Resonator length & O2 sensor on catalytic converter question.

[ADM]

I'm buying a hiflow cat for my AWD rada next week. I know that there is an O2 sensor on the y pipe. but just needed to know if the stock cat has this aswell?. unfortunately getting under my car is a bit of a challenge and I can't get to the heat shield to remove it and see if there is one there as I don't want to buy the wrong item.

My second question is in regard to max resonator length that can be used in the AWD's. Mon's got a tiny 4" resonator after the cat and a longer 12" second resonator before the rear muffler. Magnaflow make 14" resonators and I wanted to know if anyone has had any success installing one of these or longer ones. It seems that because of the limited space in the AWDs plus the main pipe having what seems to be a 15° bend that using a long (18" or 22") resonator seems out of the question? I've already purchased the large body magnaflow rear muffler (same size as the stock) but I don't want any drone and as little rasp as possible. I understand that the system will be a tad louder when it becomes a steaight through with a hi flow cat. I just want the system to sound deep & sporty.

Any advise would be appreciated.
Cheers.

[HaydenVRX]

You have plenty of straight pipe after the cat for a longer resonator but the factory one is straight through and replacing it won't do anything but make your exhaust quieter.

Only 1 sensor and that sits before the cat. Any hi-flow weld in cat will work.

[ADM]

I don't mind a quietish exhaust and no the exhaust system on my RADA is not straight through (not the rear muffler) and it does have 2 resonators.

I was thinking of getting the weld on 200 CPI spun metal cat and flanging it which would create enough room theoretically to fit a 14" magnaflow resonator and if need be, add an additional 6" magnaflow race resonator before the rear muffler (which would replace the stock 12").

I'll get my fabricators to prep a stainless system for me as I can buy the tubing cheap enough through work. I just needed to get some things cleared up like the o2 sensor (which Hayden answered- thanks).

I am of the uninformed opinion that this set up would still be louder than stock but well within noise limits and will give me the kind of power and sonic upgrade that I am looking for.

Just trying to get some ideas from people who have installed these or similar.
Anyone with an AWD and upgraded exhaust system offer some insights?

[alscall]

Have sent you a link with some pics of the underside of my AWD so you can see what I managed to fit in there.

[ADM]

Thanks for that. the link was very helpful. just a quick question. is the cat you had fitted in the pics a 5" round? I was hoping to get a 5" round cat under there. I already have the hm perry headers and y pipe fitted. the rest of the system inc engine is stock for now

[FamilyWagon]

Just a bit of advice mate.
After spending thousands on exhaust mods and countless days wasted at exhaust shops, I found the best setup for the AWD is using HM headders, stock after that inc stock cat, and just have the genuine sports muffler on. ( single outlet ).
Anything other than that will make it loud, give it an annoying boom and will make it sound terrible and raspy.
I put a hi flow cat on and it made no difference at all other than making it sound worse.

[munkeymanz]

Well that's promising, cause I'm getting a 6G75 conversion done on my TW AWD in a couple of weeks with HM Headers (already ordered) and stock cat-back. I want it quiet as.
Spending thousands on exhaust mods would only pay off if you got a tune as well.

[FamilyWagon]

Yeah had a 98 skr tune as well as ralliart cams. That's the perfect combo munkyman. You won't better the sound or note.
After all the time and money I spent and wasted on the exhaust I ended up going back to stock with the HM headers and genuine sports muffler.
I know the temptation is there to mess with it but you won't better the stock note/sound. The AWD is a very hard system to get sounding tough or nice.

[FamilyWagon]

Oh yeah and included in that time and money wasting was dyno runs and once again, no improvement messing with exhaust. The only thing that improved power outputs was HM'S and sports muffler.

[HaydenVRX]

Anything should sound good as long as you have 2 resonators and 1 rear muffler.. Just make the rear muffler small if you want it loud or big if you want it quiet.
It's when people take out middle mufflers/resonators the cars get raspy.