Advice/help with header install (watson)

[1991KOTH]

I hit a little bit of a roadblock with my Watson headers on the passenger side. I have removed the manifold, which has a triangular flange on the end of the manifold pipe. I had to hammer this off, but this flange wont fit on the longtube header. Keep in mind at some point in time the manifolds were switched to '95 manifolds; my car is a 91. Here is a pic.


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[Marc Haibeck]

The three bolt flange was used at the factory for '90 to '92 exhaust systems. In '93 the flange was eliminated and the connection to the exhaust manifold is a slip fit. The '91 flange was installed on your '95 manifold so that the '91 exhaust system would still fit.

With headers a roughly 10 inch long adapter pipe is needed on the right side. I believe that all of the Watson adapter pipes had a three bolt flange to connect to the exhaust system. A Jeal adapter with a three bolt flange will probably fit with a little modification. The currently available Stainless Works adapter pipe will fit except that it has a '93 - '95 style slip fit to the exhaust system. You will need to weld on a three bolt flange to fit it to the '91 exhaust system.

[1991KOTH]

Originally Posted by Marc Haibeck

The three bolt flange was used at the factory for '90 to '92 exhaust systems. In '93 the flange was eliminated and the connection to the exhaust manifold is a slip fit. The '91 flange was installed on your '95 manifold so that the '91 exhaust system would still fit.



With headers a roughly 10 inch long adapter pipe is needed on the right side. I believe that all of the Watson adapter pipes had a three bolt flange to connect to the exhaust system. A Jeal adapter with a three bolt flange will probably fit with a little modification. The currently available Stainless Works adapter pipe will fit except that it has a '93 - '95 style slip fit to the exhaust system. You will need to weld on a three bolt flange to fit it to the '91 exhaust system.

Thanks for the reply Marc! Im trying to fit a smaller tube into the header then sliding the flange onto that same tube to connect them but no one carries 2 3/4 pipe. Im wondering if I can cut that manifold pipe and use it as such.. the bend in it may complicate things though.


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[1991KOTH]

Originally Posted by Marc Haibeck

The three bolt flange was used at the factory for '90 to '92 exhaust systems. In '93 the flange was eliminated and the connection to the exhaust manifold is a slip fit. The '91 flange was installed on your '95 manifold so that the '91 exhaust system would still fit.



With headers a roughly 10 inch long adapter pipe is needed on the right side. I believe that all of the Watson adapter pipes had a three bolt flange to connect to the exhaust system. A Jeal adapter with a three bolt flange will probably fit with a little modification. The currently available Stainless Works adapter pipe will fit except that it has a '93 - '95 style slip fit to the exhaust system. You will need to weld on a three bolt flange to fit it to the '91 exhaust system.

Also; on the passenger side it looks like someone spliced the o2 sensor wire to the crankshaft sensor wire? It is very odd and im wodering if it can be a problem? The car runs fine as is.


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[Top Toy]

Auto Zone usually has 2 3/4" straight sections (around 18" long) of exhaust tubing on the shelf. Swaged on one end to slip over 2 3/4".

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[XfireZ51]

Originally Posted by 1991KOTH

Also; on the passenger side it looks like someone spliced the o2 sensor wire to the crankshaft sensor wire? It is very odd and im wodering if it can be a problem? The car runs fine as is.


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WHAT...????.?!!!!

[LGAFF]

You might be able to use a flex pipe from a local auto parts store until you can get an exhaust piece made; the crank sensor and O2 come in through the same area from the front of the car, I don't think its spliced