Magnaflow Catback on Convertible

[Greg C]

Just wondering if anyone has fitted a cat back exhaust yet on the convertible? I had mine fitted on Thursday - looks & sounds great. Had to remove chassis brace to remove standard exhaust but put back on once new exhaust was fitted. First real drive was to Goodwood this weekend & when on bumpy roads sounds like there is a knocking sound. I think it must be the new exhaust touching the chassis brace when on bumpy roads as there will be a small amount of flex in the exhaust due to the rubber mounts. I will see if I can adjust it as annoying- I don't think it is doing any damage.

 

[djone101]

We've fitted a couple of systems to convertibles - the routing around the diff and subframe area is definitely tighter than on the coupe. There is certainly quite a bit less clearance so getting it sitting right takes a little longer. When the system heats up it will grow rearwards too as it gets hot. Can be as much as 10mm when you get to the tailpipes. The hangers will allow for this as the bars will slide through the rubber isolators but you may find clearance reduces when it's hot.

 

[Manders Mustang]

Just wondering if anyone has fitted a cat back exhaust yet on the convertible? I had mine fitted on Thursday - looks & sounds great. Had to remove chassis brace to remove standard exhaust but put back on once new exhaust was fitted. First real drive was to Goodwood this weekend & when on bumpy roads sounds like there is a knocking sound. I think it must be the new exhaust touching the chassis brace when on bumpy roads as there will be a small amount of flex in the exhaust due to the rubber mounts. I will see if I can adjust it as annoying- I don't think it is doing any damage.

I have the same, I've put it down to the exhaust tips knocking on the valance on bumps and such.

My worst fear would be the back pipes hitting the diff...
[MENTION=8914]Big_G[/MENTION] any your end?


Also may help if you've got a picture on the exhaust under your car, i'll take one of mine tonight and can compare.

If yours is knocking, and the stock one wasn't, maybe something wrong - but may also be that the tips on this exhaust are mammoth, so probably just knocking the valance.

 

[Greg C]

I have the same, I've put it down to the exhaust tips knocking on the valance on bumps and such.

My worst fear would be the back pipes hitting the diff...
[MENTION=8914]Big_G[/MENTION] any your end?


Also may help if you've got a picture on the exhaust under your car, i'll take one of mine tonight and can compare.

If yours is knocking, and the stock one wasn't, maybe something wrong - but may also be that the tips on this exhaust are mammoth, so probably just knocking the valance.

Just been under the car - very tight where the chassis brace is on both sides. I can imagine that going over a bump, the exhaust will move a little bit on its rubber exhaust hangers & this is causing the noise when it briefly touches the brace. I have just tried a bit of exhaust silencing wadding that I had in the garage around the area where it is a little tight & been for a quick drive. Definitely better as providing something to cushion the bumps. Not a long term fix but will see how it goes- definitely not the tips touching the rear valance in my case- they don't move at all. Car is going in to Modurstang in a few weeks for underseal so will see if they can improve the installation of the exhaust as they need to take it off anyway.

 

[Manders Mustang]

Just been under the car - very tight where the chassis brace is on both sides. I can imagine that going over a bump, the exhaust will move a little bit on its rubber exhaust hangers & this is causing the noise when it briefly touches the brace. I have just tried a bit of exhaust silencing wadding that I had in the garage around the area where it is a little tight & been for a quick drive. Definitely better as providing something to cushion the bumps. Not a long term fix but will see how it goes- definitely not the tips touching the rear valance in my case- they don't move at all. Car is going in to Modurstang in a few weeks for underseal so will see if they can improve the installation of the exhaust as they need to take it off anyway.

Will take a look under mine, or have someone drive behind me, I can't move the tips for the life of me more than like 1mm, but when you're hitting a jagged bump, could be that! Never know! To be honest though the knocks I used to hear when I'd first got it have all but stopped now, haven't heard one in the last few days driving!

 

[Greg C]

Will take a look under mine, or have someone drive behind me, I can't move the tips for the life of me more than like 1mm, but when you're hitting a jagged bump, could be that! Never know! To be honest though the knocks I used to hear when I'd first got it have all but stopped now, haven't heard one in the last few days driving!

You will not have the chassis brace so might be touching somewhere else under the car- unlikely though. Mine is going to Ford on Wednesday afternoon for free 1500 mile check over - I won't mention it to them if I still have a knocking noise as will get Modurstang to sort if still a problem. Really only taking it on so I can get them to look at wear on seat bolsters & to show salesman the mods on the car hopefully will get the Steeda strut brace soon & then nearly finished mods!

 

[Manders Mustang]

You will not have the chassis brace so might be touching somewhere else under the car- unlikely though. Mine is going to Ford on Wednesday afternoon for free 1500 mile check over - I won't mention it to them if I still have a knocking noise as will get Modurstang to sort if still a problem. Really only taking it on so I can get them to look at wear on seat bolsters & to show salesman the mods on the car hopefully will get the Steeda strut brace soon & then nearly finished mods!

Yeah, i'll listen out for mine again, but i'll guess that it'll be the valance still, wont know till somebody drives behind me, usually only ever happened on pot holes so could be something else entirely and maybe down to me driving with windows open / radio off since having exhaust and having not heard it before hand! Other one would be diff hitting back pipes, but that's stupidly unlikely.

Will listen tonight on my drive home hopefully it's sunny so can have windows open! I know it won't hit on a brace as she's not a 'verte.


Only other knock I'd ever heard is turning out full lock of my driveway in a morning, which is down to some fluid being cold or something.

 

[Big_G]

Nope all good here, no knocking or anything from the exhaust. In fact the only noise i occasionally get is a very slight whine when the car is cold, think its the drive shaft but it goes away as a soon as the car is warmed up.

 

[Manders Mustang]

Nope all good here, no knocking or anything from the exhaust. In fact the only noise i occasionally get is a very slight whine when the car is cold, think its the drive shaft but it goes away as a soon as the car is warmed up.

I don't get that :lol:!

Right, now I'm gonna be properly listening out when I drive, no music, no nothing :frusty:

 

[Big_G]

I don't get that :lol:!

Right, now I'm gonna be properly listening out when I drive, no music, no nothing :frusty:

I only very occasionally get it after the car has been standing overnight and if it's quite cold morning ... which at the minute it isnt, so I haven't heard it for a while.

 

[Manders Mustang]

I only very occasionally get it after the car has been standing overnight and if it's quite cold morning ... which at the minute it isnt, so I haven't heard it for a while.

I'm half tempted to livestream, but I haven't heard any bangs for a while recently, it was only after I first put it on, day after it was gone, haven't heard it since!

If my Exhaust was hitting the valance I'd have marks on the valance, and probably the exhaust, which i'll check for tonight.

It's probably my paranoia to be honest !

As for greg... disadvantages of a convertible ahy ! :headbonk:

 

[Manders Mustang]

Correction, zero knocks or bumps or clanks, and I went over pot holes.

 

[Greg C]

Correction, zero knocks or bumps or clanks, and I went over pot holes.

Glad yours is ok now. Just got in from work & no knocking with my temporary fix (that may be permanent!) but didn't have any pot holes. Handling wise, coupe is better than convertible & not sure what difference the chassis brace actually makes other than to foul exhaust if you don't line everything up 100%.

 

[MagnaFlow]

Glad yours is ok now. Just got in from work & no knocking with my temporary fix (that may be permanent!) but didn't have any pot holes. Handling wise, coupe is better than convertible & not sure what difference the chassis brace actually makes other than to foul exhaust if you don't line everything up 100%.

The chassis brace doesn't do much for handling, and some owners take it off completely. To fix the rattle you may have to loosen the clamps on your catback, rotate the pipe positions slightly, and re-tighten them starting from the front of the car back.

You can also use a couple washers underneath the brace to space it out away from the pipes, but should not be necessary for proper fitment. Let us know if the rattle is fixed, and if there are any questions we can answer!

 

[Greg C]

The chassis brace doesn't do much for handling, and some owners take it off completely. To fix the rattle you may have to loosen the clamps on your catback, rotate the pipe positions slightly, and re-tighten them starting from the front of the car back.

You can also use a couple washers underneath the brace to space it out away from the pipes, but should not be necessary for proper fitment. Let us know if the rattle is fixed, and if there are any questions we can answer!

Thanks for the fitting advice. I did think about using washers under the brace but will see about loosening the clamps etc first. Without a ramp, it is difficult so will have to wait a couple of weeks until car is going in for other work.