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· Senior Contributor
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Discussion Starter · #1 ·
Since I am soooo... Terrible at remembering names I can't remember who showed me their custom monza exhaust at Carlisle. Someone was going to send me the complete part list of the items he used to fabricate this sweet system. If you are out there I would appreciate the info.
Thanks in advance.
 

· Senior Contributor
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Discussion Starter · #3 ·
I believe so, I know it had a 2"+ custom bent pipe over the rear axel and a small monza (like 11") muffler in the middle, it had two chrome tips out the back with a yellow ring at the rear of the tips, which is the way they come from monza I guess.
 

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Monza Tips

Jeff,
I think you thinking of my red 73 GT at Carlisle. I had replaced the exhaust system with 2" pipes except over the rear axle where I ran 2 1/4" pipes. Just send me a private message and I'll send you the parts list I used.
Brian Quick is the one who gave me all the help and parts I needed so I am more than willing to help others who would like to convert to this system.
 

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Roy and his 73 GT will be at my house today. We are changing out all the rubber bushings in the rear suspension so I'll take photos of the exhaust system and post them along with the parts list later today.

hth
Brian
 

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Exhaust Parts

Keith,
I will post the parts list this evening after returning from our Carolina Opel Club meeting today. I will take a few pictures as well.
 

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For all those that requested the parts list from OOONER for the exhaust system on his car here it is:

Muffler - MagnaFlow part number 11365 (4 x 9 oval, 11” body with a 2” inlet center, 2 ¼” outlet
offset) (4 x 9 oval with 11” body)

Mandrel bent pipes - 2 ea SUM-622001 (2” tube, 4” radius)
2 ea SUM 622002 (2 ¼” tube, 4 ½” radius)
or
2 ea SUM 622003 (2 1/2” tube, 5” radius)

available at http://www.summitracing.com/

Exhaust tips - 2 each PaceSetter Monza Exhaust tips (we both used # 15060) 2’ inlet 3” angle
cut single outlet

available at http://www.autopn.com/autoparts/performance_exhaust/exhaust_tips.html

Misc Items -
4 foot length of 2" pipe
2 each exhaust hangers
2 each muffler clamps
2 each rubber exhaust donuts


One of the 2” mandrel bent pipes was cut and welded to form the offset just behind the stock head pipe to align the front half of the system with the muffler. We used the original piece from the stock system as a guide when we made the cuts and tacked it in place. The other one is cut in the center of the “U” and a straight piece was added to match the dimensions of the scallops in the rear panel, this is the piece the Monza tips were welded to. After the entire system was in we marked the legs of the “U” coming out the back using the Monza tips as a guide and then cut the legs back to get the tips to extend back the desired amount.

One of the 2 ¼” or 2 ½” mandrel bent pipes was cut and welded to form the over the axle section. The other one was cut and welded to the over the axle section to tie it into the muffler on one end and the previously fabricated “U” for the section going out the back.

Note: When I did my car I used 2 ½’ pipe over the axle. On OOONER’s car we used 2 ¼” pipe. We used 2 ¼” on OOONER’s car so the exhaust was not as loud and since he has a stock low compression engine we didn’t see this as hampering performance too much.

The muffler is a tight fit being a 4 x 9 oval with an 11” body but it will fit without hanging too low if you cut the stock muffler mounts off.

My recommendation for anyone that wants to replicate this is to get the tips and the muffler and take them and the photos to a good muffler shop and tell them to do it this way, unless of course you like to fabricate stuff. The reason I initially did my car the way I did was because every shop I took the car to run 2 ½” pipe the entire way and only make one tip active. So I decided to do it myself.

The next posts show the various sections and/or pieces.

hth
Brian
 

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Thanks Brian. Has anyone considered installing a flex pipe at the engine end, to cut down the vibration transmission a bit. I have seen after-market flex pieces that look like you can just weld in. But the trick might be to find one short enough that it doesn't interfere with the frame rail.
 

· boomerang opeler
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kwilford said:
Thanks Brian. Has anyone considered installing a flex pipe at the engine end, to cut down the vibration transmission a bit. I have seen after-market flex pieces that look like you can just weld in. But the trick might be to find one short enough that it doesn't interfere with the frame rail.
i use them and will post a pic tomorrow when i can see it get 1 :) they are good if you add an extra support to keep weight off the flex pipe
 

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Roy came to Atlanta to look at how mine was set up and that's what he did. Although I sourced all my stuff through MIDAS, it can be done with most any parts house pieces.
 

· Pathologic Opeler
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my efforts failed on the flexpipe

here is a short 2 in dia piece of flex pipe, when my 2 in exhaust was done last year, i brought in the piece and the shop said they couldnt put it in.

a 2in diameter has a 3in external,and the way my y pipe exits ,it appears they are correct.

PS:i saw oooners exhaust at carlise, i like it much better than mine,i like how the pipes exit, there is no big gaps by the bumpers
 

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· Senior Contributor
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Discussion Starter · #19 ·
Thanks to everyone especially Oooner and bq97 for their input - ask a question here and you get the very best of answers - :D
 

· 1971 GT
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I was reviewing this thread prior to putting a new exhaust in my GT. I looked at the Magnaflow site and they have a muffler listed that is 3 1/2" x 7" (11132). This is smaller than the one used in this thread.

For those of you who have done this, would they in/out offset on this muffler cause a problem?
 

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