Here to pick somebody's brain. I have a 1985 GS that needed an exhaust so I pulled one from a 1983 GS L part car that I have unfortunately the exhaust(downpipe to Muffler) is too short. Would swapping the exhaust manifold solve this problem? Or is there another answer that I'm just not seeing?

 

The (stock) manifolds are the same. Are you missing a CAT? Or the connecting pipe with the hangers on it?

 

No I'm not missing anything and the exhaust fit the 83 gsl perfectly not problems. When I put the down pipe on the angle is wrong and is too short.

 

if you think swapping the manifolds will work, then why not? you have the parts right there.

it does sound odd though. i always thought the manifolds on the '83s were the same as the S3 12A cars.

 

Yeah, there's only 2 manifold types: The Thermal Reactor from the SA and then the Manifold on all the FB's.

 

There are actually 2 different FB manifolds. The one in the picture above is more or less 84-85. The more-or-less 81-83 is similar, but the exit is longer and slightly different angle. The early one was preferred from a flow perspective for Spec7's. I have both sitting around somewhere.

Carl

Early FB

Late FB

 

Thank you Carl, I never knew.

 

i had always suspected there were two different ones, but i thought the breakdown was 1981-82, then 1983-85. so i thank you for that tidbit as well.

 

Looking at the diagrams in the parts manual, it appears that they shortened the manifold in 84 to make room for the third catalytic converter.

Carl