Exhaust Flex Pipe
Thread Starter
|
Senior User
Joined: Apr 2002
Posts: 414
Likes: 0
From: Austin, TX
Exhaust Flex Pipe
Anyone ever use a flex pipe in the construction of your exhaust system? Sure seems like this could make the fabrication of a DIY sytem alot easier by eliminating some mandrel bends. I am wondering how they hold up.
Specifically, I am thinking flex pipe off the headers to straight tube to Flowmaster Hushpower muffler to straight pipe to 45 degree mandrel bend (off the shelf) exiting under running board in front of rear fender a la a Lightening. In this case all I would really have to do is weld the flextube to a reducer coming off the headers.
Sure seems easy. What am I missing? In theory it would be easy to add an x-pipe.
Tim
Specifically, I am thinking flex pipe off the headers to straight tube to Flowmaster Hushpower muffler to straight pipe to 45 degree mandrel bend (off the shelf) exiting under running board in front of rear fender a la a Lightening. In this case all I would really have to do is weld the flextube to a reducer coming off the headers.
Sure seems easy. What am I missing? In theory it would be easy to add an x-pipe.
Tim
Postmaster
Joined: Jun 2004
Posts: 4,190
Likes: 2
From: Riverside, So Cal
Tim -
The steel flex pipe I have seen looks a lot like the universal radiator hoses with diametric ridges that allow it to flex. Is that the stuff you mean?
I agree that it would make fabrication easier. However the ridges in it that allow the easy bending make for a lousy flow path. The ridges cause eddys and turbulence along the wall reducing the effective tube diameter available to flow the gasses. As the flow increases, the effective diameter is reduced even more.
I wouldn't use it unless I was running a very large diameter tube (3-4") and low rpm's.
The steel flex pipe I have seen looks a lot like the universal radiator hoses with diametric ridges that allow it to flex. Is that the stuff you mean?
I agree that it would make fabrication easier. However the ridges in it that allow the easy bending make for a lousy flow path. The ridges cause eddys and turbulence along the wall reducing the effective tube diameter available to flow the gasses. As the flow increases, the effective diameter is reduced even more.
I wouldn't use it unless I was running a very large diameter tube (3-4") and low rpm's.
Thread Starter
|
Senior User
Joined: Apr 2002
Posts: 414
Likes: 0
From: Austin, TX
Randy
Actually I also am familiar with the flex pipe you are talking about but this stuff is major league different. Stainless woven with weld on, slip on or flange ends.
http://cgi.ebay.com/ebaymotors/2-5-x...QQcmdZViewItem
I'm thinking about 2.5" tubeing.
Tim
Actually I also am familiar with the flex pipe you are talking about but this stuff is major league different. Stainless woven with weld on, slip on or flange ends.
http://cgi.ebay.com/ebaymotors/2-5-x...QQcmdZViewItem
I'm thinking about 2.5" tubeing.
Tim
Cargo Master
Joined: May 2003
Posts: 2,561
Likes: 1
From: Earth
I built my exhuast system using an assortment of bends and straight tubing. I went with 2.5" tubing, a crossover and dual Flowtech Terminators 
I wouldn't use the flexible tubing. If you just get a few assorted bends, it will work just as easy and you won't have to worry about leaks. You can only bend that "flexible" tubing so far. 
I wouldn't use the flexible tubing. If you just get a few assorted bends, it will work just as easy and you won't have to worry about leaks. You can only bend that "flexible" tubing so far.
Post Fiend
Joined: Sep 2004
Posts: 5,231
Likes: 1
From: Near Fresno, California
Thanks Tim, you have shown me something I didn't know about. The flex tubing like what Randy discribed is all that I knew - and it sucks - leaks, and burns out quick. If you do use this, please let us know how it works out.
Thread Starter
|
Senior User
Joined: Apr 2002
Posts: 414
Likes: 0
From: Austin, TX
Originally Posted by WillyB
Thanks Tim, you have shown me something I didn't know about. The flex tubing like what Randy discribed is all that I knew - and it sucks - leaks, and burns out quick. If you do use this, please let us know how it works out.
When I saw one of the ones I'm describing with a flange end it really got me to thinking how much easier it would be to do my own exhaust. I just do not have the faith that I could cobble together various prebent pieces and make it look good.
I am hoping that someone with experience in these matters will come along and give some first hand advice.
I am going to put eyeballs on this idea this weekend. Sure is intrigueing.
Trending Topics
Fleet Owner
Joined: Jul 2004
Posts: 27,294
Likes: 1,055
From: NM
The piece shown is actually a flexible connector in engineering parlance, it is used for vibration isolation and to allow some misalignment (not a lot). It really isn't intended to be permanently mounted with an angle in it, if that's what you had in mind. I think if you look inside you'll still see the corrugations Randy was talking about.
My Saturn came with one in the stock system, most FWD 4-lungers do. This is because of the torque of the mighty 1.9L engine rotating the engine on the mounts, which on a transverse engine results in a rotation relative to the rest of the exhaust system. 4-bangers also vibrate more inherently, and these help quiet them down.
The one on my Saturn has gone 157,000 miles with no problem, they are a quality product (from the OEM's anyway). But I've never seen one that wasn't installed straight in line with the rest of the system.
My Saturn came with one in the stock system, most FWD 4-lungers do. This is because of the torque of the mighty 1.9L engine rotating the engine on the mounts, which on a transverse engine results in a rotation relative to the rest of the exhaust system. 4-bangers also vibrate more inherently, and these help quiet them down.
The one on my Saturn has gone 157,000 miles with no problem, they are a quality product (from the OEM's anyway). But I've never seen one that wasn't installed straight in line with the rest of the system.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Top 10 Ford Truck Tragedies
Joe Kucinski
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
Thread Starter
|
Senior User
Joined: Apr 2002
Posts: 414
Likes: 0
From: Austin, TX
Originally Posted by ALBUQ F-1
The piece shown is actually a flexible connector in engineering parlance, it is used for vibration isolation and to allow some misalignment (not a lot). It really isn't intended to be permanently mounted with an angle in it, if that's what you had in mind. I think if you look inside you'll still see the corrugations Randy was talking about.
My Saturn came with one in the stock system, most FWD 4-lungers do. This is because of the torque of the mighty 1.9L engine rotating the engine on the mounts, which on a transverse engine results in a rotation relative to the rest of the exhaust system. 4-bangers also vibrate more inherently, and these help quiet them down.
The one on my Saturn has gone 157,000 miles with no problem, they are a quality product (from the OEM's anyway). But I've never seen one that wasn't installed straight in line with the rest of the system.
My Saturn came with one in the stock system, most FWD 4-lungers do. This is because of the torque of the mighty 1.9L engine rotating the engine on the mounts, which on a transverse engine results in a rotation relative to the rest of the exhaust system. 4-bangers also vibrate more inherently, and these help quiet them down.
The one on my Saturn has gone 157,000 miles with no problem, they are a quality product (from the OEM's anyway). But I've never seen one that wasn't installed straight in line with the rest of the system.
</O
Hotshot
Joined: Oct 2004
Posts: 15,882
Likes: 88
From: Durham NC
Originally Posted by f1fordguy
Randy
Actually I also am familiar with the flex pipe you are talking about but this stuff is major league different. Stainless woven with weld on, slip on or flange ends.
http://cgi.ebay.com/ebaymotors/2-5-x-8-Exhaust-Flex-Pipe-Tube-Stainless-Steel_W0QQitemZ8068612350QQcategoryZ33633QQrdZ1QQc mdZViewItem
I'm thinking about 2.5" tubeing.
Tim
Actually I also am familiar with the flex pipe you are talking about but this stuff is major league different. Stainless woven with weld on, slip on or flange ends.
http://cgi.ebay.com/ebaymotors/2-5-x-8-Exhaust-Flex-Pipe-Tube-Stainless-Steel_W0QQitemZ8068612350QQcategoryZ33633QQrdZ1QQc mdZViewItem
I'm thinking about 2.5" tubeing.
Tim
They run >100.00 at the parts house.
Senior User
Joined: May 2005
Posts: 102
Likes: 0
mesh pipe
I had a 198X something honda accord that had the flex pipe at just after the fire wall to help with vibrations, I went through two in about 50,000 miles. The car was not tuned well, and probably vibrated more than most, but it was not bent rather a straight shot to isolate vibrations. Cheapest I could get it replaced for was $100 almost a decade ago.
BTW, the mesh was stainless. Destruction involved a hole in the stainless mesh, that gradually got larger.
BTW, the mesh was stainless. Destruction involved a hole in the stainless mesh, that gradually got larger.
Thread
Thread Starter
Forum
Replies
Last Post
Lagniappe
Small Block V8 (221, 260, 289, 5.0/302, 5.8/351W)
7
Nov 1, 2016 09:42 PM
cwlightning03
1978 - 1996 Big Bronco
5
Oct 30, 2013 12:42 AM
