My point Jim, is that you have r-tune cams and plenum and intake. Isn't it possible that these mods, that affect air fuel mixture DIRECTLY, are more likely to be the cause of your lean running condition?

If you can prove that the the cats were the straw that broke the camel's back then fine... they lean the mixture a little bit. I just think that the title to these threads is really misleading.

 

I had A/F done before and after install of cats. And I'm running leaner over 4K after the cats were installed.

 

a LOT leaner???

...you have a lot of mods too, right jason? I mean... I don't have a problem believing that cats will lean the mixture, I just don't see it being that significant.

PS- Thanks for the posts guys, I know I'm a little short with my responses. I'm just trying to learn as much about this as possible.

 

I'm not trying to cause panic-

im just curious if those ppl with RT cats (or test pipes for that matter) just check the plugs to see whats going on..

thats all..

 

My car is probably a good test... I ONLY have RT Cats, all else is stock.

The car pulls pretty darn good with the RT cats.

Unfortunately the car is under a foot of snow right now. It should be cleared up by the weekend. I'll pull a plug as soon as I can, It's also been 40 deg since I installed them.

 

So far the cars I know of who I I have followed on their Mod progress have the cams or plenum or both.

I have stock cams and stock plenum and my EGT reads exactly the same as it did b4 the RT Cat install.

I will check my plugs when I get a day off but I too don't see just the cats causing that much difference.

I have a blower though, we need that guy with *just* the Cats, that will be the true test.

Wouldn't my exhust tempurature rise if I was lean? It still stays between 0 and 600 and an average of 300-400 and 600 at WOT with 800 being my warning setting I have never hit once?

 

Hard to say by measuring after the cat like you are. The cat heats the exhaust temp also to extreme heat. It seems like this would cover a lean condition up. No?

 

According to this page here, there's nothing wrong with those plugs.

 

Ditto!


Here is a pic of one of my plugs. I put 18K on these with an Injen CAI and exhaust. Sorry for the pic quality, I need Santa to bring me a new digital camera.

 

apic

 

xdg

 

My measurment is *before* the cats not after. I have a bung pre cat in the RT Pipe just after the header collector.

I also just talked to someone with the Crawford Cats who was at TS and wasn't Lean either???

Regardless I have a larger fuel pump on the way to run my larger injectors and then will Dyno. I honestly don't think I am lean though, but I could be wrong. If my EGT is good for anything, then I am not lean. I had already flashed to 11.5 at TS. My question is has anyone flashed (like me) added the Cats and still been lean? Like Jeff/Jason said too, why just the RT's? The Crawford's don't go lean.

 

I've had the flash for like 6 months and was fine. Added the RT cats about 6 weeks ago and I'm now 13.9 to 14.5 across the band (14.3 @ 6000). I'm getting reflashed on Friday so I'll let you know how it turns out.
Before cats:
Stock air box (w/ K&N)
US Pulleys
Borla Headers
Injen Dual

Nothing installed after cats.

Before cats I was between 13.5 and 12.2 (12.5 @ 6000)

 

Here are some graphs of A/F on my car before and after the RT cat install-

Before:


After:


Before and after together:

 

So, if you had your ECU re-flashed and mapped exclusively for a specific set-up, how can you possibly not expect the parameters to change once you add another component?

Does anyone with a stock ECU, stock airbox and just RT Cats have any input to add to this thread regarding lean conditions?

 

The ECU was one of the first mods I did. I was a beta tester for TS so the flash was not specifically mapped for my mods, it was a generic flash. After the flash I added headers, pulleys and exhaust and the A/F was fine (see above).

 

I have test pipes w/ Borla and K&N filter, rest stock. Pulled a plug and it looks just like Chebosto's. Is Chebosto's plug showing a lean A/F?

 

The white on the ceramic is showing a lean condition yes. Look at the ceramic part not the metal.
It is not Cheston's personal plug.

AnywayZ's is there any update on this with the stock setup RT cat only who was in snow?

Thanks. I am not ruling out a reflash but I wanna do a few other things first then roadtrick (ugh)

 

Well I just glanced at my dyno charts. @ 6600 rpm my A/F is right around 12.6 and this is consistent across dyno runs. From 3k - 6.6k rpm's it stays around 13.5 gradually dropping. I'm running no cats w/ nismo headers & borla TD; so a very open exhaust. I havent bothered w/ a reflash or anything like that either.

 

Not exactly sure why this is only the RT cats either. Test pipes and Crawford high flow cats don't seem to produce the same results? I had my ECU reflashed this weekend and the A/F has been corrected (no more pinging and plugs look much better). Tadashi has some theories about the RT cats but he needs to do more testing and research. If you are running the TS ECU and have RT cats I would strongly suggest you get your A/F measured, you may need a reflash.