Does anyone know of an off the shelf dual exhaust kit for an old style 90' caprice? I want to keep my 9C1 nice and quiet keeping the stock manifolds. Everything else is stock so maybe even a "high performance" single system would do? Thanks.

I'm not sure that an off the shelf dual exhaust system is available anymore fot the older style Caprice's. What I did for my car is bought another set of stock pipes, muffler, and catylitic converter (junk yard), and cut up the pipes, and re-welded them backwards. Then I cut up my crossover, and made it onto two individual pipes coming down from the engine, and put it all together to make a true dual exhaust. It seems like a lot of work, but it wasn't all that bad. A couple hour job with a welder.

I've been doing some looking for that exact same issue. I have a '90 9c1 and I wanted to know if I could find a dual exhaust kit. My current research and knowledge of 9c1 caprice history has lead to the conclusion that dual exhaust kits (full kits, not just parts here and there) are only available for '94 and later year caprices because these were already designed for dual exhaust (5.7L came with optional factory installed dual exhaust). Anything before '94 requires a custom job like PeteA216 did. I repeat, my current understanding is that no dual exhaust kits are available for any model year before '94.

HLandin is correct. But, the kits that exist for the 94-96 cars can be adapted....

Using a set of factory LT1 manifolds on your 90 will allow you to use the complete exhaust system from the 94-96 cars.....

Awesome! do you know if I can disable the air injection? Does it affect performance? I'd like to do away with it if possible. Thanks.


HLandin is correct. But, the kits that exist for the 94-96 cars can be adapted....

Using a set of factory LT1 manifolds on your 90 will allow you to use the complete exhaust system from the 94-96 cars.....

Yes you can. There are plugs available to fill the exhaust manifold ports. There is even a bracket with a pulley available to replace the AIR pump.