Exhaust?

[69shortcst]

I starting on my swap, a 1999 4.8 and 4L60E into my 69 cst. I've got several questions I would appreciate help with. First what mounts work best for the motor. Also for the tranny, would I be better off getting a whole new crossmember or modding mine (no problems doing the cutting or welding, just want to get it in the right location). My third question is the exhaust. Will the stock exhaust manifolds fit without having to notch the frame. I'm looking for ecomony at the end of the build so I want to keep the motor as efficient as possible. Thanks for any answers you may have.

[SamMargritz00]

if i remember right we made our own motor mounts, modded the original crossmember, and the stock truck manifolds wouldn't fit in between the frame rails so we had to get some off a same year camaro. with yours being a 4.8 and mine a 5.3 they could be different sizes and my info may not apply.

[69shortcst]

Thanks for the reply. I'll keep my eyes open for the camaro manifolds.

[Indian113]

The 4.8,5.3 and 6.0 all use the same size exhaust. I bought some 98-99 camaro exhaust manifolds for my S10. We haven't got it to the point of exhaust yet.

[mooseknuckles]

here's what I used...trans dapt ls mounts, poly mounts, and trans dapt universal crossmember, that I modified a little....

[clinebarger]

A stock 69 auto crossmember works fine with NO mods, Just use a TH350/TH400 trans mount. Slide the crossmember back & drill new holes in the frame

[69shortcst]

I just ordered and received the transdapt motor mounts but they didn't work with my frame brackets, so I'm now waiting on brackets from pol, they should be here this week. The brackets were for the big block I was running, I guess they're different. Will try to get it sitting in the frame this weekend. Then hopefully off to body.

[69shortcst]

Does the height work out with the stock crossmember? If it is just a matter of a few new holes that seems pretty simple.

[mcmlxix]

Trailblazer with the optional 5.3L or the Trailblazer SS with the 6.0L had exhaust manifolds that everyone seem to like and fit well...