Congrats on the kiddo @Chris!

Personally, If it was me I'd use the BD. They are prepped for receiving the EGT probe, and they do flow more (based on what I've read). Plus they have a 3 year, 75,000 mile warranty. The fact is if your manifolds are leaking now and you plan on reusing them, you will have to take them to a machine shop to get them surfaced before reinstall ---> downtime.
Are you going to use Ti bolts (bulletproof diesel has them for $88, part number 90100043)? Cool thing about them is that they are cross drilled.

I know it's more $$ but I always think in the long run and that I don't want to do the job again, even if it means a bit more money. Just my two nickels.....

 

Thanks @zsargent !

Most of the people reusing the OEM exhaust manifolds aren't having them machined, since they typically don't warp to that extent, at least as far as I have been able to research. Using a gasket, where there previously wasn't one in the OEM setup, is enough to close up any warpage gaps after they have been cleaned up. Again, this is just what I have been able to read online. Curious to hear what others have seen in their experiences since my manifolds are already drilled and tapped for the EGT probes.

Those Ti fasteners look amazing! I'll probably end up going with those or something similar, I just wonder how well the Ti will work with the cast manifolds since the two different metals will expand at different rates...

 

I used the BD manifolds when i did the KDD heads, they are extremely stout

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1. Should I clean up and reuse my OEM manifolds instead of replacing with the BD Diesel manifolds? A lot of reading on the subject suggests the performance gains really aren't there for the $550-$600 investment.

I saw no measurable gains after putting the BD Manifolds in with my relatively stock set up that has theCAT and Muffler restricting the exhaust. When I first installed them, I thought I saw 100 degree EGT drops, but if I did, it was only slick driving on a highway. I’m still limited to 5o MPH towing up 6% grade while toowing 11k before my EGTs reach 1300 degrees and I’m forced to slow.

I have no idea how to where to or how much machining the OEM heads would be.

2. What manifold gaskets have people had success with in the past? I know there is an OEM part, but it seems like people have had good luck with the Vincos, CNS and other aftermarket gaskets. They are all very inexpensive, so I would prefer to use what people have actually used and liked.

I used COMTECH gaskets. It was a two plied ringed type gasket, I think $40 for the set.

3. Obviously I will be replacing the fasteners for the exhaust manifolds. Is there a preferred aftermarket alternative, or should I just use OEM fasteners again? They seem to rot out fairly quickly, so I would hesitate to put another set on.

Good of you to think of that. 1 of 3 of My rust free screws stripped while taking them off. I think OEM or the BPD ones mentioned would be good.

4. Any tips or tricks to make the project go smoothly? I plan on blasting them with penetrating lubricant for a few days prior to starting the project and removing the fender liners. Having a manual transmission means I don't have to worry about the trans dipstick, so that's one less bolt I have to undo. :grin:

I got the drivers side relatively easy. Moon type wrenches helped unbolt the manifold to Y-Pipe Screws. I gave up on the drivers side after my hands did not fit in with a wrench to get enough torque to take. the bolts off. Brought it to a shop to finish it up. For stuck bolts, I had some luck with the CRC freeze off. I have sinnce bought a small MAF torch and think that would have done even better.

 

The BD's are really nice looking but I can't see spending that kind of money unless it's a "budget be damned" kind of project. I'm betting it's like the Banks IC kit in that the gains vs. dollars spent are very small. If you're looking for performance gains there are better places to spend your money.

k

 

When I did my passenger side, I just used a Dorman manifold replacement kit. It came with the gasket included. I did take the liberty to purchase OEM Ford fasteners however. So far it has held up well - I know the driver's side has more milage on the same replacement setup. Again, has held up well. A cheaper option to consider...