Should I remove cat?
Team Owner
Joined: Apr 2001
Posts: 22,267
Likes: 3
From: Dallas TX
Re: Should I remove cat? (dan-t)
It will be louder, and the performance gain is usually worth it in most cases along with some longtube headers. Not sure on codes, but you will need O2 eliminators. I would definitely be doing it to mine if I could get away without cats. I would go in for inspection and they would immediately fine me I'm sure.. :(
[Modified by Glock'94, 2:03 AM 12/11/2001]
[Modified by Glock'94, 2:03 AM 12/11/2001]
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: Should I remove cat? (dan-t)
As you free up flow in the exhaust system and match fuel at WOT HP will go up. To be safe you could upgrade to a hi-flow cat likt Random Technology. You will of course realize the most gain by a complete exhaust system upgrade.
Le Mans Master
Joined: Dec 1999
Posts: 8,540
Likes: 1
From: And on the fifth day, subpoenas were served to Obama senior staff
Re: Should I remove cat? (dan-t)
Don't think you need to use O2 simulators on a 94.
O2 sensor is used to measure exhaust gases for Oxygen. ECM uses this information to adjust mixture. In OBDII applications (96 and newer) O2 sensors were also placed after the cat(s) as a way for the ECM to determine if the cat was working, and set a code if it does not.
A 94 may or may not have an O2 sensor after the cat, but it is there pretty much for kicks and chuckles and should not turn on the SES light if the cat is goen. 94 was a late version OBDI system with some OBDII "experimentation and implimentation."
If the cat(s) are bad removing / replacing them could make a big difference. Removal of a good cat will provide some improvement but won't knock your socks off.
I drive through Salida once in a while. If I had my Corvette in the area, I would look to power adders such as a supercharger or turbo to make up for the altitude. I'm not a big fan of forced induction, but having been where you are, I KNOW it would be a night and day difference for you! You have some great Corvette roads, now need to get some HP back from that altitude!!!! :D
O2 sensor is used to measure exhaust gases for Oxygen. ECM uses this information to adjust mixture. In OBDII applications (96 and newer) O2 sensors were also placed after the cat(s) as a way for the ECM to determine if the cat was working, and set a code if it does not.
A 94 may or may not have an O2 sensor after the cat, but it is there pretty much for kicks and chuckles and should not turn on the SES light if the cat is goen. 94 was a late version OBDI system with some OBDII "experimentation and implimentation."
If the cat(s) are bad removing / replacing them could make a big difference. Removal of a good cat will provide some improvement but won't knock your socks off.
I drive through Salida once in a while. If I had my Corvette in the area, I would look to power adders such as a supercharger or turbo to make up for the altitude. I'm not a big fan of forced induction, but having been where you are, I KNOW it would be a night and day difference for you! You have some great Corvette roads, now need to get some HP back from that altitude!!!! :D
Melting Slicks
Joined: Jan 2000
Posts: 2,543
Likes: 0
From: Dollars Taxes
Re: Should I remove cat? (Glock'94)
Lets see, take them off and you will get:
1) Better sound
2) More HP
3) Less low end torque, more top end power (better for "not" spinning the tires...)
4) Better fuel economy
And, if your car is properly tuned, you don't need cats!! It's really only for those who "don't" take care of a car, that needs them... And most people don't, so the government made ALL cars have them... My properly tuned 1995 Lincoln Mark VIII with 90,000 miles put out 6 hydrocarbons, and that was WITHOUT the cats!!!
So, I say it's the best thing to do, but that's just me..... ;)
1) Better sound
2) More HP
3) Less low end torque, more top end power (better for "not" spinning the tires...)
4) Better fuel economy
And, if your car is properly tuned, you don't need cats!! It's really only for those who "don't" take care of a car, that needs them... And most people don't, so the government made ALL cars have them... My properly tuned 1995 Lincoln Mark VIII with 90,000 miles put out 6 hydrocarbons, and that was WITHOUT the cats!!!
So, I say it's the best thing to do, but that's just me..... ;)
Le Mans Master
Joined: Dec 1999
Posts: 8,540
Likes: 1
From: And on the fifth day, subpoenas were served to Obama senior staff
Re: Should I remove cat? (Glock'94)
Glock'94, do you know if the O2's before the cats are HO2S? If not changing to HO2S could keep the ECM/PCM in closed loop longer with cats removed or performance exhaust.
Don't think that one after the cat needs to be dealt with at all. Bet if you remove it nothing happens. On 96 it would set a code for sure, and there would be a second on the second cat.
Don't think that one after the cat needs to be dealt with at all. Bet if you remove it nothing happens. On 96 it would set a code for sure, and there would be a second on the second cat.
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Drifting
Joined: Nov 2001
Posts: 1,587
Likes: 0
From: Omaha NE
Re: Should I remove cat? (Glock'94)
The '94 does have 3 O2's. One after one of the cats, and two before. The one after the cat doesn't even send any info to the computer, so removing it won't throw a code.
Le Mans Master
Joined: Dec 1999
Posts: 8,540
Likes: 1
From: And on the fifth day, subpoenas were served to Obama senior staff
Re: Should I remove cat? (Glock'94)
Actually, ECM does monitor the O2 after the cat. It will store a code and I believe you can get reading with a scanner.
This was an early implimentation of an OBDII ability sort of like a beta test.
This was an early implimentation of an OBDII ability sort of like a beta test.
Thread Starter
Racer
Joined: Nov 2001
Posts: 370
Likes: 0
From: st.louis missouri
Re: Should I remove cat? (PeteL)
sounds like I won't have any problems with removal then,thanks Yes at 7500 ft. altitude I need all the help i can get.can't afford blower or turbo cause of payments on the vette and 3000gt vr4 are taking alll my money,the vr4 is not affected by altitude near as much as the vette thank god,the vette is running 14.7-15.0 on g-tech here, in st.louis visiting folks it ran 13.4-13.7,going there is like adding a blower then coming home like inserting a v-6 bummer.the mountains make it worth it though..thanks again for all the posts....
Thread Starter
Racer
Joined: Nov 2001
Posts: 370
Likes: 0
From: st.louis missouri
Re: Should I remove cat? (Glock'94)
yes worst part is the turbos that are slower than vette down low may hang with u up here ,had that problem with the 98 ta that i traded for the vette ,no races in vette yet accept against my vr4.
