After my rebuild, my oem cat (94) had a little bit of the brick breaking apart. The shop that did the rebuild gave me (and installed) an oem cat (93) that they had no use for. The 93 cat must have a slightly different angle on one of the flanges because the Racing Beat catback now sits closer to the gas tank heat shield than it should. It is no longer centered. When I go around a hard left turn, and accelerate, the CB bangs the shield. The CB never hit before. All of the hangers are attached properly.

I'm pretty sure that moving the CB about 1/2 inch toward the passenger side would resolve the issue. I have a couple of ideas on how to do this, but would like to explore other possibilities before doing anything. Suggestions welcomed

Thanks in advance, Adam

 

I took some wire and snugged up the hanger on the driver side / rear of the cb. That brought it over about 1/2" and it's held just fine for a couple of years now without noise or hassle.

 

Thanks Dave.

I'll take a look for a good spot.

 

Is the downpipe the same as before the rebuild? I went through a 3 stock cats and never had an issue. I do have a fitment issue that is caused by the downpipe which affects everything behind it.

 

Yep, I was gonna say the same thing. Many of the cheap downpipes don't fit well and pull the exhaust one way or the other.

Might also just want to loosen the bolts at both flanges on the cat and make sure it isn't cocked one way or the other. Also, make sure the split air pipe going to the cat isn't trying to pull the cat one way or the other.

It can also simply be that the heat shield is bent a little, and just needs to be pushed back a bit.

Dale

 

Could you heat and bend the hangers?

 

That's a lot of work and might be tricky putting open flame near a plastic bumper.

My RB CB's have both had hangers without any kind of **** or hook at the end. So the CB was free to slide a fair amount to the left or the right in the rubber hanger. Just using wire to keep it snugged to one side or the other solved the problem - at the very least it's quick and easy if it's not a long term fix.

 

I wound up modifying the outer rear OE hanger bracket by slotting its bolt holes and bending it somewhat. That wound up moving the muffler toward the right such that the LH RB bracket is at its furthest right position in the isolator.

I have had no rubbing/noise problems since I did that.

BTW, Adam, you were right - I really like the RB dual!

 

Thanks for all the replies

I don't have a cheap downpipe. I can't imaging why anyone would think that !!! It's an M2, and is the same pipe I had before the rebuild. The turbos are new. I wouldn't think that should change any angles. I didn't have any rubbing issues before the rebuild. I recently removed and reinstalled the cat to replace a bad gasket. I know that it isn't cocked, because I did the work myself. I'll check on the airpump pipe.

The heat shield isn't bent toward the catback, and it won't go any further away from the muffler.

When I looked at the passenger side rear bracket, I thought about slotting the holes. That might work. However, I am concerned that the "slop" in the hanger may allow the catback to return to where it was before.

Thanks again for all of the ideas. You guys have been very helpful

 

You probably understood what I meant, but just in case you didn't, by slotting I mean slot them horizontally, allowing you to angle the outer rear bracket outward on the bottom. This shifts its holes outward and pulls the muffler with it. I also wound up trimming that bracket a bit so it wouldn't interfere with the lips where the 1/4 panel meets the rear panel.

Dave

 

Thanks Dave. I understood exactly what you meant. That was one of the things I was already considering doing, along with maybe bending the bracket a little.

I'm glad you like the RB catback. For most of us "mature" folks, the RB is a no-brainer

 

We know you don't. Its in your sig. I mention the DP b/c some shops aren't as organized as others and could have mistakenly installed a different DP when putting it all back together.

Good luck.

 

I'll take a second look to make sure. It wouldn't surpise me if they did screw it up.

Thanks, Adam

 

I thought you had a stock cat-back? I recall that being one of the highlights of your car last time I was out there.

 

Nope. You must be thinking of another car. I have had the RB for around 5 years.

 

He was referring to Dave G.

 

I drove the rear wheels up on ramps, and got under the car this afternoon.

The first thing I did was to unbolt the passenger side catback hanger mount. After taking it off, I found the it provides ZERO lateral stability for the catback. It was very little different than if a rope were holding it in place. Slotting the holes would not help. Damn!!!! I replaced the bolts.

Next, I decided to loosen the cat to catback bolts. Maybe I could use some of the "play" in the holes to slide the catback over a little bit. There was a little room to move it, so I did, and re-tightened the bolts. I checked the clearance at the back end to find that nothing had changed. Damn!!!!

My next option was to try to wire or strap it over toward the passenger side a little bit. I found a nice place to wrap a metal strap around the 3" pipe, just forward of the muffler. There were two bolts that I could use to pull the exhaust over a bit. I made a strap out of some pliable metal stripping, drilled holes in it, and bolted it on. I checked the back end, and it looked great. Then I wiggled the muffler, and found that the strap had moved the muffler upward in addition to over. Now the muffler was hitting on it's top side. Damn!!!! I removed, and discarded the strap.

I was running out of options. I removed the catback, and I grabbed my 3 pound hammer. Using all of my best engineering skills, I beat in the heat shield, and the drivers side of the catback. I actually didn't beat on the catback too hard. Its an older style RB unit with the black canister (not chrome). I remounted it and it was perfect. Lots of clearance, and no rubbing upon shaking it. I have not driven the car yet, but it looks like the problem is solved. I guess this reinforces my old saying: "If you have a big enough hammer, you can fix anything" .

Thanks everyone for your suggestions

 

Careful you don't break that heat shield over/around the rear muffler. Its about $250 from Ray.

 

Nice! I love any solution that involves a hammer.


Paul