How to keep my exhaust pipe from getting crushed?

[1973Guppie]

Hi Everyone,

now that I am using my truck more and more off road my exhaust pipe is getting the brunt of my damage allotment. I am running a 4x4 labs rear bumper and have the pipe exiting on the passenger side rear corner. It just gets flattened when I hang my big butt up on rocks.

Looking for ideas on how to keep this from happening in the future? Curious to see what other folks have come up with? I think I remember seeing someone have the pipe exit out the side of the truck higher up via a drilled hole. I searched but did not find a specific thread on this topic. I suppose the cleanest route would be to cut a hole in the side wing of the labs bumper and exit there. Not sure though how much rattling this would cause as I drive down the highway? Another thought was to make some heavy duty "loops" of pipe on the rear bumper corner area to surround the pipe and keep it from getting crushed.

My truck is not a hardcore rockcrawler so keep that in mind. But this is an area I would like to figure out so I don't rebend my pipe every time I go out.

Thanks for your ideas and thoughts! I will post a few pics of the carnage tomm.

Noah

 

[Phildoh]

Sorry it's not the best pic, but I picked up one of those "turndown" type exhaust tips and when I re-did the exhaust I had the muffler guy run it (tailpipe) up higher, and then put the tip on so it sits really close to flush on the bottom edge, tucked behind my rear crossmember/bumper tube. Helps a lot and I've barely touched it on the trail.

 

[rockstate45]

I'll have to snap a couple pictures when I get back in town but I basically did the same thing when I had my exhaust reworked. My exhaust is tucked up in a manner that if I crush it, I'm gonna be having a bad time. He reworked the back half of the exhaust and redid the hanger for like $65 so it was fairly inexpensive (YMMV).

 

[Dork]

Draw an imaginary line from where your tire touches the ground to the lowest spot at the back of the truck. That's basically your departure angle. If your pipe comes out the side inside the new imaginary triangle above that line, you will be likely fine in almost all situations.

 

[bloc]

The drilled hole idea might be from @RockJock82 (I think, sorry if it was someone else's idea) for people with 4x4Labs bumper. Go to 2:48 (though the whole video is great):

My exhaust is too large to find a bend tight enough to get over the frame and catch that spot.. (or at least for the amount of work I want to put into it) and I have plans for a subtank or jerry can holder under there, so it'll be dumping behind the pass side rear tire as high up as I can get it. It isn't finished, but pointing in that general direction

 

[icorradoi]

I had my local muffler guy add a hanger and a bit of pipe with a downturn at the tip. It sits almost level with the bumper and can be pushed up a bit without any real damage occuring, other than some scrapes. Let me know if you want any additional pics.

 

[Tools R Us]

Got a sawzall, cut it off short of the pinch point?

 

[2fpower]

look at my post 157. I reused all stock componets, flipping mount to the inside of the frame member.


The official Boost build thread

 

[1973Guppie]

thx guys, for those that cut the pipe shorter and used a downturn, have you had any issues with exhaust gas getting inside the car at idle? that is my main concern as I do carry my kids and family in the car quite often. I have read before that exhaust "should" point outward from the edge of the back of the car to allow exhaust to escape properly.

 

[Mandrake]

Mine ends in a down turn behind the muffler and before the rear axle. I found a shop to pass it, so . The part where it goes under the frame still gets beat up, but I've yet to smell any exhaust in almost two years with it like that. One thing I will say- down turned exhausts kick up a lot of dust.

 

[Mandrake]

I have read before that exhaust "should" point outward from the edge of the back of the car to allow exhaust to escape properly.

In theory, yes, to take advantage of the low pressure that exists behind a vehicle moving through the air. However, to best realize that effect, the exhaust would have to be exiting somewhere up around where the plate is. The effects would be marginal, or would only work in a narrow speed range at a certain engine load and RPM- much like true ram air. Aerodynamics around vehicles are funny- it's not the way you'd always think it'd be, especially when dealing with what happens on the lower half of the vehicle.

Considering the speed range in which our Cruisers operate, the amount of air going under the truck and the massive turbulence everything under there creates, I'd say you could pretty much point the exhaust any way but directly forward without detriment to performance.

 

[icorradoi]

No issues with my set up. I can smell the exhaust outside the truck when the cruiser is cold, but do not smell it inside.

 

[baldilocks]

 

[CycloSteve]

Here is my OE exhaust, modified by Luke when he installed my bumper.

Here is when I was running the first EMS 2.5" stainless steel setup

2nd EMS setup was trail-modified at Sourgrass, and I removed a few inches off of the tip.

Now running 3" setup with the diesel, and tucked completely up and out of the way. Will have to take a pic of that one.

 

[shocktower]

I am getting a new exhaust, and i wonder how, it will survive 3" mandrel bent

 

[Redgrrr]

This isn't for everyone or every state...I just had my exhaust done from the down tubes back. The noise "drone" from the exhaust already annoys the wife but at least my shenanigans won't get the tail pipe ripped off or crushed.

I think the drone has to do with the magna flow parts and the fact that It doesn't go all the way out the back. Gotta build sliders to protect the Y pipe next.

Going wheelin this weekend so gonna have to be careful on the passenger side for now.

 

[RLMS]

This thread should have some post's with carnage pics as well. I'm just saying that because I have a good pic of carnage. For others who have a factory rear section still intact, can see before and after pics

Justin

 

[chap79]

Cut, shortened, and rewelded.

 

[BILT4ME]

Don't forget that there is also heat to deal with out of there. I have the stock exhaust on mine and on a camping trip, I had my son's wheelchair on a hitch rack on the right side. It was 100° outside during that trip and after 1-1/2 hour on the interstate, we got home, and the left front tire of the wheelchair was dripping on the ground. It actually MELTED the wheelchair tire! The WC tire was at LEAST 18" from the exhaust port, but straight back.

The exhaust WILL burn off the paint in the area it dumps. Just look at all the Toyota pickups from the late 80's with the burnt paint on the left rear fender where it would heat the fender and burn it off.

 

[shocktower]

Don't forget that there is also heat to deal with out of there. I have the stock exhaust on mine and on a camping trip, I had my son's wheelchair on a hitch rack on the right side. It was 100° outside during that trip and after 1-1/2 hour on the interstate, we got home, and the left front tire of the wheelchair was dripping on the ground. It actually MELTED the wheelchair tire! The WC tire was at LEAST 18" from the exhaust port, but straight back.

The exhaust WILL burn off the paint in the area it dumps. Just look at all the Toyota pickups from the late 80's with the burnt paint on the left rear fender where it would heat the fender and burn it off.

Yes they melt things, my concern is the black soot #Dieselworries