Re: Putting 4000 quattro manifold on '85 Coupe GT?

["Bruce Bell" <bbell@bbell.com>]

> then the downpipe brings them together into one 2-1/4" or
so
> outlet.  

Actually it is closer to  2.5" and so is the cat on a 4Kq.
the rest of the exhaust is 2.25" from the cat back.
 
> > Am I correct in thinking that the manifold will drop
right in, but using
> > both the manifold AND downpipe from a 4000 would
require me to modify my
> > stock exhaust on my Coupe?
> 
> No, you must use both.  You'll need (5) new exhaust
manifold/head
> gaskets and a new manifold/downpipe gasket. 

> The early 5kt cat is the right diameter
> or you can get a new one.  You need to install the OXS in
the pre-cat
> connector pipe also, since the stock one is in the
manifold.  Use a
> heated OXS since it's a lot further from the heat of the
head.

Not sure about the 5kt cat, but the 4Kq cat has the oxy
sensor fitting at the cat input side.

Don't think the swap is worth it unless you upgrade the cat
back to at least 2.25"

Bruce