Test pipe for 78 Trans Am
 

Anyone still make them? The cat on my 78 is clogged and turning into a meteorite, and since I dont live in an emission state, a test pipe would be perfect.

I can make my own, but I see Gardener and Waldron offer them if you buy their systems. Since I already have a system, I'd just like the pipe, but cant find anyone selling it individually.

Anyone know where to locate one, or want to sell me one? Worst case I can make my own, but figured I try this route first.

https://forums.maxperformanceinc.com...highlight=Test

Maybe he still has it.

You can make your own, if you can weld exhaust pipe, but anyone selling one could be liable for a rather hefty fine. Right now the EPA has cracked down hard on the Diesel Brothers, and some other guys that have You Tube channels for modifying their emissions systems. I think the Diesel Brothers were fined $850,000.

I had a friend that owned a Midas franchise, and used to make them up, but the threat of the EPA busting anyone making test pipes scared him away from continuing to make them. This was in the 80s, not recently. This was the time the test tubes went away, and disappeared.

The other avenue is to change the early 2 hole flange on pre 74 headpipes to a 3 hole flange so they can be bolted to the later manifolds, then retrofit an early dual system to the later chassis.

The old convertor can be gutted, and empty the pellets out too. You have to be able to weld the plug back in though. I've probably known of these ways around the catalyst since the 70s, I would never do them though.....:eek: ;)

I can make one, but figured I'd see if anyone had one first. I've gutted plenty of modern cats, but never a pellet style. How bad are they to gut?

I've heard that, once you remove the plug, the pellets can be taken out, then there is a baffle under the plug that can be reached with a air chisel, or cutting torch to punch a hole through it to allow better flow. That baffle is used to redirect exhaust flow. Then you need to straighten the plug out, and weld it back in to the body. It looks legal, but nothing in there to obstruct flow.

I've heard this, never have done it, of course, because of the legal ramifications....;)

Ahh but of course, we're simply discussing semantics.

I'll investigate it tomorrow and see what I come up with.

Pull it sell it for scrap, buy some beer install your own pipe.

Bam.
( for testing only, or off road use, not for use in the state of California, these parts have been known to cause cancer to Dem’s )

I think I got mine from JC Whitney!

The good ole days! :)

Test pipe ... lol. I rember those from the early catalytic convertor days. Scouts Honor, I'm only gonna' run it long enough to see if the convertor is clogged. Honest. I think they eventually changed the name to "off-road pipe for competition use only".

I recall sometime in the past year that a forum member posted here that his exhaust was so stinky he ws putting on some universal cats.
Seems to me that he would have to modify his tune so that the cats would not overheat. Can't remember who it was but maybe he would swap his stinky exhaust system for your system with the cat:D

The whole point of GM's pellet-style catalysts was that defective/worn-out catalyst pellets could be replaced with fresh ones using a vacuum system the Stealership would have as a "special tool".

Should be able to open the Cat, and dump the pellets out. Assuming, of course, that the threaded plugs haven't seized in the decades since they were new; and the mesh inside the cat was still intact.

When vehicles with pellet-style cats came into the shop, we'd smack the muffler with our fist. A large proportion of them rattled like Maracas 'cause they had a heap of catalyst pellets in them. Wasn't unusual to see cars idling at stop lights, spitting pellets out of the tailpipe. When the mesh of the catalyst tore or rusted-through, the beads would migrate downstream.

Those were the worst exhaust systems, put some HO’s on and a dual exhaust.

I've had a lot of tire kickers on mine so i finally gave into ebay. it's listed if you want to bid.

https://www.ebay.com/itm/255962738143

I don’t see the listing 🤔

I dont see it.

The auction got pulled and guess why.

Used catalytic converters are not legal for resale.

Neither are "Test pipes".

The test pipe I have identifies as a Cat.