Hi guys,

Hope this post would be informative to folks who want stock cats and a more aggressive tune.

I ordered sharkwerk exhaust that will go on the car this weekend. I am also planning on getting the giac stage 2 tune. Given that the sw exhaust uses stock cats, I wasn't sure if the stage 2 tune would work effectively.

Spoke with Tom from champion and gmp where I ordered the parts feedback summarized below:

Tom - the performance might be inconsistent but there will be a gain. When the cats get too hot, ecu will dial back performance. So on a hot day or during track days(which I don't do) initial runs might be faster then car will slow down, but should still perform at least stage 1 level.

Gmp - the software will work but I won't be realizing the full potential of the tune. So the performance level will be in between stage 1 and 2.

I am ok with what gmp said, but if what Tom said is closer to reality (inconsistency) it might annoy to me.

I hope Giac or someone who understand how the tune works will provide some feedback. I prefer not to do just stage 1 as sw exhaust is fairly free flowing.

Thanks in advance.

 

On a turbo car, changing the stock cats is the most important thing when it comes to making additional power and lowering temperature. The muffler itself is just for sound tuning.

So if you do a GIAC software, your stock cats will run hot when you go out there at the track and the ecu will dial back the boost to control the exhaust temperature.

Both have told you the truth, it's just worded differently. The GIAC software will now recognize whether your car runs an aftermarket exhaust with a less restrictive cat. So with your SW exhaust, it might sense it's more free flowing at first, so it will give you stage 2 boost. However, with the increased boost, the ecu will also see your exhaust temperature increase more than normal since you are running the stock cat. Then, it will dial back the boost to stage 1 level.

 

Very good explaination, thank you. I don't track, I just need that occasional over boost once in a blue moon. If i can get that then I'm satisfied. I just don't want the car to go into limbo mode when the ecu detects that I have stock cats and when it's running hotter than normal due to high booster pressure.

 

@Fabspeed, will your cat bypass pipe work with the sharkwerk exhaust? You mentioned that cel might come on. Does it go away by itself or required dealer reset? Does your universal O2 spacer help with this?

 

If you are getting GIAC Stage 2 you should be getting an exhaust that is Catless (Tubi race) or with high flow cats (Europipe, GMG, Tubi Street, Fabspeed, etc). Sharkwerks is for good sound but stock cats are not ideal with GIAC stage 2

 

EP/GMG/TUBI all had 3-4 weeks wait time when I was looking. I wanted something that was in stock.

I'm trying to decide if i should do Fabspeed catless bypass with SW...

 

I hear you. They all have a big waiting list because they're in demand because they all have a good reputation for high-quality. This is not to say that the sharkwerks doesn't. It's just a very different philosophy of exhaust and one that I would not do when getting a big tune on my car because of the need for high flow cats or no cats to optimize the tune. I'm keeping my fingers crossed you can find a cat Bypass for that

 

Update - SW exhaust was not ready to ship so switched to Fabspeed catless exhaust.

 

If you're interested I can talk to Tom from champion now and see if Tubi Catless is in stock. I think he said they may have one or two. I was with him today in pompano going over the details of the work he will be doing to my car

 

Tom said he might have a used one and would let me know yesterday, didn't hear back so assumed he didn't.
Fabspeed is already ordered.
Thanks sdg!

 

No prob. Congrats on the Fabspeed!!!!!

 

Thanks! Does anyone on this forum run fabspeed catless with giac stage 2?? If so any CEL?

 

Sorry man....based on our conversation it was my understanding that you wanted an exhaust with cats. I checked to see if I had that used Tubi Street in stock, but did not. Had I known you wanted something cat-less I could have probably put something together for you.

 

Sorry for the confusion... at that point I didn't care if it was catted or catless, just wanted something by tomorrow.

Anyway, thanks for your time to explain all the pluses/minuses of giac/cobb tune.

I've decided to give cobb a try.

Will report back.

 

Come to our Atco private track rental on Oct 7 and we can have a Cobb vs GIAC shootout