parts index says the manifold assembly (44619aa00a) fits for all model years, but Subaru parts only lists this for the 04-06 and a different assembly with 7 different part #s (44109AE031; 44101AC010; 44101FA030; 44101FA041; 44101FA050; 44109AE030; 44109AE04A) for just the 03s????? but they list the 03 part as compatible with the 1.8L & 2.2L engines?????????????????
03: https://parts.subaru.com/p/Subaru__/EXH ... AE031.html
04-06: https://parts.subaru.com/p/Subaru__/EXH ... AA00A.html
WTF and my 06 manual says my engine is a 251, and so does the 06 manual in the library????????????!?!?!?!?!?!?!?
I think I'm going insane.
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kamesama980
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Re: High Temp Paint on Exhaust

Post by kamesama980 »

I know the wiring and whole engine management is different between the DBW and mechanical throttle by necessity. I thought the DBW engine changes also included cam timing? Doesn't matter.

The different wording and listings may be a matter of revisions (or lack thereof): at one point, the same manifold was compatible or was planned to be. Later, the design may have been revised for any of a thousand reasons and backwards compatibility was never verified nor was the old listing updated
with the superseding part number. That's the downside of the information and documentation society we have now: it's almost impossible to be sure everything's up to date. Could also be that there is some grey area and overlap where the old part does fit the new engine but the new part isn't backwards compatible. They aren't necessarily exclusive.

there are a lot of pages and diagrams to make in a service manual. The writers take all the shortcuts they can and frequently copy sections from previous models when they can (and occasionally when they should not).

Honestly, I'd get the stainless header over an aftermarket OE style manifold. Having used pipes from bosal, walker, etc their main concern is fitting the jig, not fitting your car or quality of manufacture. Their QC is more of a comparison looking at it from at least 10 feet away after a couple beers. There's a very good reason the actual OE part costs 5x as much.
-Russell
"You don't get to judge me for how I fix what you break"
03 sport 5mt
05 turbo 5mt vf39 and other STI bits, 3" turbo-back
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Guacamole
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Re: High Temp Paint on Exhaust

Post by Guacamole »

Yeah, I've been thinking about it & OEM is probably the better choice than the crappy knockoffs. I've got the timing belt coming up in another 9k miles so hopefully I'll have enough saved up to get it done along with that by then.
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