Flexpipes...do we really need them???

[rubensEGT1]

Yea...so maybe this weekend im getting...yep...a third flexpipe installed because they keep breaking...so I asked if I could have a solid piece of pipe welded on instead, and was told "no, because your exhaust system would explode!", is that really possible?, or is it a poor excuse for them to make money with an expensive flexpipe?, rather than $50 worth of labor and material?

[yamaha]

You need a flexpipe, reason being as the transmission shifts gear, the engine will move. On a straight pipe, this will put pressure on the exhaust, and eventually lead to cracking. The flexpipe takes this pressure away by, flexing, just get it done and be on the safe not sorry side.

[bmxdad]

Yea ... what he said, and ... our engines rock front to back. making the down pipe want to push then pull the whole system ... the flex pipe acts like a spring. I they keep braking, get a longer one. You might be pulling it apart.

[02_Elantra]

Yea ... what he said, and ... our engines rock front to back. making the down pipe want to push then pull the whole system ... the flex pipe acts like a spring. I they keep braking, get a longer one. You might be pulling it apart.

or change the motor mounts?? to stop the engine from moving as much. Unless the damage is caused by something else.

[slow 2K2GT]

I had no flex pipe for while, there are rubber hangers on the exhaust that with stiffer mounts should take up the extra pressure and flex. But if you want to be on the safe side then spend the money so you arent fixing it later.

[timebomb056]

i have the same problem that i have started to look into since i work at a universal hyundai nissan What i noticed on the later xds they added a extra mount on the exhaust to the oil pan i think before the flex pipe i have to look. With out that extra mount there is to much weight on the flex pipe causing it to leak

[rubensEGT1]

So extra mounts can be added?, if thats the case i'd have like 10 or so added to stop it from breaking & making that disgusting loud noise, I miss the sound of my cold air intake...my car used to sound like it's ripping a$$ all throughout town, it then broke itself free, strange though...now it maked a turbo noise from the pipe dangling!?! lol

[KeWLKaT]

The ''extra mount'' he is referring to is a bracket bolted onto the block, just above the oil pan, in the shape of an ''L'' which connects to the exhaust via a clamp.

[kylemorg]

There are cars that do not have a flex pipe. If I remember correctly, my friends 1997-98 200SX 1.6L Liter does not have a flex pipe.

That being said, I agree with the other comments in this thread. If Hyundai could have gotten around using a flex pipe by using a straight pipe, they would have done it. Straight exhaust pipe is cheaper than a flex pipe.

The other thing the flex pipe does is to lessen the vibration in the passenger compartment. Without it, the whole exhaust all the way to the muffler would be shifting / resonating with the engine.

[KeWLKaT]

And without a flexpipe you are one of those funny looking people who's exhaust swings aorund when they are driving, lol.

[jalmir]

You're better with the flex ... without it your exhaust will most likely broke again on a weak spot ...

As said above if it's broking often then install one a bit longer.