GTS exhaust gutting

Johnny,

thanks for the update. I'm going to gut them myself, but have a muffler shop do the welding and fab of the "Y" pipe since I do not have a welder.

thanks again,

John

quote:

Originally posted by JohnnyAlki:
Johnny,

thanks for the update. I'm going to gut them myself, but have a muffler shop do the welding and fab of the "Y" pipe since I do not have a welder.

thanks again,

Welders are pretty cheap now. You may be better off buying one than spending the money on paying the shop to do a one time job. Buying my welder is one of my best investments I've made. Taught myself to use it and it's done a lot of auto and home projects since.
John

Dennis,

Please tell me more. What make\model did you buy? How did you learn to use it? books, videos, friends, etc....

thanx,

John

Ron,

I used 2"OD tube for the Y piece. This is the same diameter as the holed pipe that I cut out.
The pipe going into the box is 2,3/8"OD and it reduces down to 2"OD at the entrance of the box. With a lot of work it would be possible to reconfigure it so that the 2,3/8"OD pipe continues right into the box. But this would mean you would have to make a jig to get the inlet pipe back in the right place as you would have to remove it entirely to open it out.

Johnny Alki, buy a welder you will love it. You will find yourself using it all the time and wonder how you ever managed without. Mig welding is easy to learn. You just need to watch someone else do it. My favourite is Miller, but Lincoln is also excellent. Dont buy a brand you have never heard of, it would be a waste of money. 160amp would be fine for car stuff.

Johnny

Johnny Alki,

I've got a 110v Lincoln Weld Pak 100 Mig welder. It came with an instruction video and book. I had already learned to use a mig at a community college auto body course. Mig welding is easier than gas or arc. If I was to buy again, I would step up to a 220v mig. I used a fellow Pantera owners 220v Miller and it's nice.

Dan

quote:

Originally posted by Johnny Woods:
Ron,

I used 2"OD tube for the Y piece. This is the same diameter as the holed pipe that I cut out.
The pipe going into the box is 2,3/8"OD and it reduces down to 2"OD at the entrance of the box. With a lot of work it would be possible to reconfigure it so that the 2,3/8"OD pipe continues right into the box. But this would mean you would have to make a jig to get the inlet pipe back in the right place as you would have to remove it entirely to open it out.


Johnny

Thanks!!!

OK boys and Girls... I dropped the exhaust on # 3463 this a.m. Monday it will be at my friends muffler shop for the gutting and v-diverter fix. I have elected to not do the V-pipe as I have had gutted, empty exhaust on one of my Sting Rays (from Classsic Stainless > Long out of business) and really liked the hollow & deep and free flow sound. Since I am not tracking or dynoing my car and since this is an experiment before my headers and 3" pipe to the exhaust "we'll see." Keep you all posted on the outcome...

Dave # 3463

I’ve been messing around with my ANSA mufflers too and have had some success by drilling out the baffles. Too expensive of an item for me to cut open! I don’t have access to the main pipe that has all the holes in it but it looks like it has around 320 1/8” holes. The holes could be 3/16” or larger but I cannot tell for sure. This is what I’ve done so far http://www.panteraplace.com/page200.htm

From my calculation each 1/8” hole would have an area of .0127 sq in X 320 = 4.06 sq in total open area for the center pipe and that’s a lot larger area than the inlet pipe that has 2.4 sq in on my system. Is it possible that the restriction is caused more by the limited number of holes in the baffles and not necessarily the center pipe? I realize that a total area made up of many small holes does not equal the same flow rate as one large hole of the same area.

Mike

Any thoughts on my calculations?

Mike

I've been thinking (and that's the problem) about the V-diverter (the angle iron set between the tailpipes) effectiveness. I can't see that it would really make much of a difference. As the pulse comes out of the entry pipe, it slows down and radiates outward. However, the added pressure starts to squeeze the contents of the can out of the tailpipes way before the pulse reaches the tailpipes. Furthermore, the tailpipes are not that big since they have that fiberglass stuff in them, maybe an inch in diameter. So the expanding pulse would not really got through them cleanly anyway. In fact the pulse would cause a lot of turbulence by the tailpipes restricting it even more.

Besides, wouldn't torque be better with a little back pressure?

Interesting ideas Jeff. The exit pipes are about 1.45 each for a total area of 3.302 sq. in. combined. The standard ANSA has a 2.405 sq. in. inlet and the GTS is about 3.14.

Mike

My 2 cents...

David Berman has a 540 bhp motor (engine dyno tested) that dropped exactly 20% when installed in his GT5 and measured on a chassis dyno. This is pretty typical of every Pantera I have ever read of that has data for both the chassis dyno & engine dyno (19% to be exact).

David's exhaust system includes the stock GTS/GT5/GT5-S mufflers. I am confident in writing that these mufflers "unmodified" inhibit performance no worse than any muffler for a 550 bhp or less motor.

cowboy from hell

The exhausts I modified in this post now emit 112dB at 3000 RPM. My friend recently had it tested at Goodwood circuit.
A few years ago I had my car tested (with the factory group 3 exhausts) and found it to be exactly the same 112dB. So it would seem having all the holes in the Y piece makes no difference to the volume at all. I certainly wouldn't want it any quieter.

Johnny

Interesting! I kind of thought that with the center inlet pipe with all the holes having 4.06 sq. in. of open area that it would not be muffling anything and might not be restricting the flow very much. For those that do not want to cut open the muffler adding a lot of holes in the front and back baffle could be an easy solution. If loud equates to free flowing exhaust, then I’m making good progress!

Mike

Are there any flow dynamics engineers following our forum that know how to calculate flow restriction in a perforated pipe? I’ve been researching how flow is calculated through perforated pipes and it is really complicated including the impact of the hole size on the Reynolds numbers! I’m trying to calculate the flow restriction on the main perforated pipe.

My latest modification effort can be seen at that bottom of this page http://www.panteraplace.com/page200.htm

Mike