Header install

[dragon22]

Hey guys,

I bought an ARH header and hi flow cat setup and am going to put them on my car. I am already running an MBRP cat-back exhaust system. Here is my dilemma...the hi flow cats are 3" inlet and 2.5" outlet. Is the 2.5" outlet the same size as the factory cats?

I should know. I should remember. But for the life of me, I cannot! I am assuming the MBRP system fits OVER the factory cats.

Anyone know for sure?

OR, do we have to expand something to get the new hi flows to connect to the MBRP?

[SummoneR]

IF I recall correctly, the MBRP is a 2.5" ID (Inside Diameter) and the factory cats are a 2.5" OD (Outside Diameter) So the MBRP fits over the Factory cats, then there is a 3" band clamp that goes over that. So you have some high flow cats? or just a straight pipe with a reducer to the 2.5"? If so it is the same 2.5" as the factory cats so that it will mate up with the factory 2.5" exhaust. or your cat back MBRP etc. So you should be fine.

I have some LG headers with High Flow cats and a reducer. I am hoping my reducer fit with my MBRP as well. If not I have some 3" Butt connection band clamps, so if they are both 2.5" OD then I am covered. My hope is that they will slide into one another, much better connection.

[dragon22]

I guess what bothers me is I held my hi flow cat up to the end of an old SS exhaust system a friend has and they mated up perfectly. One would not go inside the other. I was wondering at that point if our stock system was just butted up against the factory cats and held there with the wide band clamp that is factory. (If that makes sense.) LOL

I'm with you, I'm sure the MBRP fits over the factory cats. And in my thoughts, if it does, then it will fit over the hi flow cat as well. There were no instructions in the box to tell me if they butt ends, have to expand...nothing. LOL

I'm going for the gusto on Wednesday! I'll find out for sure then!

Thanks for your insight.

[SummoneR]

The cats and OEM are the same... oh man might not be good... I am trying to remember if the OEM was a lap or a butt connection. The clamp had a tab type retainer to keep the clamp from sliding, so it may have been a butt connection, if so you are in luck because the MBRP will fit right over it.

Let us know how it goes, I may not be able to get to mine until next weekend. It's raining this weekend and my reducers have not come in the mail, and hopefully they have an O2 mount on them if not it may be even longer before I can do it...

I am told LT headers and MBRP exhaust are loud! I am excited about that, but I hope it's not too loud.

No problem! I hope I helped in some way, I am in the same boat.

[dragon22]

Okay, I remember now after looking at the following picture.

The exhaust DOES butt together with the factory cats and there is a wide band clamp to hold them together. The tab we had to lift, was indeed, insurance against the system coming apart.

The band clamp stayed on the cat and the MBRP system slid inside. So...when we put out headers and cats on...or eliminator pipes...the 2.5 inch OD of the cat will slip inside the band clamp and the 2.5 inch OD of the MBRP system will slip inside the other end of the band clamp, then we clamp it down!

Going to be something I'll be checking every oil change at least, to make sure nothing is backing out. LOL

http://i466.photobucket.com/albums/r...Exhaust/17.jpg

[dragon22]

Originally Posted by SummoneR

The cats and OEM are the same... oh man might not be good... I am trying to remember if the OEM was a lap or a butt connection. The clamp had a tab type retainer to keep the clamp from sliding, so it may have been a butt connection, if so you are in luck because the MBRP will fit right over it.

Let us know how it goes, I may not be able to get to mine until next weekend. It's raining this weekend and my reducers have not come in the mail, and hopefully they have an O2 mount on them if not it may be even longer before I can do it...

I am told LT headers and MBRP exhaust are loud! I am excited about that, but I hope it's not too loud.

No problem! I hope I helped in some way, I am in the same boat.

Loud? It's funny. Everyone says they can hear me coming from down the street with my MBRP exhaust on. Inside the car, it doesn't sound that bad. I'm with you though. I hope it isn't too loud. Well, loud...but not obnoxiously loud! LOL

As for putting the system together, I'm 100% positive that is how it will go together. I'm just concerned about them slipping apart, but if it looks like they are, I'll get a shop to put a tack weld on either side. Someplace that I can get to it with a die grinder to nip the weld off if I have to service the system.

If you're as happy with the MBRP exhaust as I am, I'm sure we'll it with headers! LOL LOL

[SummoneR]

Ah now you mention it, that's right both slid into the clamp. You're good to go then. NICE!

Yeah the MBRP sounds great from outside the car, drown kind of sucks, I plan to use a helmholtz pipe to tune out the drone, it's too much after a 5 hour drive.

I've had my catback on for almost three years and the connection has not slipped at all. So you should be okay as long as you tighten it enough.

I agree Everyone loves the sound outside and I do too when my windows are rolled down. headers are just going to make it sounds even sweeter.

[Brianskeet]

I did some measuring to make sure the cat and the exhaust both slid into the band clamp the same amount. Wanted to give it the best chance of not slipping. My instructions from Corsa said to torque all the clamp bolts to 45 lbs. That is pretty firm so it should be good to go. Not a bad idea to take a good look around under there at every oil change.

[dragon22]

Thank you sir. Confirms what we thought. It's more and more encouraging! C'mon Wednesday! LOL