6" SS EXHAUST STACK

[David Brady]

Hi Kurt,



No thanks, I already have a stock muffler. Thanks for the links,

there's some pretty nifty items there. Be careful with those fancy

braided stainless steel pieces. They look sharp, but they've always

leaked on my turbocharged subaru wrx. Kurt, you've been around

a few over-the-road coaches, Prevost' and what not, what do they

run on their exhaust systems; i.e., expansion pipes, flex pipe, etc.



David Brady

'02 LXi, NC



Kurt Horvath wrote:

David, Would you like to take that brand new muffler off my
hands???



According to DD straight pipe & ECU will not have any issues in the


95 vintage S 60.



OEM built that pipe for BB ACAP - As Cheep As Possible -



The original routing of the pipe leaves the turbo, source of the

first failure, cracked the 1st 90 degree turn a short straight run

2nd. 90 degree turn, then into a double ball connector that also

telescopes in and out. You can check out that piece of S---, sorry

engineering wonder here.



http://www.dynaflexproducts.com/downloads/DP_Catalog_03_pg70-89.pdf




Page 76 Double Ball Joint with Slip Joint Feature Allowing Lateral

Movement length 16 to 18 inches mine measures 14 .55 inches at

present. This marvel allows for 10 degrees of angularity 360 degree

rotation 2" of offset 2" axial movement,. Hell the u joints can't

move around that much. Besides it was hard clamped to the mount from

the engine in front of this connection not to mention rusted to the

point that it took an pneumatic impact chisel to get it apart.. So

what's the point. You need flex in between the turbo and the first

mount.



The Flex Connector with liner I choose is here at



http://vibrantperformance.com/catalog/product_info.php?

cPath=1022_1035_1064_1114&products_id=1008&osCsid=999d7ef5fdd15864bae3

3db41abf5ef9



The 2 90 degree turns were fabricated in that manner because it's not

easy to bend large diameter pipe in a single 180 degree bend, thus

they weld 2 90's together, which is the industry standard for

manufacturing a 180 degree turn in large pipe exhausts. Well this

ain't the factory and we're not constrained by what is easy. I have

acquired a 14ga 180 degree U-Tube that has the same external

dimensions as the original pipe. I'm not an engineer but I reasonably

certain that with the remaining 90 degree bend and a 45 degree bend

there will be sufficient back pressure.



There will also be a flexible pipe hanger mount behind the Flex

connector mounted on the ceiling of the engine compartment that will

support the middle section of pipe and will allow for any movement

and or torque that may be transferred to the pipe by the motor. The

original clamps for the muffler have to go as they are 6" but the

rubber isolated mounting bars will remain and that's all that was

there to begin with. So where's the rub? Bub!



Not to take anything away from the engineers that designed the Bird,

But there are some glaring deficiencies. 7 way trailer plug, Air

Purge System, Watts valve, Accelerator and Brake peddles, Front Left

Shock Mount, Relay for Jake Brake, W/D Vent for Slendide 2000,

Installation of Refrigerator with inadequate convection, The seat

belts mounted to floor instead of the seat, That reminds me I still

have to fix that one. Nothing like hitting a road transition just to

have the air ride seat bounce and the seat belts automatically adjust

for the slack then the air ride seat rebounds and the belts try to

cut you in half at the waist. That's just the 95 PT 42. I'm not

bitchin! I'm fixin



Kurt Horvath

95 PT 42

10AC



--- In "WanderlodgeForum%40yahoogroups.com",
David Brady "dmb993@..."

wrote:

>

> Kurt,

>

> I agree with Greg. I'm gonna keep mine stock. There's a bunch

> of vibration and movement back there. I figure BB's been building

> buses a whole lot longer than I have. Initially I'd scratch my

> head when looking at the frame and support pieces, but when

> you consider that something as big as a bus must twist and flex,

> this flexibility needs to be designed in. Make one piece stronger

> and you've created a stress raiser someplace else.

>

> I have a friend who transplanted a honda v-tech motor into a

> lotus elise. Everything worked but the alternator mount. The mount

> insists on cracking. There can be some weird harmonics and

> resonant frequencies going on that are difficult to grasp and

> only trial and error and a 50 year track record of building buses

> can solve (unless you can model it and run high powered

> computer finite element analysis on it). He's still fighting that

> mount...

>

> Okay, I'm off my soap box.

>

> David Brady

> '02 LXi, NC

>

> Gregory OConnor wrote:

> >

> > Kurt, try and figure why there were 4 bends. it may be that
it was

> > engineered to alow for swing room between the 'hung exhaust'
and

> > the 'torque reaction of the ruber mounted detroit'. look at
the

roll

> > of the torque and see that there is a place for the movement
to

twist

> > a union. I kinda think this movement was the problem with the

> > resulting crack. crack=result ;movement=cause ;facilitate
movement

> > =repair. may be that BB enginered it correct but someone

> > overtightened a band to cure an exhaust leak??????? you also
got

to

> > keep the stack from cantilivering off of the maniford with
your

new

> > design. Scavenging is one variable in fuel efficiency. even

straight

> > pipes some time will result in lower fuel economy because the


intake

> > variable get screwd. backpressure is mathed into the computer.

> >

> >

> > ----------------------------------------------------------

------

> >

> > Internal Virus Database is out-of-date.

> > Checked by AVG.

> > Version: 7.5.405 / Virus Database: 270.8.0/1715 - Release
Date:

10/9/2008 12:00 AM

> >

>

Internal Virus Database is out-of-date.

Checked by AVG. Version: 7.5.405 / Virus Database: 270.8.0/1715 - Release Date: 10/9/2008 12:00 AM