C3 dual exhaust center bracket -shape?

[Gordon D.]

I'm changing a 1979 L48 automatic from single to dual exhaust, 2 1/2 inch diameter. I've seen two different center support brackets. One looks like an elongated "u" - symmetrical shape. The other is non symmetrical in shape. Both have been described as "correct". Since my original setup is single exhaust, I have nothing to use as a master. Please help.

[Gerry Proctor]

Re: C3 dual exhaust center bracket -shape?

Which one is correct, from a modification persepective, depends on the transmission. The asymetrical bracket is for automatic transmissions and bolts to the transmission tailshaft housing. The other bracket is for manual transmissions and I believe bolts to the trans mount. It should be pretty clear on this in the catalogs, at least the ones I've seen.

[Gordon D.]

Re: C3 dual exhaust center bracket -shape?

Thanks, Gerry. I too saw the catalog descriptions, but a tech expert at one source said I needed the "manual" part for my automatic. Perhaps I confused him during our discussion. I will order the right part. I really appreciate the knowledge shared by NCRS members

[Joe L.]

Re: C3 dual exhaust center bracket -shape?

Gordon-----

I don't know if there is a bracket that will work as-is for your application. GM never produced a THM-350 with dual, 2-1/2" exhaust. So, there is no bracket that I know of that will, for sure, work as-is.