Flex Exhaust Pipes??

Currently, I'm running 2 cherry bomb turbo's that are located directly under my seats. There are no tail pipes and I want to route the exhaust further back to reduce the noise and exhaust fumes further back. I want to try to exit the exhaust out the rear, under the tailgate.

I was wondering about using 2" flex pipe from the mufflers back. I purchased all the clamps, hangers, 2 tail turn down pieces and 2 6' sections of flex pipe. Everything totaled up to about $95 (each 6' flex was $21). I figure there will be about 4' of flex on each side and route up and around the rear axle and straight out the back.

Any thoughts on how long this will last. I do not run in the salty snow, but I do see a fair amount of mud. I know that a hard pipe will last alot longer, but again, I kinda want to play with the location of the discharge points to see what works best on the jeep with fumes and noise levels.

 

My dad used this stuff for years, they would hold up really well for about 3 years then rot out.

 

3 years... I can live with that. That gives me enough time to "play with it".

Should I coat it with anything before I hang it to minimize rottage??

 

Why not use the flex to get the angle of the dangle just where you want it then take that to the muffler shp and have the "real thing" bent and welded?

 

you can also get stainless flex, however it is more expensive.

 

X2 on what McRuff said. I used to run it just like you are wanting to. I don't think any coating will help, since all the vibration will just rub it off where the metal meets. That's where it usually started rusting at.

I also had problems with it getting smashed. I ran it between my leaf springs and frame, and it always got mashed when I got really twisted up. I ran it that way because there wasn't enough room to run it outside the frame (between the frame and tires). But maybe you can find a sweet spot where it's out of the way....

 

Over the weekend, I got the exhaust figured out. I took the flex from the mufflers (about 1 foot from the axle) and routed the flex up and over the rear axle and then to a turn down exiting just below the rear bumper beneath the tailgate. I used a total of 3 feet on each side. I figure by only using a total of $21.00 of flex, I'm not out much if it doesn't work out.

At least I can test this and if it works out well, I have the routing that I like and can bend hard pipe the same way and be perminate.

Thanks for all your help!!

-DrewDog

 

$21 isn't bad, but when you were saying $90 I spent around $100 to have dual exhaust made from the inside the frame headers all the way out the back. Price included two mufflers.

 

When I spent the $90, I got all the clamps, hangers and 2 turn downs. I returned one of the flex sections and a couple of clamps and a hanger. I returned about $35 worth of exhaust stuff.

All in all, I have about $65 into the dual exhaust, from the mufflers back. If / when the flex rots out, I can easily replace the $21 section of flex, or I can easily switch that section out to a hard pipe.

In my group of jeepers, I see guys replacing their all welded hard pipe exhaust systems every couple of years or so. Replacing a section of hard pipe is more involved / expensive than swaping out a section of flex. Overall, I have about $11 of flex on either side that will probably rot out faster than ~$30 of hard pipe, but I think that the flex may last more than 1/2 the life of hard pipe.

Ok, now I'm confusing myself.. I'll just run it and see what happens.

 

I’m working on a hard pipe configuration from inside the frame headers back. I really like the idea of using flex pipe to mock up the bends. I plan to do this. For you guys that have had a shop bend up your exhaust on the cheap – who did you work through? I'm guessing the chain stores aren’t the best for price…. Or are they?

Thanks,

 

I did a little mom and pop shop outside of Ishpeming Michigan. The guy was excited to work on my jeep and did a great job on it. I had him use aluminized pipe on it. It was put in two years ago and still looks about new. But in those two years the jeep has hardly been driven.

 

The biggest problem with an exhaust rotting out is wether or not the pipes get hot enough to cut down on condensation. This also holds true for engines as well, but the exhaust needs to get hot enough to be dry of moisture inside and out. Short trips (less than ten miles) frequently, don't allow the whole system and engine to fully heat up to evaporate all the moisture.
If the exhaust pipe is cold and you drive for 5 miles, wait about 15 -20 minutes the drive 5 miles back the whole exhaust didn't heat up fully so hot humid air coming out the exhaust condenses on the cooler pipe's.

The moisture run's down and pools, and we all know what happens when metal and water come together.

I've had the same exhaust on my Diplomat for 10 years cause at least once a week I make sure I get the whole engine and exhaust good and hot. (let it high idle in the driveway for a half hour or a good hard run against a slower mustang or camaro ) It will cool slowly and won't form condensation afterwards.
(My opinion) p.s. almost forgot my whole exhaust is flex pipe for the past ten years