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Discussion Starter · #1 ·
I plan on having at least one cat on this car to prevent the soot problems I had in my ISF. I know E85 can help with smell but it is still not very widely available here in AZ. So my questions being: Is there any "better" spot to have the cats? For example would having catted DP's and a resonated mid be any better than catless DP's and a catted mid? Any pros and cons to either setup?

The only thing I can think of off hand (if my understanding is correct) is that having the catted DP's will allow the car to work with a stock map when taken in for service while not catted will throw a CEL.
 

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Catless DP then Catted mid pipe. Cats easier to replace in the mid pipe then the DP, also cats in the mid pipe will be exposed to LESS heat than if they were in the DP. Once the DP are upgraded cat or catless you will need a tune . Remember the catted DP will flow much more the OEM would and you need to adjust for that (tune).
 

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I have heard a few people mention the Catted DPs failing on them. The High Flow Cats in the DPs are exposed to far greater temps than they would be if installed firther downstream (i.e. Mid-Pipe) causing them to fail prematurely.
 

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we are working on a catted midpipe right now using some brand new RACE proven cats. They are amazing units and are designed to take whatever you can throw at them.

Eric
 

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If you were doing FTP testing, then you want the cats closest to the exhaust ports. They light off quicker. However for your normal every day smog test, in the midpipe.

The barrier to doing the DP most of the time is the labor involved.
 

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Tokyo Nightmare
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I would say midpipe.

1. Less obstructions/restriction closer to the turbine
2. You can run just a single cat on the midpipe, as opposed to two on the downpipes.
3. Ease of maintenance
 

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^ I thought about running just a single race cat in the mid-pipe but I noticed all catted midpipes always run two. Would one 200 cell race cat mitigate the soot and smell?
 

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Back in the early '90's, I used to use Random Technologies Stainless high flow cats.

http://www.randomtechnology.com/Catalytic%20Converter%20Installation%20Instructions.htm

Super High Flow Catalytic Converters
Installation Guidelines

IMPORTANT
sFor optimum performance, the converter must be installed so exhaust flows through it in the proper direction. When laying beneath the vehicle with your feet towards the rear, the converter should be installed so the numbers stamped into it are readable.
s Random Technology Super Flow catalytic converters are designed to fit a variety of vehicles. Special adapters may be required or special air tube adapters may be required.
s If a converter with air tubes is installed on a vehicle not equipped with an air management system, both air tube fittings must be plugged.
s If a converter is installed on a vehicle with an air management system, one air tube elbow & one plug must be used.​
Plug Installation
Determine which air tube fittings (if either) are to be used to make air connection in your application. (Plug the side away from the vehicle's air supply management system.) Plug the fitting(s) not used before installing converter.

1. As in Figure 1, place converter on a secure surface with air tube fittings up, being careful not to crush the converter body or heat shield.
2. Place plug(s) into airtube fitting(s). See Figure 2 for direction of plug.
3. With a hammer tap plug(s) into airtube fitting (s) until seated. The top of the plug(s) will be flush with the end(s) of the tube. See
Figure 3.
4. Crimp the end of the tube over the plug with pliers. Crimp in at least 4 places. See Figure 4.

Airtube Elbow Installation
The airtube elbow is installed on the same side of the converter as the
vehicle's air supply management system. The remaining tube should be plugged (See above). If your vehicle is not equipped with an air management system, both tubes should have been plugged.

After installing catalytic converter on the vehicle:
1. As shown in Figure 1, insert the airtube elbow into the converter's airtube fitting.
2. Position elbow in correct direction to connect air management system and secure either by welding or by using a small clamp.
3. Complete connection to the vehicle's air management system. (An airtube attachment kit may be required.)


Important Notice
To any person engaged in the business of repairing, servicing, selling, leasing or trading motor vehicles or motor vehicle engines, or who operates a fleet of motor vehicles.
Aftermarket converters may be installed in the following situations.
1. If the vehicle is missing a converter;
2. If a state or local inspection program has determined the existing converter has been lead-poisoned or damaged or otherwise needs replacement;
3. If the vehicle is more than five (5) years old or has more than 50,000 miles and a legitimate need for replacement has been established and documented. (This situation
normally would include only plugged converters or those damaged to the point where unrepairable exhaust leaks are present.)
Note: In order to establish and document that the circumstances permitting replacement of an original or missing converter with an aftermarket converter, the installer must include the customer's name, complete address, and the make, model year and mileage of the vehicle on the service invoice along with a stated reason for replacement. (Where a state or local government has determined that a converter is damaged or needs replacement, the service or repair facility also should retain a copy of the written statement or order by a proper government representative which indicates that the converter should be replaced and attach it to the invoice.)
Where the replacement need has not been verified by a proper state or local government representative, the customer and a representative of the service or repair facility must sign a statement verifying that replacement is justified
This statement form, which is supplied below, must be attached to the invoice and retained by the installer for six (6) months, and the replaced converter (if any) for at least 15 days from the date of installation.
Catalytic converters are emission control devices which are designed to last the life of the vehicle and do not normally require replacement. Furthermore, if the vehicle is properly used and maintained, original converters are covered by the emissions control warranty for five (5) years or 50,000 miles. Federal law prohibits repair businesses from replacing these devices except under certain limited circumstances.
Important
In order for the installation of an aftermarket converter not to be considered a violation of section 203(a) (3) of the Clean Air Act, the converter must also:​
1. Be installed only in situations as defined in the three situations above;
2. Be in the same location as the original converter;
3. Be the same type of converter as the original converter (i.e., oxidation, 3-way plus oxidation);
4. Be the proper converter for the vehicle application as determined and specified in the aftermarket catalytic converter application guide;
5. Be connected properly to any existing air injection components on the vehicle;
6. Be installed with all the other required converters for the particular application if more than one converter was specified in the aftermarket catalytic converter application guide;
7. Be accompanied by the warranty information card, filled in by the installer. (Warranty Card is included in converter package.)
 

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Discussion Starter · #10 ·
Now that you guys mention it I do recall some problems with cats failing due to high heat on the ISF forums so it does seem like the mid would be the best idea. Az doesn't do visual inspections or sniffer on newer cars just OBDII and gas cap tests so I'm not worried about passing smog. If it weren't for the soot I'd run catless, the smell I don't mind so much.

I read that the DP's were a little tricky to get to and some people had issues with the bolts breaking?

My mod order will probably be midpipes > cobb ap with OTS maps > catless DP's/intakes/injectors at the same time since those all require a tune which means I'd get only have to get custom tuned once instead of multiple times. I may also do the 2012 inlets at the same time to round it all out, then move on to cosmetic things like wheels/springs etc.

With those basic mods am I better off with the 3" intakes or will the 2.75" be fine? I know the 3" help with preventing the MAF from maxing out but at what point is it necessary to go with 3" over the smaller ones?
 

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Best cats are HJS and EMITEC, pricey but WRC proven.
+1

regarding the OP question I think midpipe is best place for sports hfc and catless downpipes
 

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Cobb is the only one I've seen with catted midpipe sofar. Glad to hear ams will offer one too! Considering the issues people have with these catted downpipes its probably just safer to run them in the midpipe. Would possibly allow for more horse power??
 

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Cobb is the only one I've seen with catted midpipe sofar. Glad to hear ams will offer one too! Considering the issues people have with these catted downpipes its probably just safer to run them in the midpipe. Would possibly allow for more horse power??
+1 I dunno why more manufacturers haven't jumped on this. Cobb's really the only solution right now for those who want cats.
 

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Cobb is the only one I've seen with catted midpipe sofar. Glad to hear ams will offer one too! Considering the issues people have with these catted downpipes its probably just safer to run them in the midpipe. Would possibly allow for more horse power??
I'm pretty sure AAM competition now sells a catted mid-pipe.
 

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Now that you guys mention it I do recall some problems with cats failing due to high heat on the ISF forums so it does seem like the mid would be the best idea. Az doesn't do visual inspections or sniffer on newer cars just OBDII and gas cap tests so I'm not worried about passing smog. If it weren't for the soot I'd run catless, the smell I don't mind so much.

I read that the DP's were a little tricky to get to and some people had issues with the bolts breaking?

My mod order will probably be midpipes > cobb ap with OTS maps > catless DP's/intakes/injectors at the same time since those all require a tune which means I'd get only have to get custom tuned once instead of multiple times. I may also do the 2012 inlets at the same time to round it all out, then move on to cosmetic things like wheels/springs etc.

With those basic mods am I better off with the 3" intakes or will the 2.75" be fine? I know the 3" help with preventing the MAF from maxing out but at what point is it necessary to go with 3" over the smaller ones?
I went with the Cobb 2.75 intake so I could run it without tune until that day arrives. After talking to two tuners and "cornedout..." (a member on this forum) I stuck with the 2.75 decision. He is making BIG power using the 2.75 intakes with no issues.
 

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Discussion Starter · #16 ·
Yes AAM has a catted mid now.

Socalaviator what other mods do you have? The gotboost intakes are $535 which is pretty cheap compared to even some of the 2.75 setups and it allows room for future growth. Cobb has some OTS maps for 3" intakes that can be used before a custom tune so in that case I can prob install them at the same time as I get the cobb ap then save the injectors and DP's for later.
 

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Yes AAM has a catted mid now.

Socalaviator what other mods do you have? The gotboost intakes are $535 which is pretty cheap compared to even some of the 2.75 setups and it allows room for future growth. Cobb has some OTS maps for 3" intakes that can be used before a custom tune so in that case I can prob install them at the same time as I get the cobb ap then save the injectors and DP's for later.
The Gotboost intakes are the way to go definitely. Great price, seller, builder, etc.... but you do have to install a Cobb AP and run some type of adjustment for those. I got the Cobb SF intakes used on this forum for cheap and I plan on driving it without tune for a while.
My mods are Stillen exhaust, AAM Midpipe, and Cobb intakes. Sitting in my guestroom right now is a CObb AP, ID 1000 injectors. Soon comes Titek DPs and 2012 inlet pipes.
 

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we are working on a catted midpipe right now using some brand new RACE proven cats. They are amazing units and are designed to take whatever you can throw at them.

Eric
Eric,
Are you working on a catted version of just the midpipes or are you also going to try to adapt these cats to your downpipe as well?
 

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These new cats are too big size wise to put in our downpipes so we have to put them at the entry point of the midpipe. We will more than likely be discontinuing our HFC downpipes as the new catted Mid will be a much better solution.

We are even sending one to Ryan at Forged to get one a track/street car and beat the snot out of it for a few weeks to put some real heat through it


Eric
 

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The Gotboost intakes are the way to go definitely. Great price, seller, builder, etc.... but you do have to install a Cobb AP and run some type of adjustment for those. I got the Cobb SF intakes used on this forum for cheap and I plan on driving it without tune for a while. My mods are Stillen exhaust, AAM Midpipe, and Cobb intakes. Sitting in my guestroom right now is a CObb AP, ID 1000 injectors. Soon comes Titek DPs and 2012 inlet pipes.
Are those the 90mm Titek DP's? Can you PM me the price you paid?
 
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