Getting the custom quad exhaust install coming up Monday but just got a quick question, I have OEM m5 rear bumper and the tips I got look flush and balance but the pipe will be touching the battery compartment, will this have any negative affect on the battery in the long run? Don't want the pipe to add unnecessary heat to the battery..Thanks...and sorry if it stupid question..rather ask then sorry

The battery vents Hydrogen which is very flammable, do the maths buddy lol

Hydrogen + a very hot exhaust = disaster.

The exhaust could heat up the battery compartment, not advisable IMO.

Exhaust pipes shouldn't touch anything but the hangers needed to keep them in place.

I seen people that had this custom quad stuff a whole muffler in between the spare tire and battery compartment under the car...so if that not safe?

^^^^ Not in reality. First, a battery only begins to produce hydrogen above an 80% charge rate. Second, the exhaust isn't hot enough to ignite hydrogen. The ignition point of hydrogen is 500 degrees Celsius. The CAT usually only reaches 320 degrees Celsius but the exhaust pipes at the end [where the vent for the battery is] are only about 100 degrees Celsius.

Bonsai - you do want to have some clearance between the body and the pipes. Follow the existing height of the rest of the exhaust system.

If there is an exhaust leak the fumes will have nowhere to go except through any small openinings in the body and into the car - I'd say it's not safe. I'm not sure, but there may even be laws that mandate the minimum amout of clearance.

I'd also be worried about vibration and exhaust drone.

You don't want any part of the exhaust touching the body of the car. In addition to the stuff others have already stated, it will create a lot of noise and vibration

i thanks...i guess i have to sacrificed a little bit of look of the exhaust tip by moving it out a little.

So does this mean all quad dual exhaust setups have one pipe touching the battery, or is it because of the specific angle or width of the pipe you are using, kind of a scary thought.

notch the pipe I think a member here did that.
https://5series.net/forums/topic/537...m5-rear-cover/

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