Foretravel Owners' Forum For owners and Fans of Foretravel Motorcoaches September 19, 2025 ...

In the early 60's when I was racing a 348 and later a 409 in the stock class we would brake a new exhaust manifold in less than a month, my father asked if I was tired of keeping Chevy afloat and said we could cure that problem, the next manifold was heat treated in a pit in the yard with 25 pounds of charcoal, we took a piece of half inch stock drilled it to match the new manifold bolted to it placed it in the pit with the now hot coals and covered it with coals and dirt, left it until the next day,took it out hung it from the cloths line pole and let it cool for 2 days, the long and short of it was I never had another on crack or break a bolt.

I am replacing my exhaust manifold next week and wonder if you think that I should heat treat it as you said....would you do that to yours if it needed replaced? Did you bolt the manifold to a thick piece of lumber before " charcoaling " it? I would worry about warping and twisting.
thanks Pat

Pat, I can't say it will work with the cast iron we have today.

Ugh, found both bolts missing on exhaust port nearest  rear of motor/ front of coach. Manifold appears to be obviously warped. My hope is that as the manifold has shrunk down it has also bound in on both ends minimizing potential damage to the head from cold air sucking in on deceleration. Any ideas on where to find an improved manifold or is OEM as good as it gets?

I don't think that I would take it on the trip until the manifold has been replaced though.

and one of them being fitted with a bolt and nut solution

There is no improved part from what I found when I replaced mine. 

If you are in a hurry to get this done, I'd just take it to Cummins and let them worry about it, especially since some of the bolts are broken.  It might cost an arm and a leg though. 

I don't think that I would take it on the trip until the manifold has been replaced though.

If anyone knows why we can't simply ream out the upper two and add nuts and washers I would definately be curious the lower two are going to have to come out and or be tapped one way or the other.

Its a 1 or 2 thousand mile deal for us. I took your advise to heart and will remove the thermostat/coolant filter assy. in coming months then install Helicoil or similar at nut and bolt and one other hole we re threaded. Old Trucker said the boost gauge is best tool for detecting any leaks before any scorching can occur. At this point the fact we didn't outright break the head is a victory  from my perspective. Fired right up, no clacking nor visual evidence of any leaks.
 Also pleased that head showed no signs of scorching from previous bolt issues. The fact remains that having traveled untold thousands of miles with two broken bolts at same port without damage is a true blessing.
                                                  Thanks for all your responses.