Just bought this 73 Barth MH, and it has an exhaust leak(s) somehwere near the manifolds. I understand this is common with the Chevy/GM 454 cid engine. I have read some possible solutions, and I was considering headers. Any suggestions that will create a more permanant solution to these exhausting problems?

Stock GM manifolds were prone to leakage. They made several changes to the factory manifolds but never seemed to get it right.

Several here (including me) have installed Thorley headers with good results. Do a search for "exhaust manifold" and "Thorley headers." There are pictures and discussions. Good luck

Here is what I posted:

https://www.barthmobile.com/eve...1087061/m/1733908187

I had a manifold leak a few years back and a friend who was a good wrench said he'd put a new gasket in, but only if he sent the mani out to be milled. An extra 50 bucks but I've had no problems since. I think the parts and labor totaled about $150, but he also removed the heat exchanger and fabbed up a replacement for it so I was happy and still am.

Danny is right.....replacing gasket without milling the manifold is very temporary. Replaced right side twice without milling, lasting a couple thousand miles each time. After milling and having studs re-torqued at 500 miles, I've gone 8 years without problem. Also, allow for an idle cool-down after a hard run. Still, headers will be installed at next gasket failure, hoping for easier breathing & better numbers.

A follow up on my exhaust leaks… I took my 73 Barth to a reputable service guy near me and, after a couple of stumbles, fixed the exhaust leaks. Turned out that one manifold was good but needed milling, and the other was cracked in three places. A previous owner tried to weld the crack but it is useless.

My service guy discovered, though, that the new manifold would not fit onto the head without milling down some factory studs that prevented the new manifold from mounting flush on the head. I'm not sure where these studs are, but the replacement manfifold was designed differently and made contact with the "studs" thus preventing it's ability to seal.

Anyway, a week and a half later, it's done and I'm ready to take our maiden voyage to the UP in Michigan.

Cool. Sounds like a good fix.

Hope your trip north works well. If you plan to be in the Traverse City/dunes area, stop by and visit if you get the chance. We are one mile from the intersection of US131 and M72. Stay in my yard or the RV park 3 houses away.

I'm not sure your timetable, I will be out of town from July 14-21 or so. (I will be boating in Lake Superior) Otherwise, stop by if you get the chance.

Thanks for the invite. We actually plan on stopping in Traverse Bay area after a trip up to Picture Rocks, Mackinac Island and down the western LP of Michigan the week of July 26 - August 2. If we get a chance to stop by, we will defintely do so.

The Old Beast is nearly ready to go. After some interior painting and repairing some plumbing issues--someone didn't winterize it, so I nearly replaced all the water lines--the 73 runs quiet, smooth and hopefully will take us the whole trip without incident.

My trip to the UP is delayed until July 21. I will be back by the 2nd for sure. If you want to stop by on the way back I should be back then. Let me know I will PM my phone # if you want. See ya.