Ok, so I may have found a parts car regarding the exhaust for my '89 RS. To recap:

What I have

'89 RS, 305 5.0 V8, engine code E

Possible parts car:

'82 Berlinetta, 305 V8, engine code H


Long story short, the P.O. of my '89 decided it would be a good idea to rip out the exhaust, and custom bend two pipes, coming right off the bottom of the manifolds, one out each side, just behind the doors. While it sounds "cool" to an extent, I also get a lot of backfires not to mention the exhause echos off anything I drive by and right back into my ear through the window (closed or not)....i.e. It's really loud and almost uncomfortable to drive the car on a regular basis.

Now I realize I can go the route of replacing the exhaust, one component at a time, and lord knows there are TONS of options out there. For the time being, I'm on a budge crunch, and pulling an existing system out of a "parts car" would be cheaper.

My quest then is this, will the exhaust, namely the y-pipe direct fit from the '82 305 (4bbl, etc..) to the '89 305? Looking at exahust layouts, the y-pipe seems to be the only year specific part...the rest should be a direct fit....so what is different (spec wise, deminsion wise, etc) or otherwise put why WON'T it fit if it doesn't work?

For sizing, check post #4 below:

JamesC

# 4 bellow? Bellow what? Is there perhaps a missing link?

Crap. Here's the missing link:

https://www.thirdgen.org/forums/exha...-question.html

JamesC

Thanks for the link....

So if I'm reading the sizing correctly, the '82, vin code H, and the '89 vin code E have the same manifold, and as such the exhaust from the '82 should swap with the '89?

Or am I misreading or otherwise misunderstanding ?

Since both the H and E vin have the same 2" outlet manifolds and 2 1/4" y-pipe, I wouldn't know why they wouldn't swap.

JamesC

Sounds good to me...I'll let you know if it ends up working out!

New Update....

I started the process of pulling whatever you want to call the two straight pipes...maybe "madkeyougodeaf's" ... and ran into what might be a question...

The exahust pipe coming off the passenger side of the engine, and currently running down the passenger side, out the side, also has, what I think is an air tube (haven't done a lot of exhaust work) that also comes from the passenger side of the engine, and it is welded into the "new" pipe...This weld is right about where the Cat Converter is supposed to be (which is why I believe it's the air tube...

I also crawled under the "donor" car ('82) and it's cat converter/engine DOES NOT have this air tube....

Is this going to cause a problem, or is there something that can be done to "bypass"...or whatever!

Open to thoughts and suggestions...thanks!

Yeah, that A.I.R. tube used to go to the catalytic converter. To make it 100% correct, you would need to get a correct cat that uses the air tube.

You can hook it up to blow the air into the cat, as was factory, but the proper cat has the tube usually going to the center of the cat and then it blows extra air inside to help super heat the converter, supposedly to make it function better.

You might get into trouble if you just eliminate the air pump system, you might not. Obviously you didn't have strict smog inspection laws before this or that 89 would not have passed, hahahahha.

Does your 82 have an air pump? where do the tubes go? Maybe you could just use the 82's smog pump routing and make it the same to match what you have?

That also would not make the smog ***** happy during inspection, though, and to make it right you should use the proper A.I.R. cat.

As it turns out, even though the '82 didn't have the air tube off the engine, the Cat did....however all that being said, I ended up getting an unexpected refund (of sorts) and bought new exhaust components off line...I am now 2/3 through installing the new exhaust.

Shipping wise my new cat showed up first, and I got the y-pipe yesterday. I installed the y-pipe and cat last night, and the muffler and rest of the exhaust is due to arrive today...

One question remaining though...how are you SUPPOSED to connect the air tub on the cat to that coming from the engine? I plan, at present, on using a compression sleeve coupler, 1/2" OD (to match both tubes)...it's brass so it should hold up to the heat....thoughts?

It doesn't really matter; it should just be pressurized air from the pump, not exhaust coming back, although it will heat up.

You could sweat it on like you do water lines at the house or just mig weld it.