I got my car back on Friday from a shop that builds race cars. They installed a Mina pulley for me (lots of fun by the way). I left two high flow cats for them to install too - Magnaflow # 59975. When I went to pick up my car, the shop owner told me he didn't install the cats because of issues with the O2 sensors. I am dealing with personal issues right now and I can not recall exactly what he said as my mind is elsewhere, but I THINK he said the the high flow cats can only accommodate one O2 sensor each, but that the STR needs two per cat (presumably on before and one after the cats). He said if he installed it, I would be living with a check engine light ("CEL"). He advised me to return the cats, and not to even go to another shop for install because I would regret it. He advised I get a good cat back system and dump the resonators for performance. Again, this shop builds race cars and I think the reason the owner even opened the shop was to fund his car racing additction, so I am skeptical to take what he says with a grain of salt but I doubt he sees many STRs so...

Now I know many members here run these very specific high flow cats. I plan on taking it to another shop for a second opinion anyway. Is there anything you guys with these cats can tell me in preparations to discuss potential issues with O2 sensors and these cats for the next shop I take it too?

 

I installed these cats in order to fix my cat related check engine light code, the code has stayed off now many miles later with no problems. The O2 bungs should be welded in a specific spot due to the exhaust flow but I can't give you any more info than that.

 

No problems for me, other than the cats my exhaust is 100% OEM and no CELs...

End whatever relationship you have with this shop, you may regret it otherwise...lol...I fear this shop will ensure you get a CEL if you let them do it...It's total BS when any shop says you'll regret going to another shop...

 

^^ +1

By all accounts, installing a pulley is no picnic in the park, but should not be something that causes a fully equipped shop to do any belly aching.

 

Have the 59975's myself and I was a little doubtful before installing them myself. The exhaust shop that did mine only does exhausts and they did a great job. They need to weld an O2 bung for the sensors before and after each of the cats. If its done properly there should be no CEL issues. I've been driving mine for months now and they work great.

I suggest you go to a shop that only does exhaust work, they'll know how to do it.

 

Thanks guys I will take this advice to my second opinion shop.

 

Ditto to all with Magnaflow or any other hi-flow cats. I run them, and as previously mentioned, will repeat: Weld O2 sensor bungs approx. 2" fro and aft of cats.

 

Yep, my daughters had 2 bad cats, put on the magnaflow by adding a bung to the front of the cat and one downstream about 6". No problems for over a year now. Had to go to 3 different shops though. The other 2 said it would not work that the magnaflow were "pre OBDII"...... idiots.

Also it made that 4.0 sound downright mean, even with the stock components the rest of the way.

 

Good info as I see these in my future, how much labor is it to install the 02 bung things? I want to know what kind of bill I am looking at. Also, anyone do the X Pipe install at same time? I want a little more aggressive but no droning noise! thanks

 

BMW745, The cats and install are straight forward and relatively inexpensive (plus she'll breath like a dragon). Cats and x-pipe install is between $200-$300 labor.

 

I have these cats as well, but the shop I used had issues installing them. It appears my experience is an outlier, but make sure you have someone who knows what they are doing, do it correctly otherwise your car will throw codes and make you sad. They placed the O2's as close as possible to the cats so they heat up correctly on start up. I dont notice any performance gain because it started getting hot in AZ and I dont floor my car much. Methinks it shifted the power curve up and higher though.

As for the center resonator, dont buy the 11378 because it sounds like crap kinda, lol, not very refined. Instead buy the 14385 or the 11385. Some members have this setup and could possibly share a video?

Use Google's shop function for the best deal.

There is a whole thread dedicated to this with videos of my car, search for it, it wasn't long ago. Best of luck and share your results.

 

I have no idea how you guys are so lucky but today I got my car back from a notable performance shop (they were modding Lambos, Porsches, turbo M3s, Skylines, turbo Lexus', GT-Rs, etc) and they race cars and sure enough, 20 minutes after I got my car back from their hi flow cats and resoanted x-pipe install, good ol' check engine light came on. They are in a different city and I had to rent a car to get them to work on my car and I just dont have time to go back I don't know what to do. I', very busy its going to be a while before I can do anything about, I wanted to dyno the car ASAP but I'm not going to right away with the CEL on. Do you guys know if Jaguars run rich when CEL on like Mercedes does? This will effect performnce.

 

OBD tool can tell you fuel trims but first use it to check it's running CL (closed loop) as otherwise it'll be rich for sure. (This stuff is called "live data" so check any tool has that.)

 

Thanks JagV8, given the number of times my CEL has activited, I think I am going to have to get an OBD tool. Only Jag owners probably need these lol.

Assuming the CEL is O2 sensor related in respect to the high flow cats, do you guys think this CEL eliminator will work (please see link below titled "Weapon R")....

Weapon-R

 

You could have an exhaut leak or they could have wrongly connected an O2 or ... well, don't plan on bypassing something (perhaps with dire results) till you at least know the codes! And fuel trims, and etc.

By law all cars have OBD so they all have these sorts of issues in one form or another, especially if not kept OE. Not the end of the world - the tools are quite cheap.

 

I had an exhaust shop tell me they would not install the 59975s as they were for OBDI cars and Colorado is getting stricter and stricter (not quite California, but close) with their emissions laws. I ended up with the Magnaflow 99675HM which is very similar except designed for OBDII cars.

 

There's a lot of ignorance. So long as a cat does what is needed there's no such thing as for OBD1 or OBD2.

 

The problem is regulations. If it doesn't have the blessing of the state agency then it can be a very big deal if an installer is caught using them. If your state has a rigorous inspection program and the car is of a certain age or newer then they can nail you. California is **** like in this respect. Cars there built after 1976 must have all of their original pollution control systems intact, no modifications allowed. That's really hard for a lot of cars 1977 and newer.

 

I thought Cal was the only place so bad. Are others?

You'd expect that the only important thing would be that the cat was effective, i.e. dealt with specific emissions, but lawmakers seem to lose sight of reality sometimes....

 

What's needed is someone with the hi-flows to have an emission inspection and compare the results to what the Calif standards are.
All emission tests I've had done were tail pipe only with no visual of components.
I'm only stating the above to prove that the hi flows would pass any emission test in Calif., NOT saying anyone should do it.
A previous car I had....'86 Olds 442 had a "forbidden" 350 Olds motor in it (307 was standard) and I had hi flow cats on it...all of that stuff passed.
How many places are going to look for the components anyway.
Disclaimer.....I'm not advocating anyone do something illegal..