Heatshield On Decat Pipe

[3LGODZILA]

i just made up a de-cat pipe today, just wondering if anyones welded a heatshield or something similar to disguise it as a normal cat. and does any1 know where i can get a heatshield from that i could just weld on myself?

i got the idea from looking at this pic, this is a proper cat but it looks like the heatshield is just tacked over the top.

[Johnny]

take it off the compliance cat, just unscews.

ready for flames????

[3LGODZILA]

haha, im already running a 'straight through' 2.5inch compliance cat, i only get a bang every now and then but i love it! the rest of the system is 3inch so i may aswell match it up. the de-cat i made is just straight 3inch pipe.

but yeah your cat must be different to mine, ive got 3 compliance cats at home, 2 of them are the same and have 4 nuts welded so a heatshield must of been bolted to it? i dont know but coz i received them like this. and on the cat that came with the car it has half a heatehield welded to the body of the cat (like in the pic above)

so i dunno ay i might have to find 2 half heatshields and weld them around the de-cat

[JiN_MaN]

You can but De-cat pipes that come with brackets on them to bolt your standard shields over the top. Looks just like a standard cat

Edited June 3, 2009 by JiN_MaN

[Chrisrotary]

Can i have one of your original/stock/compliance cats to make my own. make it easy for yourself wouldn't you just bash the core monolith out with a long screwdriver and hammer. instant de-cat. complete with heat shields. FYI some recyclers pay money for dead cats (catalytic converters) up to $60.

[Johnny]

Can i have one of your original/stock/compliance cats to make my own. make it easy for yourself wouldn't you just bash the core monolith out with a long screwdriver and hammer. instant de-cat. complete with heat shields. FYI some recyclers pay money for dead cats (catalytic converters) up to $60.

i did in fact do this on my 200sx, took a while cause the internals are tough so a hammer and a large iron rod was used lolz.

ps you will be surprised how much crud actually ends up in the bin

[bozodos]

Don't do it without a power drill, it took me 3 hours even with one and it was a hell of an effort (though mine had seemed to melt into aball full of gunk halfway down the body of the cat!)

I'd say a power drill with a spade bit or something like that! oh and be careful.

[mralbino]

Does a straight through cat add much noise?

With all that wicked cool power+flames , i dont know that i would care but would like to know none the less.

[DAS KAMU]

Can i have one of your original/stock/compliance cats to make my own. make it easy for yourself wouldn't you just bash the core monolith out with a long screwdriver and hammer. instant de-cat. complete with heat shields. FYI some recyclers pay money for dead cats (catalytic converters) up to $60.

yep in the u.k cats are being stolen from cars parked in malls and homes

very popular with the sudanese and nigerian chaps to make a few bob at the wreckers lol

when i tried to sell a few cats to wreckers in oz there like "who the f**k told you there worth money" lol

[TezGT-R]

Does a straight through cat add much noise?

With all that wicked cool power+flames , i dont know that i would care but would like to know none the less.

I doubt it matters much for your ride buddy, you need the car running to hear it.

Fix your damn GT-R already so we can show cameron why buying a fake evo is a mistake.

[bozodos]

lol well I've not noticed any flames coming from mine, just more smoke, and a LOT more noise!

[DAS KAMU]

i pop little flame poo's if i back off suddenly

my mate made me a great de-cat

i have to install a propper one for the new owner though

[3LGODZILA]

yeh i bashed out my 1st cat, took 1 hour with a stainless steel rod, hammer, and a drill with a big ass drill bit. f**k me alot of honeycomb shit came out, although it did make a noticeable difference, i was expecting a bigger power increase considering the amount of shit inside the cat. but it gave the car a more 'throaty' idle and you can also hear the turbo spool up louder, and also few hundred rpm quicker

[bozodos]

well decat turned mine from being a vacuum cleaner sounding POS which was struggling to boost until ~4500rpm and was sloooow as to a car which now lights up second gear and hits fullboost at ~4000rpm.

[R31Nismoid]

yeh i bashed out my 1st cat, took 1 hour with a stainless steel rod, hammer, and a drill with a big ass drill bit. f**k me alot of honeycomb shit came out, although it did make a noticeable difference, i was expecting a bigger power increase considering the amount of shit inside the cat. but it gave the car a more 'throaty' idle and you can also hear the turbo spool up louder, and also few hundred rpm quicker

I really hope you did it with a proper mask and didnt breath in the insides... being they are a carcinogen.

And it should take like... 10mins dude... an hour is lol

Anyway, yes, you can weld a shroud around quite easily. I might have known someone that did that with a 3.5" piece of pipe

OR

Get a dead 3" cat from a performance/exhaust shop and just interference fit a 3" pipe down the middle... 2nd option is easier

[bozodos]

Nice double post

well if you've not done it before, it can be a pretty labour intensive job (I also only had normal drillbits lol).

[Chrisrotary]

I used to work in an import workshop (left coz the owner was a dodgey knob head) and a guy came around every month or so and we sold him the ones we had to throw out because its part of compliance that a new cat has to be installed. Im surprised the wreckers don't this. I don't know where he was from or where he was going with them but from memory we were getting $50 - $60ea.

Should only take 10mins to de-cat a standard cat. Whats with drill? Hammer and long bar or screw driver should do it.

I have de-catted a hi-flow metal cat which was a lot harder because they are essentially one piece of metal mesh. I only did that because despite trying to explain to the customer that it was the real deal hiflow metal cat costing $400 or more he insisted he wanted emptied. Sigh.

So if it looks like cardboard rolled up in a spiral pattern on it end i would not recommmend bashing it out. difficult and a waste of a good cat.

Doesn't make massive power gains either (if its in good nick). and thinking that will reduce exhaust emmissions by 90% or so maybe its not worth it environmentally. (IM GUILTY OF IT) But maybe its something to think about as well.

[bozodos]

Coming to think of it mine may have been a metal cat - the insides kind of looked like ceramic or something coated metal, and yeah it had sort of shrunk to a mass near the back of the cat, and was also full of soot etc. I could barely bash the big screwdriver and chisel through let alone twist them around, and I had to drill holes next to each other before the guts would come out. I'm sure that it wasn't one of those $400 metal cats though, may have just been a high flow.