I am going to change my Olds over to dual exhaust and was hoping for a little advice. I am getting the correct "S" driver's side manifold Thornton reproductions and am debating if I should also change the passenger side manifold as well. I could just go with a block off plate to save some money but wonder if it would work better with a new dual exhaust manifold. I did have the manifolds planed when I had them off over the winter so that is not an issue. If I do put on new manifolds then I am taking to a shop about 5 miles from here to have the exhaust installed. should I have the car towed or trailered there? Other than being really loud will running it from here to there hurt anything?

 

The block off plate is what the factory did and it is fine. The only manifolds without the block off would be a 442 manifold or Toronado rt side manifold. It would be your choice as what to use. As for driving with just the manifolds on I am not sure its a good idea (reasoning am not sure of) and surely you would have to make certain that the hot exhaust does not damage anything underhood.

 

If you are going to drive it to the location you need to at least install a temporary pipe that directs the exhaust flow under the car. I have seen many underhood componants melted by people letting the exhaust exit under the hood. Not to mention the amount of fumes you would be getting inside the car.

 

I had dual exhaust installed on my 71 98 after I installed the engine with new W and Z manifolds. I put some pipe and muffler clamps on as a temporary fix when I started the engine the first time. I ended up having it towed 5 miles to the local exhaust shop becuase my insurance has free towing. I didn't know about melting under hood components. I'm glad I didn't risk it. It was only started without exhaust to move the car from the parking lot into the exhaust shop.

FWIW, I suggest having your passenger's side manifold welded closed. This will look better than a block off plate IMHO and it won't leak when the gasket gets old.

 

There are no gaskets on that surface.

 

It seems that I remember (from way back) that if you ran w/the exhaust exiting quickly, as you are considering, there was a danger of burnt exhaust valves. Think I would tow/put her on a trailer.

 

I'll have it towed. The car has single exhaust now and a crossover pipe to the other exhaust manifold. That is where I was wondering about welding on a Block off plate or Hunk of metal to cover the hole! Or would you think that getting both the W & Z manifolds for duel exhaust is better for some reason. svnt442 what gaskets are you talking about? I did not mention gaskets.

 

You didn't, but Olds64 did.

With a big block the W/Z manifolds would be the way to go if you have the cash. But it would depend on your budget and what you want to do with the car.

 

Reminder- W & Z do not work on 65-70 B/C car. You need S & T manifolds.

W & Z will work fine on a 71-76 though!

 

If you take the passenger's side manifold to a good welding shop they should be able to weld a plug into the crossover flange.

Oldsguy and I had some welding done on the exhaust manfiolds of his 1969 Olds Delta 88. It cost about $100 to have his passenger's side manifold crossover welded closed, and to have the exit flange on his driver's side manifold welded back on. We cut the back of a driver's side Toronado manifold off and had it welded on 180* rotated so it would clear the steering on his 1969 Delta 88. It was alot of work, but at the time we didn't know about the S & T manifolds. Plus, it ended up being cheaper. $100 for labor, an hour with a hacksaw in the garage, and about $20 for the Toronado manifold.

 

Right they were advertising the "S" type for the driver's side , so the other is a "T" type?

 

The S manifold is the only one that will work on the left side. For the right hand side you have options although a muffler shop will need to make the correct bends for the pipe depending on what manifold you choose.