Mada

I got a presilencer from racingbeat for my '86 today, but don't know where to attach the tube for the 6 port actuator. If I'm not seeing it, could the previous owner have removed it? If so, would it be fine to block off? There was nothing attached to the previous exhaust system in the same spot.

Jeff76

Racing Beat makes a specific exhaust part for the 6 port hookup. Do you have this part or other?

The hookup connects to a long bent tube that connects to hoses on the engine accessories. The back pressure pushes open the 5th and 6th ports when the back pressure raises. Without this, the power loss is very noticeable.
Many years ago I was working on my exhaust and needed smokes so... I drove to the store without the exhaust. There was a very noticeable loss in power. If you hook up the hoses/pipe after not having it working and you don't notice a difference, it is time to take apart and clean the 6 port system. They just start sticking and don't open.

Many will just wire the ports open and run a normal exhaust. It has an effect in the mid-range power band if I am not mistaken. I personally wouldn't do it unless necessary. There are plenty threads here about this here and the factory service manual is very useful.

Some pics would be helpful too.

Mada

I asked the previous owner; he had replaced the stock system that works with back pressure and instead actuates it with a separate air pump

Jeff76

Nice, S5's work the same way. That is a great upgrade! I might try tackling that at some time too. If you have the exhaust part with the back prtessure hookup, you can just cap it off.

Mada

Anyone have a recommendation as to how I could cap it off? I don't have access to any kind of welder or really any fabrication tools, and I get the feeling nobody makes a block off plate for it.

Jeff76

Well then... no fab tools. If you don't want to or can't return it any muffler shop could help. I would use a thin peice of steel and cut to size with tin snips, drill the holes, add in some exhaust paste and possibly a gasket.

Alternativly, if you have an old cat with the tube and flange. Cut it off and connect the two parts together. Then either weld it shut or crimp and hammer it closed with sealer.

If you never need the outlet, the shop should just cut it off and weld a stainless patch if there aren't heat sheilds to get in the way.

I do not think taking it to a shop will be expensive at all.