[Poncho Walt]

I am looking for an original style exhaust system for my 71 T/A that would use 2 1/2" head pipes that go back to the cross-flow muffler and then if possible continue with 2 1/2" for the tail pipes.. I think there may not be enough room for the 2 1/2" tails. I would then use the oversized chrome tips. I would like to have the system made of stainless but not polished. I wanted to use the Magnaflow #12468 muffler. I dont know if anybody has done this before or knows where I might be able to buy this type of system. Any leads would be great.

Thanks.

[GRNMTGOAT]

Maybe check Gardner exhausts, not cheap ,but nice fit. Bruce.

[RicksGTO]

might also speak to Waldron's Exhaust. He has a couple of cross-flow muffler options for better flow or might be able to make one to work with your choice of the Magnaflow as well. Last time I checked they would do 2.25" or 2.50" with factory bends and flat areas to mimic the original pipes. Here's their base stainless set up:
http://waldronexhaust.com/cart/index...oducts_id=4656

[whitebird400]

Hi! I installed and lots of room for 2 1/2" tailpipe! Just make sure they are firmly mounted in place. Actually I have seen 3" tailpipes on a bird!

[RAIVJUMB]

take a look at Pypes, I believe they offer exactly what you are looking for. I have one of theirs on my car and I really like it.

[Formulabruce]

Originally Posted by GRNMTGOAT

Maybe check Gardner exhausts, not cheap ,but nice fit. Bruce.

/\ NO MODS, Goes on just like the replacements I used to put on at the dealership.. Factory fit. Gardner works with the bigger outlet R/A manifolds as well.
I like the pypes, but I hate cutting and modifying pipes...

[eaglesan13]

I used the 2.5 inch PYPES system with the X-pipe and RacePro transverse muffler on my 70 Formula 400. I loved the sound and the performance (mild built 455), but the system did not fit well and required about 3 hours labor from a professional muffler shop to install it. Even at that, the system did not fit well. I think that due to the oversized pipes, the bends were not as "crisp," especially near the fuel tank.

['ol Pinion head]

Desiring the best flowing head pipes with close to stock look (flat spots for crossmember clearance) would look at purchasing or building your own reproductions of the '74-74 SD head pipes. What Pontiac did is used a mandrel bent curved section dropping from the exhaust manifolds welded into 2.5" aluminized pipe. This eliminates the narrowing in the tight bend coming down from the manifolds & the headpipe sits up high. If one looks at original '70-72 RA-T/A head pipes, '73-74 SD headpipes, & '73-74 F 4 bbl head pipes, believe all of them have flat spots for clearance below the trans crossmember. Have fabricated shortie headpipes for one of my '71 HO A bodys using the first bend made from J bend mandrel bent tubing, luckily, no need for flat spots on the A body head pipes.

[Poncho Walt]

Thanks for all of the responses. I am considering a system from The P****P**** that is offering a 74 SD system but is steel not stainless. The head pipes are 2.5" and the tails are 2.25". Price is reasonable and has the factory look. Might change out the muffler based on what it sounds like. I am still up in the air. The Gardner is way to much money. The Pypes system is not factory with the X pipe. Waldron wont make it any larger then 2.25". Still looking but running out of options.

[notime]

Call Waldrons. Ask for the loud version of the imposter muffler

[Norwood]

I used this 2.5 dynomax system along with Pypes 2.5 down pipes . Sounds great, fit great http://www.jegs.com/i/Dynomax/289/89...FdgOgQod_j0Plg

[Norwood]

https://m.youtube.com/watch?v=T10N0u31gl8

[njsteve]

Here's the videos of the install of the Pypes system and their new ram air manifolds on my Gramma's '75 Esprit (with a '71 455 with the original 6X-4 350 heads on it).

Go to 2:06 to hear how it sounds. :-)

https://www.youtube.com/watch?v=LEzDmlCyA14&app=desktop


And the thread: http://forums.maxperformanceinc.com/...gramma&page=13

[ta-kid]

I have installed both 2.5 inch all the way and also done a 3 inch on my old 74 T/A, both made in my Garage, so custom made and welded by me. Used Flowmaster crossflow and dual mufflers under the rear floor pan on two 71 T/A,s.All Mandrel bends.The 2.5 inch was not an issue for fit once you get the proper bends for the tails.The 3 inch is a challenge with the over the axle bends and 90 degree turns into a crossflow muffler.Not a lot more power if any,just more noise,but maybe that's what you want.
If you are looking for more HP power over stock pipes you only need the 2.5 inch to the mufflers.Going to 2.25 or even 2 inch tails you will not even notice the difference for a street car.There was an article in a old Pontiac mag years ago that tail pipe size made no or much difference,but a proper 2.5 with max verticle drop and then a smooth mandrel bend right off the ram air manifolds produced the most improvement.
With my 3 inch system was always under the car adjusting for rattles and knocks.