Can you unbolt it and look into it? (From the engine side)

See if it's melted or clogged (There should be a very fine honey comb pattern to it, like a window screen, but as long as the body of the cat instead of flat.)

Shine a bright flashlight into the exhaust end and see if you can see it from the engine side.

 

Exhaust i coming out in the back, but the everything between the cat and the downpipe is simply sizzling after 5 minutes of slow driving, i cant remember knowing or noticing that it should all be that hot, ill have a look tonight thanks for the tip

 

uuuuuhhhmmm. The sensor i have on my downpipe isnt hooked up anywhere, what does this mean?

 

It means your car will get worse gasmileage on the highway. You need aftermarket downpipe and silencer.

 

im Getting the REVII Racing Beat downpipe 3" and im getting a new cat and using my old Ypipe with mufflers from the Racing Beat exhaust ive got now, manufacture some pipes too go between these parts...would that work?

 

From my understanding the RB won't bolt up to the stock cat? I could be wrong. Also why have a cat? You should just set if up to bolt the cat on when needing smog or find a used one(you already own one) and hollow it out so it will pass visual inspection. If you wanted to you could just hollow out the cat you have now and it would stop glowing. If you have em gut out the precats. Buy some headerwrap and wrap the stock pipe like in my pic.

Also don't boost the car cause backpressure could put stress on the engine. Have you ported your wastegate?

 

Dont boost the car, the f*ck u mean dont boost the car? ur scaring me man, i cant boost the car if i change too the RB downpipe with a new Racing Cat?
Or are you just talkin for smogs?

 

Genral rule is if get rid of the cats you will have boost creep. No backpressure just lets the turbo boost as much as it wants. The s5 wastegate should be ok But I would have it ported anyways. S4 you def want to port or else boom. If you have ported your wastegate then don't worry. Again, this is just if you have NO cats.If you have a high flow cat you should be ok and not have to port the wastegate or worry much about boost creep.


If you can just pull the turbo & front half of exhaust. Port the wastegate and gut the cats. You should also plug the hole in the cat. If you know how to do the work it's free and will also solve your heat problem.

 

It doesn't. All of RB's headers and downpipes are ~3.5" too short to reach the stock cat flange. They're supposed to be used with their presilencers, which are longer than the stock cat.

Also, a 3" DP obviously needs to be used with a full 3" exhaust system. Otherwise, some custom necking down has to be done. Bolting a 3" flange to a 2.5" or 2.25" flange will cause massive exhaust leaks.

 

I got an S5 so i should be ok? Im still running at stock power with a small streetport, the engine produces about 240 bhp atm. I got 3rd party valve cause my wastegate wasnt letting out on the correct boost pressure but we "fixed" that with this valve.


Oh yeah im doing 3" all the way until the Y-pipe wich splits up into 2x 2.5" wicg makes up 5" so i should be good....? And screw the stock cat, its gone, outta the discussion all together hehe, im getting a new one and fabricating the pipe inbetween too make the pieces fit

 

NO YOU DID NOT FIX TEH BOOST CREEP WITH A 3RD PARTY VALVE! I will ask this. Was the stock cat removed when finding out the 3rd party valve released enough pressure? What I am saying is when you remove the cat you MAY find that the boost creep can happen. Esp with 3" all the way.

My s4 has a very very ported s5 turb and without a streeport engine. With the smaller 2 1/2" full RB system my boost goes above stock sometimes( cold morning etc). Just be careful when you put your new system on is all I'm saying.

 

I'll just add that there is absolutely nothing short of porting the wastegate, or using an aftermarket manifold & aftermarket wastegate, that will stop boost creep. Boost controllers only turn the boost up, and with a newly freed up exhaust, you'll defintely see it. The S5 wastgate has 5x more area than the S4, but it's still not big enough. Mine is ported out as far as possible & the cover plate was milled to allow the wastgate door to open further. The result is that it doesn't creep at all on me, even though I have an open intake and a 2.5" open exhaust.

 

Naw u got it all wrong, i havevnt fixed boost creep, i dont HAVE boost creep cause i still got the stock exhaust with the rb catback, but on stock boost the turbo wouldnt boost at all cause the wastegate wasnt releasing at the correct pressure so i added a 3rd party valve too control the boost release. now im pretty green so all the terms and such that i use may not be correct.

 

I think you mean 3rd party BOV (blow off valve). The wastegate is inside the stock turbo hotside. So, just watch out for boost creep when you install the exhaust. Do you have emmissions tests in your country?

By the way nice ride!

 

Almost hehe, i have some 3rd party device cause the wastegate doesnt let off at the correct pressure,, hope that explains it, doesnt matter really im getting a new HKS 40mm wastegate which will fix that problem and i can remove the 3rd party valve??

Yeah we got emission control here and they are strict as f*ck, especially now when the whole countrys policeforce is witchunting tuned cars right now, ive been pulled over 3 times this month already, no dynotrip yet tho luckily.

I should only be at about 240 bhp now so shouldnt cost me the world but they fine 200 usd a hp extra found in your engine