2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

Calling all exhaust gurus...

Thread Tools
 
Search this Thread
 
Old Nov 20, 2006 | 09:57 AM
  #1  
schmol's Avatar
Thread Starter
Wanna play with my Wankel
Tenured Member 05 Years
 
Joined: Oct 2006
Posts: 378
Likes: 0
From: york PA
Calling all exhaust gurus...

Alright here's what I got, just picked up a '89 vert that has a custom exhaust on it already. He had a complete system installed with only one Cat which after about 2 weeks of driving, the Cat had a hole burnt into it.

Now from what I've been reading on this site, you have to be somewhat careful on what you do with the Cats on these cars. My question is, what Cats can you eliminate without effecting the 5th & 6th ports, which I'm assuming is the main Cat. If I buy a new down pipe, I also assuming that eliminates the PreCat, right? Now what about the Main, can I get a less restrictive Main Cat as long as it has the split air pipe on it?

Can you give me some hints at what would be a good combination of downpipe and cats? It would be greatly appreciated...Yes I used the search feature, but everyone was lkinda everywhere on this subject. TIA
Reply
Old Nov 20, 2006 | 10:00 AM
  #2  
Mx6-Rx7 Addict's Avatar
Brap Brap Brap
Tenured Member 05 Years
 
Joined: Oct 2002
Posts: 678
Likes: 0
From: Corpus Christi, TX
Series 5 NA's 5th and 6th ports are actuated by the air pump. Put a full downpipe/presilencer/midpipe and be happy.

Racing beat is a good maker.

Justin
Reply
Old Nov 20, 2006 | 10:01 AM
  #3  
schmol's Avatar
Thread Starter
Wanna play with my Wankel
Tenured Member 05 Years
 
Joined: Oct 2006
Posts: 378
Likes: 0
From: york PA
So you are saying I can safely remove the stock main cat and replace it with a less restirctive Cat without the split air pipe or just get rid of it altogether?
Reply
Old Nov 20, 2006 | 10:03 AM
  #4  
Mx6-Rx7 Addict's Avatar
Brap Brap Brap
Tenured Member 05 Years
 
Joined: Oct 2002
Posts: 678
Likes: 0
From: Corpus Christi, TX
Yes, you will not have a problem with eliminating the cats besides emissions.
Reply
Old Nov 20, 2006 | 10:05 AM
  #5  
schmol's Avatar
Thread Starter
Wanna play with my Wankel
Tenured Member 05 Years
 
Joined: Oct 2006
Posts: 378
Likes: 0
From: york PA
Pre '95 cars only have a visual on emissions here in PA, so I guess I shold still have one there for it to pass, just make it a really free flowing Cat.
Reply
Old Nov 20, 2006 | 10:07 AM
  #6  
schmol's Avatar
Thread Starter
Wanna play with my Wankel
Tenured Member 05 Years
 
Joined: Oct 2006
Posts: 378
Likes: 0
From: york PA
Any good Fuel pressure regulator manufacturers that you would suggest or just replace it with the factory version? I'm only asking this because that is what the previous owner said it needed, said it was going bad and it made the car run leaner than normal and burnt out the Cat.
Reply
Old Nov 20, 2006 | 10:07 AM
  #7  
Mx6-Rx7 Addict's Avatar
Brap Brap Brap
Tenured Member 05 Years
 
Joined: Oct 2002
Posts: 678
Likes: 0
From: Corpus Christi, TX
Or just gut it

I've only been to one place who actually looked under the car. They saw i had no cat and wouldn't pass me. I drove to the place right next door and they passed me and were trying to buy my car.

You could go with a racing beat downpipe or bonez downpipe + midpipe and it will eliminate the precats and the main cat. A much noticed power gain will be expected also.

Justin
Reply
Old Nov 20, 2006 | 10:10 AM
  #8  
Mx6-Rx7 Addict's Avatar
Brap Brap Brap
Tenured Member 05 Years
 
Joined: Oct 2002
Posts: 678
Likes: 0
From: Corpus Christi, TX
I don't think the fuel pressure regulator would have much to do with your car running too lean, unless it's completely shot. How many miles are on it? Typically from what i've experience, clogging a cat is due to the vehicle running too rich, usually caused by a faulty o2 sensor or other sensors to cause the car to run richer.
Reply
Old Nov 20, 2006 | 10:12 AM
  #9  
riverzendz's Avatar
Interruptor Illuminada
Tenured Member 10 Years
 
Joined: Apr 2006
Posts: 1,504
Likes: 0
From: MD
Originally Posted by schmol
So you are saying I can safely remove the stock main cat and replace it with a less restirctive Cat without the split air pipe or just get rid of it altogether?

I'm from York, PA too. How's it going man. From past inspection experience with my RX-7 in York, if it looks like a cat it is a cat and will pass. I passed my visual inspection everytime with the RB pre-silencer. No questions asked.

Take it to Angels Cycle World. He'll take care of ya.
Reply
Old Nov 20, 2006 | 10:19 AM
  #10  
schmol's Avatar
Thread Starter
Wanna play with my Wankel
Tenured Member 05 Years
 
Joined: Oct 2006
Posts: 378
Likes: 0
From: york PA
Cool, I think I'll still put a cat on it, but it will be much lighter than when I bought it. That's just for the occasional inspecter that looks under the car.

Riv, it's good to see someone so close on the boards. Once I get this vert on the road, we'll have to meet up and you could give me some pointer on what to do with her. As for Angel's, I totally forgot all about that place, Hell I even bought a Kawi motorcycle motor from him not too long ago.
Reply
Old Nov 20, 2006 | 11:58 AM
  #11  
riverzendz's Avatar
Interruptor Illuminada
Tenured Member 10 Years
 
Joined: Apr 2006
Posts: 1,504
Likes: 0
From: MD
Angel's is great. He's a good guy too. He used to have a sweet RX-3 drag car. The rotary Suzuki bike is always fun to look at too.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Th0m4s
Build Threads
25
Feb 26, 2019 02:04 AM
thecody59
1st Generation Specific (1979-1985)
40
Aug 23, 2015 06:41 PM




All times are GMT -5. The time now is 09:52 PM.