Welcome to the nuthouse we call home. That is one GREAT looking wagon, and certainly not one I have seen in person very often, even when they were new. Looking at that picture, it would appear that you have a V-8 under the hood, with some sort of dual exhaust and a blocked up open pipe. I would give a good look at that exhaust. If there is no cross over, you are throwing away about 15 horsepower, but more importantly given the price of fuel there, about 5 mpg on the highway. The best bet is a good set of pipes, properly mandrel bent and sized according to the output of the engine. Most people go too large for proper scavenging, so lose both performance and mileage. With a stock, or almost stock, Mopar small block, you would want 2 1/4 inch pipes, no more. For a big block, unless it is seriously breathed upon, 2 1/2 is about right. Make sure you include a crossover. H pipes work, but an X pipe is better again for no up charge. I am not sure of the laws there, but if you can, have the pipes exit at the back of the car, to the side instead of below the back bumper. If you must have rear exit exhaust, borrow an idea from the old Volvo 240, and have the pipes exit as far outboard as is legal, trying to keep them outside the tailgate to minimize fumes being sucked into the car. It is much safer when you have the tailgate window open. Also, if you do cruise with the tailgate window open, make sure to add the air deflector that was optional. It also helps keep the rear window clear of dirt and water.
Welcome! Hi, Glad to see another Brit on here and with a Plymouth as well. Great looking car - it wasn't on ebay UK a while back was it? I seem to remember one very similar to it. Have fun! Rusty1
Thanks! Thanks guys for a fab welcome! Work has kept me away from the wagon for a week or so, so looking forward to playing with it over the Christmas holidays. I haven't even had time to play with the open headers! The exhaust system is fairly new, and I think may have a cross over in it already - haven't had a chance to have a look. Yes Rusty, on ebay around September time, but I couldn't get to see it - it was given as part payment for a 1958 truck, and the new owner needed the money for a new bathroom! The fact it was up for sale again was fate, so got it this time. Gerry