100cel -> 200+cell & Power Output/Fumes

[Ravskie]

Hello all - odd question.

I knew that upgrading to a 3" TBE with a 100cell cat would increase power and noise but after a few months of running it I am now getting just a tad sick from the fumes being emitted. I am wondering if anyone here has an RB25DET running a 3" Exhaust with a 200cel cat or higher and can confirm what power they are able to get from running a higher cel cat and how bad the fumes are,  better if you have changed from a 100cell cat to a higher cell cat. 

Currently making 204rwkw with no power modifications besides the Nistune & TBE - I am willing to sacrifice power.

 

I appreciate any feedback ?

[KiwiRS4T]

Are you sure that the fumes are attributable to the 100 cell cat? Are your breathers and PCV valve up to scratch? Have you compression tested to see if you might have excessive blow by? Do you know someone with the ability to put an exhaust gas analyzer on you tail pipe? Are you running the stock blow off valve?

[tridentt150v]

Get a tune!!!  Heaps of us here with performance CAT's and no fumes, and way more power than 200rwkw.

And when you are talking fumes, is it oil, gearbox oil, oil splash fumes, unburnt fuel, burnt fuel, burnt coolant, can you see smoke? is there black all over the back of the car? does the car leak oil when parked? heaps of problems that can be easily fixed, need to be more specific sorry.  

[V28VX37]

What fuel are you using?

I'm finding that going from 98 to E85 has made the car slightly more fume-y, using the exact same exhaust system and 100-cell cat.
I reckon ethanol in general provides a more olfactory experience.

[Ravskie]

Thank you both for your responses!

@KiwiRS4T

I have not checked any of what you have said - I will make a note and see if I come up with anything. I am not running any aftermarket BOV.

 

@tridentt150v

I have a Nistune ECU which was installed and mapped by a performance workshop already. I know the coolant and oil smell so I can write that off. No smoke and the back of the car is clean. My old STI ran rich but the smell is different to what I am getting now - I'm starting to think I may have a leak somewhere - the exhaust is new and was installed by a workshop.

[Ravskie]

@V28VX37 Always running 98RON mate, I haven't reached the E85 post yet hahaha!

[tridentt150v]

Check the filler neck.....if its raw fuel then it can be an issue.  When they comply the car in Australia they replace the filler neck with a small hole 'unleaded' one.  Dodgy shops don't bond this to the original filler pipe/hose....a few of us on here have had to Sikaflex the gap.

[Ravskie]

Will check that out mate, thank you!

[vxsr33]

Did you only notice the fumes after the exhaust and cat install?
I went from a 3 inch highflow cat (unknown what brand, maybe xforce?) to a venom 100cell and the fumes were definitely worse, but mainly when the car is idling in the garage is the only time i can really notice it. I'm assuming a 100cell cat won't do much in terms of reducing nasty emissions. I would just keep the 100 cell cat if i were you, changing cats could also put the tune out of whack.
How bad are the fumes? It shouldn't really be noticable at all with normal driving, unless you are moving really slowly in traffic or stationary.

[Ravskie]

@vxsr33 Yeah noticeable with the change in exhaust - I mean I guess over time I have just gotten sick of smelling it on idle/startup/traffic lights etc

[32psi]

I went from a xforce 100cell cat to an Outlaw 200cell cat and the difference in fume smell was huge. Tune wasn't altered at all, I was pretty pissed about the Outlaw because it wasn't cheap but well worth it when I warm it up in the garage. 440rwkw goes through it.

[MrStabby]

Agree. Went from 200 to 100 cell and fumes noticeably worse. May eventually go back to 200 cell.