DIY De-Cat
#1
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DIY De-Cat
De-Cat the cheap way
Tool's needed:
Bandsaw/Hacksaw
Angle grinder w/ metal cutting disc
Welder of your choice (I used a TIG)
2 x Vice-Grips
Vice makes things easier
14mm Spanners +/Socket set to take out the downpipe
Step 1:
Take off the turbo heatshield, take out the downpipe - 6 x 14mm bolts/nuts from the back of the turbo, and where it's connected to the centre section. Take out the Lamda sensor or disconnect the wiring from the engine bay near the boost solenoid.
Step 2:
Cut the downpipe, heatshields and all, in half
Step 3:
Rip out all the crap inside, I used a screwdriver and hammer to prise it out... and cut off the heatshields around the cat with an angle grinder...
Much better
Step 4:
Clamp the two ends back together... make sure you don't have it on back to front before you start welding
...and get welding
Step 5:
Paint, if you wish...
Galvinising spray:
High-temp Paint:
Step 6:
Heatwrap the downpipe and put it back on...
Step 7:
Do the same to the centre section silencer if you wish, I did, no pics though
Et voila
Tool's needed:
Bandsaw/Hacksaw
Angle grinder w/ metal cutting disc
Welder of your choice (I used a TIG)
2 x Vice-Grips
Vice makes things easier
14mm Spanners +/Socket set to take out the downpipe
Step 1:
Take off the turbo heatshield, take out the downpipe - 6 x 14mm bolts/nuts from the back of the turbo, and where it's connected to the centre section. Take out the Lamda sensor or disconnect the wiring from the engine bay near the boost solenoid.
Step 2:
Cut the downpipe, heatshields and all, in half
Step 3:
Rip out all the crap inside, I used a screwdriver and hammer to prise it out... and cut off the heatshields around the cat with an angle grinder...
Much better
Step 4:
Clamp the two ends back together... make sure you don't have it on back to front before you start welding
...and get welding
Step 5:
Paint, if you wish...
Galvinising spray:
High-temp Paint:
Step 6:
Heatwrap the downpipe and put it back on...
Step 7:
Do the same to the centre section silencer if you wish, I did, no pics though
Et voila
#3
nice job i was going to do that to mine but got a h&s downpipe so cheap i put that on on the end, would it not been a good idea to make it a open mouth while you had it off as that seems to cause quite alot of restriction, just an idea
#4
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It already was open mouth? As in there was no split in the pipe to begin with...
#7
Mick
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With almost no exceptions, aftermarket downpipes address this issue and allow a decent straightish flow from the wastegate (some use splitters to keep it separate for a short while, others don't). Therefore, whilst bashing the cat out of the standard downpipe will be an improvement, it won't be nearly as big an improvement as a replacement (or modified) downpipe with a proper solution for the wastegate. This is why people don't often bother modifying the OEM downpipe; sorry.
#10
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It's a '95 Import, only Imports post 96 are subject to the stricter emmissions test.
Hades; I havnt put the downpipe back on yet, as I'm waiting for heatwrap and a turbo blanket.... I'll look into modifying mine to suit the actuator
Mick; is it your job? If it is then you get paid for it so (If not then each to their own in what they do in their spare time ) I'm sure there are plenty of people in the world who appreciate your efforts IMO in this situation it's 'crap' as it's getting in the way of my lovely exhaust gases
Hades; I havnt put the downpipe back on yet, as I'm waiting for heatwrap and a turbo blanket.... I'll look into modifying mine to suit the actuator
Mick; is it your job? If it is then you get paid for it so (If not then each to their own in what they do in their spare time ) I'm sure there are plenty of people in the world who appreciate your efforts IMO in this situation it's 'crap' as it's getting in the way of my lovely exhaust gases
#11
#12
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Well if it fails I'll put in a cat once a year/ can't be arsed with that and buy a sports cat
#13
I did the same thing to my DP about 5 years ago although I cut a flap in the top bend and removed the cat etc from there! I didn't have to remove the heatshields or anything else. It made a significant difference to spool and performance.
For the centre cat I just bought a s/h STi5 centre, which gets swapped periodically
F
For the centre cat I just bought a s/h STi5 centre, which gets swapped periodically
F
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