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Hello

The exhaust stain on my rear bumper has now become a issue since I have put a high flow cat on (crappy cat = no stain).

Having a white car I find myself spending to much time keeping it spotless.

The cat back is a Trust Power Extreme (angled cannon style).

I realise a ecu and a tune would help but I like the car stock for now - so im just looking at exhaust options.

Have the cat back shortened so end of pipe sits under car/ further out?

Different brands /styles of exhausts?

Custom down angled muffler?

Appricate any feedback / ideas / comments as this is just a small annoyance that I could do without.

Dan

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Hello

The exhaust stain on my rear bumper has now become a issue since I have put a high flow cat on (crappy cat = no stain).

Having a white car I find myself spending to much time keeping it spotless.

The cat back is a Trust Power Extreme (angled cannon style).

I realise a ecu and a tune would help but I like the car stock for now - so im just looking at exhaust options.

Have the cat back shortened so end of pipe sits under car/ further out?

Different brands /styles of exhausts?

Custom down angled muffler?

Appricate any feedback / ideas / comments as this is just a small annoyance that I could do without.

Dan

You meant the smoke that came out of your exhaust and stuck on your rear bumper? If you paint condition still good, before wash your car, just spray Engine degreaser over it first, that help a bit. Apart from that, if your car run rich, doesn't matter what style exhaust it is, you'd still get it.

The Jap use to put a bit of FOIL there for paint protection. Not recommend in Australia though.

Hello

The exhaust stain on my rear bumper has now become a issue since I have put a high flow cat on (crappy cat = no stain).

Having a white car I find myself spending to much time keeping it spotless.

The cat back is a Trust Power Extreme (angled cannon style).

I realise a ecu and a tune would help but I like the car stock for now - so im just looking at exhaust options.

Have the cat back shortened so end of pipe sits under car/ further out?

Different brands /styles of exhausts?

Custom down angled muffler?

Appricate any feedback / ideas / comments as this is just a small annoyance that I could do without.

Dan

Dan an ECU and a tune will not get rid of this problem. WRXhoon's white M-Spec gets the yellowing on the rear too and it is tuned well. I guess use a very mild polish every few months to clear it off but other than that you might just have to deal with it.

blind_elk = we only get BP 98 ultimate here in WA - so thats what I have to use.

Ronin - its not heat damage - its just exhaust residue. It comes off with polish back to new just shits me doing it constantly.

Sewid - looks like just have to deal with it.

Thanks for replys guys.

Dan

That what I sort of had in mind - a custom twin pipe slightly angled down - I recon it would look tuff as on the GTR.

But would it reduce the staining - who can say for sure!

Dan

this is very common wen ur not using a cat. but didnt know this still happens with a hiflow cat.

guess you gotta get used to it dude, unless you want to get some sort of dump pipe which is angled down? :)

Dan an ECU and a tune will not get rid of this problem. WRXhoon's white M-Spec gets the yellowing on the rear too and it is tuned well. I guess use a very mild polish every few months to clear it off but other than that you might just have to deal with it.

I get this canadian guy come round at work selling waterless car wash/wax stuff hard to explain , but i asked him about the exhaust stains and he said its ideal for the job makes it very easy to wipe off . ill get more details when im back at work its like 50 dollars a bottle or something but last for ages. it could be a soloution maybe?

Do your selves a favour and get rid of that 5" drain pipe since they are usually too short anyway.Don`t know why the Jap tail pipes are like this.Too big and too short.Anyway,replace it with a 3.5 or 4" but level with bumper.Haven`t had a problem since.Bumper is always clean.Any exhaust supplier will have some pipe lying around so get 10" of it then use an angle grinder to hack off the old tail pipe at the point where the new 3.5 pipe matches the reducer on the muffler.Do this yourself as it will usually be around $10 for welding.By cutting and trial fitting in your driveway you will do a better job than the muffler shop.Then unbolt the muffler and take it to weld.Oh,and take some rag to soak in water to drape over the muffler while welding so no splatter blobs on shiny muffler.

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