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Old 07-28-2005, 09:17 PM   #1
DevinM
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Cutting holes in crossmember for exhaust.

My truck is a "weekend driver" that only gets out when it's nice and sunny, and I drive less than 1000 miles a year. I don't race it, I just enjoy it.
Now, that being said....I just purchased a set of 3/4 headers from ECE and want to cut holes in my existing crossmember to run the exhaust through. My truck is dropped 4/6 and my current long headers are too low and banged-up.
Will I be OK? Should I re-enforce it? How would someone re-enforce it?
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Old 07-28-2005, 10:41 PM   #2
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Project CopperHead on Trucks TV had a cross-member that was cut and reinforced for the dual exhaust. I'm not sure what was used but it looked like a 1-2" section of 4-5" dia. pipe was welded into the holes to strengthen it. I think ECE offers a cross-member designed for lowered trucks.
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Old 07-29-2005, 04:50 PM   #3
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Quote:
Originally Posted by Sweet72
Project CopperHead on Trucks TV had a cross-member that was cut and reinforced for the dual exhaust. I'm not sure what was used but it looked like a 1-2" section of 4-5" dia. pipe was welded into the holes to strengthen it. I think ECE offers a cross-member designed for lowered trucks.
I thought Copperhead was running the custom cross member from ECE
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Old 07-28-2005, 11:05 PM   #4
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Sweet72, I spoke with the guys over at ECE. I advised that I was tight (very tight) on money, and could only afford the headers. They told me that since my truck is not a "daily driver", I could cut holes in my existing crossmember and not have any issues.
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Old 07-28-2005, 11:15 PM   #5
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What about this?
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Old 07-29-2005, 03:49 AM   #6
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It probably would be OK as you state it's not a daily driver and you don't race it. But I don't think I'd ever feel comfortable without reinforcing the crossmember. Whether it be boxing it (which would be real easy but overkill) or just welding some plate over the hole and larger than what the hole will become. I've got the ECE crossmember pictured above and will be modifying it also as I don't trust it to stay together with what I plan on subjecting it to.
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Old 07-29-2005, 10:21 AM   #7
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brothers and ece makes a kit, but they're for lowered rides. if you're at stock stance the crossmember's hole for the drive shaft would be too high.
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Old 07-29-2005, 11:11 AM   #8
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Quote:
Originally Posted by matthufham
brothers and ece makes a kit, but they're for lowered rides. if you're at stock stance the crossmember's hole for the drive shaft would be too high.
He said he's lowered 4/6 in the first post, but he doesn't have the cash to buy an aftermarket crossmember.

I've cut a bunch of the stock ones and never reinforced the crossmember, without problems.
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Old 07-29-2005, 12:21 PM   #9
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Quote:
Originally Posted by Tx Firefighter
He said he's lowered 4/6 in the first post
the poster above me didn't say if his truck was lowered
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Old 07-29-2005, 01:03 PM   #10
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Quote:
Originally Posted by matthufham
the poster above me didn't say if his truck was lowered

If you are referring to me, info in my sig. Fatman Fab on front w/coilovers and HTH kit in the back. Will have around 550rwhp N/A and around 800rwhp with some nitrous assist. And the crossmember that Brothers sells is ECE's. Ask me how I know.
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Old 07-29-2005, 01:45 PM   #11
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Quote:
Originally Posted by 68LSS1
Ask me how I know.
ok, how do you know? because they look exactly alike and the pictures are very similar?
also you got a nice little truck started there i saw the pics.

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Old 07-29-2005, 11:19 AM   #12
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mine is just a stock cut one and 600 rwhp later... no problem.
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Old 07-29-2005, 12:55 PM   #13
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FirstGen's truck is definetely lowered. it's an awesome truck too with a ton of power.
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Old 07-29-2005, 01:34 PM   #14
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Didn't 3/4 tons come braced fromt he factory? You could find a pair of those out of a junk yard. You could also make and weld in some metal to box in the crossmemeber. Also, I think you'll have to mount the exhaust solid to the frame. That means you'll have to install flex joints like they did on Trucks. I'm not sure what they cost.
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Old 07-29-2005, 05:10 PM   #15
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it probably did since ece basically provided everything for that truck.
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Old 07-29-2005, 11:33 PM   #16
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Copperhead isn't running the ECE crossmember. They advertised it on TRUCKS! TV after Copperhead was finished. It has a modified stock piece.

I had a friend modify his. He cut holes big enough for 3" pipe. Slid a piece of 3" pipe about 3-4" long and welded em in. He was only gonna use 2 1/4" pipe for his exhaust so he had plenty of clearance. I'm gonna do the same but I'll use bigger pipe so I can run 2 1/2" exhaust.

Welding a piece of pipe in actually strengthens the crossmember. Probably better than it was to begin with IMO.
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Old 07-30-2005, 04:30 PM   #17
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Quote:
Originally Posted by 68Stepbed
Copperhead isn't running the ECE crossmember. They advertised it on TRUCKS! TV after Copperhead was finished. It has a modified stock piece.

I had a friend modify his. He cut holes big enough for 3" pipe. Slid a piece of 3" pipe about 3-4" long and welded em in. He was only gonna use 2 1/4" pipe for his exhaust so he had plenty of clearance. I'm gonna do the same but I'll use bigger pipe so I can run 2 1/2" exhaust.

Welding a piece of pipe in actually strengthens the crossmember. Probably better than it was to begin with IMO.
Thanks for the clarification.
Here is the best pic I can find of Copperhead's setup. I should have looked closer when it was here in February

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Old 07-30-2005, 12:47 AM   #18
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ok, I have every copperhead episode on the DVR, I will have to settle this!

give me a little bit to go through them all and find it...
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Old 07-30-2005, 12:53 AM   #19
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68stepbed is correct! man that's an awesome truck!
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Old 07-30-2005, 05:38 AM   #20
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My truck has holes cut in the crossmemeber and its just fine. I do want to note, that I don't have much horsepower either.

Here is a bad picture of it:

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Old 07-30-2005, 05:48 PM   #21
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One thing to note on Copperhead's exhaust design. Notice that the exhaust is attached to the drivetrain (except for whatever hangers are used aft of te mufflers). The headers are of course bolted to the heads and a hard bracket off the tranny for additional support. This allows the exhaust system to move with the drivetrain as opposed to being stressed when it gets "torqued" over. A good idea and well designed.

One other thing, I assumed a trailing arm suspension. If the truck is a leaf spring set up I wouldn't think twice. But as the trailing arms mount to that crossmember on the coil spring trucks I can't imagine what sort of stress that crossmember could be under especially subjected to launches and high hp/tq engines. Daily driver would probably be fine but I don't think I'd want to push it with a vehicle that also has weekend track duty.
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Old 07-31-2005, 09:51 PM   #22
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Exclamation Just an Idea

Here's what I would do:

First if you must cut holes in a crossmember that has trailing arms attached to it, cut the holes ROUND and at least 1/4" larger than the outside diameter of the exhaust pipe, (1/2" all the way around would be better). Next Fab up some pieces of 3/16" to 1/4" plate that have the same diameter hole cut through them. Make the plates as tall as you can, and still be able to weld them all the way around onto the crossmember and inside the hole. These 'scabbed' on plates will reinforce the crossmember at the exhaust pass through area and probably make it stronger than it was uncut.

Just my $.02
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Old 08-02-2005, 10:06 PM   #23
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Thanks alot folks, I appreciate it greatly. I have trailing arms, so I WILL re-enforce the crossmember.
I especially like (2) ideas. 68Stepbed's suggestion of cutting 3" holes and welding 3" pipes in place. Cause, I will not be using anything larger than 2 1/2" pipes.
The other being plates, cut 1/4" larger than outside diameter the freshly cut holes, and welded in place.
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