downstream second cat removal
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downstream second cat removal
I have read the upstream 2-into-1 catalytic converters should be kept what about the second downstream catalytic converter any better benefits from removing it?
Re: downstream second cat removal
Hi,
Depends on your mods. I recently removed mine as part of a 3" exhaust upgrade and my dyno #'s definitely went up. But I'm also running a bigger turbo/injectors/more boost.
TD
Depends on your mods. I recently removed mine as part of a 3" exhaust upgrade and my dyno #'s definitely went up. But I'm also running a bigger turbo/injectors/more boost.
TD
Turbo Subies:
'87 GL-10 Turbo - SOLD
'90 BJ EJ22T/DOHC & 5speed swap - SOLD
'04 FXT, Forged internals, VF39, STI TMIC, Cobb AP- SOLD
'93 Legacy SS - 5-speed, SOLD :-(
'02 WRX -SOLD
'96 BD-turbo'd-SOLD
'98 SF - NA-T
'87 GL-10 Turbo - SOLD
'90 BJ EJ22T/DOHC & 5speed swap - SOLD
'04 FXT, Forged internals, VF39, STI TMIC, Cobb AP- SOLD
'93 Legacy SS - 5-speed, SOLD :-(
'02 WRX -SOLD
'96 BD-turbo'd-SOLD
'98 SF - NA-T
Re: downstream second cat removal
I removed mine also when installed stainless headers.
Charles
90' White/Gray Outback DD workhorse (670,xxx) miles
92' Onyx Metallic (430,xxx) Wife's DD
68' Barracuda formula S 340 4spd coupe (ongoing project)
66' Mustang 2+2 4spd wife's (ongoing project)
90' White/Gray Outback DD workhorse (670,xxx) miles
92' Onyx Metallic (430,xxx) Wife's DD
68' Barracuda formula S 340 4spd coupe (ongoing project)
66' Mustang 2+2 4spd wife's (ongoing project)
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- Fifth Gear
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Re: downstream second cat removal
haven't had a cat since 2006
91 L-TW Wagon with a full Swap -RIP
92 SS Prefaced, GD dash swapped, 22T/205 Hybrid 20 psi - BEAST!
93 SS Bone Stock Gone!
94 TW Bone Stock Gone!
91 SS 4EAT Sold!
98 LGT 4EAT
98 LGT Wagon 4EAT
92 SS Prefaced, GD dash swapped, 22T/205 Hybrid 20 psi - BEAST!
93 SS Bone Stock Gone!
94 TW Bone Stock Gone!
91 SS 4EAT Sold!
98 LGT 4EAT
98 LGT Wagon 4EAT
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Re: downstream second cat removal
I don't think removing the second cat on a stock engine setup will make a huge difference in the scheme of things, but if you have more upgrades planned for later I don't think it could hurt.
1992 Legacy SS 5mt, build in progress
Josh Colombo wrote: ↑Mon Jan 14, 2002 10:23 am Wait....I'm confused now.
Re: downstream second cat removal
When the 2nd cat is removed, what happens to the oxygen sensor? Just take it off?
Re: downstream second cat removal
There is no O2 sensor in the second cat on the first GEN legacies just up by the turbo.
Td
Td
Turbo Subies:
'87 GL-10 Turbo - SOLD
'90 BJ EJ22T/DOHC & 5speed swap - SOLD
'04 FXT, Forged internals, VF39, STI TMIC, Cobb AP- SOLD
'93 Legacy SS - 5-speed, SOLD :-(
'02 WRX -SOLD
'96 BD-turbo'd-SOLD
'98 SF - NA-T
'87 GL-10 Turbo - SOLD
'90 BJ EJ22T/DOHC & 5speed swap - SOLD
'04 FXT, Forged internals, VF39, STI TMIC, Cobb AP- SOLD
'93 Legacy SS - 5-speed, SOLD :-(
'02 WRX -SOLD
'96 BD-turbo'd-SOLD
'98 SF - NA-T
Re: downstream second cat removal
Does anyone know what the size and thread pitch is for the factory o2 sensor? I need to add a bung at the stock location on my newly purchased Invidia Bellmouth Catless DP.
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- Fifth Gear
- Posts: 6322
- Joined: Fri Jun 20, 2008 8:17 am
- Location: Lakewood, Wa 98439
- Contact:
Re: downstream second cat removal
They're mostly the same. Any exhaust shop will have them for around 10 bucks.
91 L-TW Wagon with a full Swap -RIP
92 SS Prefaced, GD dash swapped, 22T/205 Hybrid 20 psi - BEAST!
93 SS Bone Stock Gone!
94 TW Bone Stock Gone!
91 SS 4EAT Sold!
98 LGT 4EAT
98 LGT Wagon 4EAT
92 SS Prefaced, GD dash swapped, 22T/205 Hybrid 20 psi - BEAST!
93 SS Bone Stock Gone!
94 TW Bone Stock Gone!
91 SS 4EAT Sold!
98 LGT 4EAT
98 LGT Wagon 4EAT
Re: downstream second cat removal
Got it thanks. It appears that the standard size is M18x1.5.