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1970 Dodge Dart - Vintage car valve seats?

How do you know if your vintage car needs valve seats?

Brand spanking new or vintage car; the procedure for diagnosing bad valve seats is the same.

You run a dry and then wet compression test on all cylinders. If both the wet and dry test shows low compression in that cylinder, the valve seats are likely not sealing.

A leakdown test will also show bad valve seats but you need to listen at the exhaust and intake for the “hiss” of leaking valves.

If your engine is running smoothly and easy to start, you don’t need valve seats. If you are worried about unleaded gas, I used to run Amoco High Test unleaded in the 60s all the time and it had no lead. There are also lead substitutes in a bottle. Unless you are using this as a daily driver I wouldn’t worry about it.

Thanks, I think I am good. The old Dart Swinger was turning a 14.85 in the quarter last time I had it to Cecil County Dragway. She’s fun in the quarter mile, but with no roll bars is more than a handful in the corners when driving any distance. Really considering adding them just to make it safer and more pleasurable to drive.

I don’t know if they’re still available, but I added a front aftermarket anti-roll bar to my '72 Duster years ago.

Turns out Summit has Addco kits (along with other brands) for your Dart. I’m pretty sure it was an Addco that I put on my Duster.

Thanks, I’ll look into it. It just feels like it wants to roll over onto its nose if you take a corner to quickly. It has no sway bars, no power steering or brakes, but it has the one year only four piston front disk brakes and drum rear brakes. It’s a 340 cu. in., 4 speed car. I had a '71 Duster with a slant six back in the day. I was looking for a Duster when I found the '70 Dart. What does your Duster have?

I would do a rear sway bar kit too. Addco shows a kit for your Dart, but lists it as out of stock.

Oh, it’s long gone. I had it in high school, through college, then sold it a year after I started work. It had the smokin’ 198 CID slant 6 and a 3 on the floor. Slow but sturdy, I pulled a small U-Haul with it from TX to CA and back.

I thought that the front stabilizer bar was standard equipment on 340 cars, do your lower control arms have the mounts for the stabilizer links? The 6 cylinder cars didn’t have the mounts on the lower control arms for the stabilizer bar but those are included in the Addco kit.