need new bolt on cat converter? - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat


Reply
 
 
 
Thread Tools Search this Thread
Old 11-28-2014, 07:08 PM   #1
Junior Member
Posts like a Ricer Type-R
Thread Starter
 
Join Date: Nov 2014
Posts: 18
Thanked 0 Times in 0 Posts
mr roj 1 is on a distinguished road
Default need new bolt on cat converter?

I have a 99 SSEI series 2 engine. im from Indiana.
I need to replace my cat and i have to stay emission compliant. Id like a high flo bolt on type converter. i believe its 2.5 in and 2.5 out dia. I have seen different grades of converters but i am unsure on the grading system and how it relates to the emissions. I know i will need to weld one side but would prefer the other side is bolt on.
Any advice would be appreciated. Thank you!!!!
mr roj 1 is offline   Reply With Quote
Old 11-28-2014, 08:27 PM   #2
Senior Administrator


Certified Car Nut
 
Mike's Avatar
 
Join Date: Jul 2003
Location: Horseheads, NY
Posts: 15,641
Thanked 995 Times in 772 Posts
Mike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond repute
Default

In order to go "highflow" bolt on, you would have to upgrade the current pipe from 2.5 to 3". zzperformance.com and 3800performance.com have the 3" highflow cats that bolt on. Otherwise, it wouldn't be highflow.

As far as emissions goes, as long as the rear O2 sensor sees the exhaust in a different state vs what the front O2 sensor sees, you will be fine.

Now, my question is going to be, what other mods do you currently have or plan on doing to the engine?
Mike is offline   Reply With Quote
Old 11-28-2014, 08:45 PM   #3
Junior Member
Posts like a Ricer Type-R
Thread Starter
 
Join Date: Nov 2014
Posts: 18
Thanked 0 Times in 0 Posts
mr roj 1 is on a distinguished road
Default

I am installing a true cold air intake now
mr roj 1 is offline   Reply With Quote
Old 11-28-2014, 08:48 PM   #4
Senior Administrator


Certified Car Nut
 
Mike's Avatar
 
Join Date: Jul 2003
Location: Horseheads, NY
Posts: 15,641
Thanked 995 Times in 772 Posts
Mike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond repute
Default

In order to achieve maximum results from a high flow cat, one must also increase airflow through the engine. Usually a bigger cam, ported intake manifold, bigger valves and replace the restrictive exhaust manifolds with headers and a faster supercharger. Otherwise, the highflow cat is just a waste money really.
Mike is offline   Reply With Quote
Old 11-28-2014, 09:02 PM   #5
Junior Member
Posts like a Ricer Type-R
Thread Starter
 
Join Date: Nov 2014
Posts: 18
Thanked 0 Times in 0 Posts
mr roj 1 is on a distinguished road
Default

Thanks for your advice. The cat needs to replaced anyway so I just thought goin with a high flow bolt on like the from zzzz
mr roj 1 is offline   Reply With Quote
Old 11-30-2014, 01:45 AM   #6
Senior Member
True Car Nut
 
rjolly87's Avatar
 
Join Date: Jun 2003
Location: Las Cruces, NM
Posts: 6,854
Thanked 298 Times in 246 Posts
rjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant futurerjolly87 has a brilliant future
Default

What is involved with inspections in your area? Is the emissions test involving a sniffer, or something different?

The nice thing about these cars is that the cats are very straight forward, and an exhaust shop can drop a unit in blindfolded, but depending on the level of emission testing, you may need to look at a heavy metal cat, which can add up fairly quick. Sometimes the standard high flow units can be hit or miss as far as keeping emissions happy.
rjolly87 is offline   Reply With Quote
Old 11-30-2014, 02:00 AM   #7
Junior Member
Posts like a Ricer Type-R
Thread Starter
 
Join Date: Nov 2014
Posts: 18
Thanked 0 Times in 0 Posts
mr roj 1 is on a distinguished road
Default

emissions here are just plugged into the cars computer to be sure all the senors have read and completed their cycles. no sniffers for a 99 here. any thoughts?
mr roj 1 is offline   Reply With Quote
Old 11-30-2014, 09:10 AM   #8
Senior Member
True Car Nut
 
jwfirebird's Avatar
 
Join Date: Dec 2009
Location: western,ny state
Posts: 9,616
Thanked 563 Times in 481 Posts
jwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond repute
Default

you can go a few ways, you can just put a stock style one in and not worry, or you can strait pipe it and get your computer tuned to not look at that. or you can get hpt and do it yourself, this is the most expensive but if you plan on modifying your car in increments it will be necessary to tune your car at each point to account for the mod, and the tuners are likely going to want a couple hundred each time.
jwfirebird is offline   Reply With Quote
Old 11-30-2014, 09:50 AM   #9
Senior Administrator


Certified Car Nut
 
Mike's Avatar
 
Join Date: Jul 2003
Location: Horseheads, NY
Posts: 15,641
Thanked 995 Times in 772 Posts
Mike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond repute
Default

Quote:
Originally Posted by mr roj 1 View Post
emissions here are just plugged into the cars computer to be sure all the senors have read and completed their cycles. no sniffers for a 99 here. any thoughts?
You could get a O2 simulator. Its a little device that plugs in where the O2 sensor use to go and it makes the PCM think the O2 sensor is working.
Mike is offline   Reply With Quote
Old 11-30-2014, 03:48 PM   #10
Junior Member
Posts like a Ricer Type-R
Thread Starter
 
Join Date: Nov 2014
Posts: 18
Thanked 0 Times in 0 Posts
mr roj 1 is on a distinguished road
Default

Good input guys, thank you and I saw those simulators.
Now I'm running into a new ???
I can get a stainless down pipe with a hi flow cat from ZZP. In my area the stainless would be a good idea for the winters here and road salt. The rest of the exhaust is aluminized coated metal that is in great condition. I need to know about welding the stainless to the aluminized metal pipe,,,,,,,, I have read many different "theorys" on this. Any have experience doing this? Thank you
mr roj 1 is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Any recommendations on a new Cat Converter? MooseGundr 1992-1999 20 04-30-2006 01:43 PM
12-bolt "main", 12-bolt rear MikeDiaz Classics (Star Chief and 1957 to 1986) 11 04-23-2006 02:10 AM
Cat converter question. sellncars 1992-1999 4 02-02-2005 02:47 AM
Will a new Cat converter be louder ????? TelePlayer 1992-1999 7 07-29-2004 11:37 PM
Questions on Removel of CAT converter morsmortis 1992-1999 8 10-16-2003 11:34 AM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 07:34 PM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.