318 exhaust manifolds on a 360

Tried to access the FABO last night after 8:45 and for some reason it would not come up. So I had to wait until this morning to tell everyone that "RRR" was correct (more or less) about the manifold. I had said that you could not buy the manifold I was selling from anyone except me. But that's because I modified the 53009376 casting so that it almost perfectly matches the 340 manifold with respect to the exit hole. The 9376 manifold (and all the magnum/Grand Cherokee manifolds I've checked) come with a 2 1/8" hole. The hole size varies a little between 2 1/8" and a little less. The one you buy from the junk yard may vary but I've never seen one that was 2 1/4" unmodified.
All you need to make one of your own is a manifold (which you can leave as the factory cast it) or you can modify it like I did so that it flows more consistent with the 340 manifold. We all try to get the exhaust as close to the same on both sides so you get equal output from both banks.
You'll have to buy: (If you don't already have one)
- a Carbide burr ($12-$25)
- a compressor ($150 or more)
- a die grinder ( $50 (electric) at Harbor Frieght unless you use a pneumatic die grinder)
- You can use a hand drill instead of a die grinder but you'll likely ruin the drill because all hand drills come with axial bearings which are designed to take pressure "straight on" like when you're drilling a hole. Die grinders come with radial bearing which are designed to handle "sideways' pressure.
- a sand blaster (unless you already own one or just pay $10, like me, to clean the manifold before painting)
- rotary sanding drums and the rotary sanding drum sandpaper ($10 -$15)
- an hour or two of careful cutting of the exit hole and the areas leading to the exit hole.

So unless you have all the tools and the expertise to use them you can have the same manifold I'm selling. I measure and visually check the manifold and remove all the excess material from areas that are out of round and all casting flaws (flashing, casting seams, etc). You have to do it very carefully so you don't destroy/damage the manifold. I also have an extra long carbide burr (this would cost extra unless you already own one) to reach deep into the manifold to smooth the approach to the exit hole. I'm basically porting the manifold. I know many of you have ported your own heads so you might have all the stuff you need. But just like everything else sold in the "For sale"" section, you can do it yourself or buy it already finished so you don't have to spend money on tools that you will seldom use.
If you don't already own the tools and you can't borrow them from a friend the you'll have to spend around $125 -$175 to buy the manifold and the tools. Or you can let me do all the work and take the time to make one for you. You can also use the manifold as it was cast.
I buy the correct manifold, pay $10 for the sand blasting, buy the high heat paint and I have already bought all the tools. I'm a machinist so I have thousands of hours of experience grinding and machining all types of metals. I guarantee the manifold to work as advertised and to be as close as to the 340 manifold as possible.
The one you see in my previous posts is already sold and paid for I have two more in the works. If I don't get any more requests I'll simply stop making them.
So you can spend $100 (or more) of your own money or buy one from me for $105 plus shipping. I will put these up for sale in the "mechanical parts for sale" section but since the OP was asking about a solution for his car I thought it might help if I talked about it here. Also, I don't have that many in stock so I didn't want to advertise for sale yet.
The hint that I alluded earlier was the pic of the exit hole (where it can be clearly seen that the hole has been modified (if I really wanted to hide what I was doing I wouldn't have posted that pic). Stock manifolds are never smooth and clean on the inside.


There's a lot more info on these manifolds but I have to take my little girl to school so I'll post more later today. The pic I just posted is my '69 Barracuda manifold next to the modified manifold....I know which one I want on my car!!!!!!!
Treblig