Random Tech VS hollowed cat
Team Owner
Joined: Sep 2001
Posts: 62,145
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From: Athens AL
C7 of the Year - Unmodified Finalist 2021
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Re: Random Tech VS hollowed cat (Tim89)
One thats hollow of course. Especially if you have a straight pipe put inside.
Might get resonance that way.
Might get resonance that way.
Thread Starter
Racer
Joined: Aug 2001
Posts: 416
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From: Astoria OR
Re: Random Tech VS hollowed cat (vader86)
The hollowed one doesn't have a pipe. I'm running two non-name brand mufflers and headers. Wasn't sure if I needed Random Tech for back pressure or something.
Team Owner
Joined: Sep 2001
Posts: 62,145
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From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Re: Random Tech VS hollowed cat (Tim89)
You dont need backpressure, it just means that you might need a heated O2 sensor if you dont use a real cat.
Team Owner
Joined: Sep 2001
Posts: 62,145
Likes: 1,730
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Re: Random Tech VS hollowed cat (Tim89)
The O2 sensor monitors the exhaust, if you lose heat in the exhaust from not having a cat, it might make the computer richen things up too much. So you might need to replace it with a heated sensor. It corrects the readings.
Thread Starter
Racer
Joined: Aug 2001
Posts: 416
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From: Astoria OR
Re: Random Tech VS hollowed cat (vader86)
How can I tell if I need to go with a heated one, will my service engine light come on to let me know? Also where do I buy a heated one, are common to buy from a company from summit? Thanks for the help.
Le Mans Master
Joined: Jan 2002
Posts: 5,320
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From: Kyle TX (Because Mojo Made me fill it in)
Re: Random Tech VS hollowed cat (Tim89)
I really doubt you will have a problem with your O2 sensor. My CAT is hollowed out and Im running LT headers on a factory O2 sensor (non heated). Havent had any problems. If you do need a heated O2 sensor, you can get them just about anywhere so I wouldnt worry. I dont have a part number, but if it comes to that, there are a few on here that has gone with heated sensors so they should be able to help.
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Thread Starter
Racer
Joined: Aug 2001
Posts: 416
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From: Astoria OR
Re: Random Tech VS hollowed cat (VetteNoob)
Ok I'll try it and see. If my car goes "lumpy when cold" I'll know what to look at first. The headers only have one sensor, is that normal or should there be two? Also after doing a search some people made a new hole for the heated ones. Can't I just use the hole thats there and put a heated one in instead of the regular one?
Le Mans Master
Joined: Jan 2002
Posts: 5,320
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From: Kyle TX (Because Mojo Made me fill it in)
Re: Random Tech VS hollowed cat (Tim89)
I believe our cars only had 1 O2 sensor and you can use the hole provided by the headers. Some people relocated the O2 bung to the collector to get a reading of all cylinders on that side instead of only 1 cylinder (Hooker Headers). So that may just depend on the headers you have. My guess is that if you need a heated O2 Sensor, the SES light will come on, mine hasnt so Im not 100% sure what will happen.
[Modified by VetteNoob, 10:38 AM 2/22/2003]
[Modified by VetteNoob, 10:38 AM 2/22/2003]
Pro
Joined: May 2000
Posts: 741
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From: Etowah, Tennessee
Re: Random Tech VS hollowed cat (Tim89)
Tim, You shouldn't have a problem at all. I have been running with both pre-cats removed, and the main cat removed also, with two Targa style mufflers on my '91 for over two years now, no problems or no codes whatsoever...Just GREAT sound!!!Good Luck! :chevy
Race Director
Joined: Aug 2002
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From: tucson AZ
St. Jude Donor '04 & '05
Re: Random Tech VS hollowed cat (Tim89)
Stay Smog legal....and go for the Random Cat.,
Will save you in the long run, while still giving you a performance increase....
tony
:smash: :smash:
Will save you in the long run, while still giving you a performance increase....
tony
:smash: :smash:
Elite Torch Red Member
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From: Exit 89 GSP,Lakewood,NJ The Land Of Mojo
Cental/South NJ Events Coordinator
CI 1-2-3-4-5-6-7-8-9-10-11-12 Vet
CI-II Burnout & Drag Champ
St. Jude Donor '03-'04-'05-'06-'07
Re: Random Tech VS hollowed cat (oldace84)
Stay Smog legal....and go for the Random Cat.,
Will save you in the long run, while still giving you a performance increase....
tony
:smash: :smash:
Will save you in the long run, while still giving you a performance increase....
tony
:smash: :smash:
Burning Brakes
Joined: Feb 2000
Posts: 1,247
Likes: 2
From: Parker, Colorado, USofA
Re: Random Tech VS hollowed cat (oldace84)
Can anybody comment on other brands? The Random Tech is $200-ish and I seem to recall another popular cat for $100-ish. I currently have headers, an offroad pipe and resonator tips hanging behind my 383 and will need a whole new system behind the headers. I've got the rear 'y' with crossover tube, and am leaning towards Flowmaster 70's for mufflers, but am undecided on the cat at the moment.
Drifting
Joined: Nov 2000
Posts: 1,276
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From: Ft. Worth Texas
St. Jude Donor '11
Re: Random Tech VS hollowed cat (RocketSled)
Can anybody comment on other brands? The Random Tech is $200-ish and I seem to recall another popular cat for $100-ish. I currently have headers, an offroad pipe and resonator tips hanging behind my 383 and will need a whole new system behind the headers. I've got the rear 'y' with crossover tube, and am leaning towards Flowmaster 70's for mufflers, but am undecided on the cat at the moment.
jeff
Team Owner
Joined: Dec 2000
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From: SE NY
Cruise-In II Veteran
Re: Random Tech VS hollowed cat (Tim89)
A few years ago a guy in FL made back to back passes with dual RT bullet cats and with straight pipes bolted in. In both cases the passes were in the 12.0x sec range.
If your O2 sensor isn't heating enough your ECM will not go closed loop or will drop out of closed loop. To check out yours see "How to Use - L98 Field Service Mode" on my site.
If your O2 sensor isn't heating enough your ECM will not go closed loop or will drop out of closed loop. To check out yours see "How to Use - L98 Field Service Mode" on my site.
