Exhaust question - offset or central position?

Hi everybody

I`d like to ask something you concerning the 2.5" exhaust system from TA for my 1971 Buick GS455.

I bought the tail pipe assembly and would like to know if its made for an offset muffler or a central positioned one? Or can I use both?

Maybe someone can give me a hint? All help and opinions appreciated.

Jens

 

I’ve always used offset/offset mufflers on my 350 GS

 

Yes! Offset/Offset for a Skylark. Originally I had Center/Offset and I had to angle the mufflers to keep them from hitting the driveshaft. It drove me crazy till it was fixed.
Cliff

 

The proper tail pipes and mufflers should look like this .
Note how the inlet and outlet are offset on the tailpipe.

 

Offset for sure.

 

Everybody...really, what would I do without your knowledge? Thanks for your fast help...so, offset for sure.

All the best

Jens

 

I have a set of offset offset for my 66 and have figured out that offset inlet center outlet is the ideal muffler in order to accommodate the bigger tailpipes. The offset outlet makes it very difficult to use the brace that ties the upper and lower control arm mounting points together

 

x2 - I use the dynomax 17748's on the 65, the 2.5 " pipe needs more room that an offset outlet can provide. I also use the center outlet Vibrant 1106's on my 71. An offset outlet MIGHT work, but it would be super tight.

 

The Dynomax 17748 have a center inlet and offset outlet. Is that what you used?
https://www.dynomax.com/super-turbo-centered-offset-641.html

 

Those muffler can be used either way. Offset inlet/Center outlet.

 

Interesting side note. I had a pair of 10-year-old new in the box 17749s that I determined were not ideal so I ordered a new set of 17748 that arrived yesterday. New mufflers are dimensionally the same as the old mufflers with the exception of the center outlet versus offset outlet. The new mufflers are each 4 lb lighter than the old mufflers and there's a definite difference in the quality of the crimping in the new mufflers

 

I also have the Walker 17748 offset inlet and center outlet muffs on my MagnaFlow 2 1/2 system and they fit fine.

 

The new 17748's I received appear to have very little if any fiberglass packing in them. They sound hollow when tapping on the case with a knuckle. The 17749 sounds solid.

 

So you saying the quality is not as good as the 17749? Not surprised at all.

 

What about anybody’s experience with 3 inch system?

Offset/offset or offset/center ?

 

As I recall wih the 3" i had to go center out

 

You can make a lot of stuff fit, but generally speaking, and offset inlet toward the driveshaft, with a center outlet gives the best fit with bigger pipes. It's actually all about where you can hang the muffler.. The two pictures on this thread, of Larry's and Ray's systems, show quite clearly the muffler position difference.. look at the space between muffler and the lower control arms..

Yes, the 2.25"/2" factory system used offset/offset, and with that small a pipe, everything fit perfectly.

JW

 

My system is T/A’s 2.5” pipe, and I was all set to buy 17749s, but T/A said use the ‘48s. I asked on here, got mixed results, and went with what T/A said. So, I have ‘offset/center’ and they fit fine. Sound good and flow well, too, just ran 106.7 mph with full exhaust and manifolds.
Patrick

 

Rays tailpipes appear to have a much broader curve where it goes over the axle compared to the TA pipes. I tried the center outlet mufflers and they didn't offer any advantage. My system was bought 10 years ago so it's possible they have changed a bit since then.