Ranger50 HalfDork
1/3/11 10:05 a.m.

First off, I don't have anything or really anywhere to make what I want, a header adapter plate. I would love to have a drill press, but no where to put it. Hand drill won't work either, need to be a bit more precise. Also, no real machine shops here in Eastern BFE KY, plus they would be super expensive vs making them myself and hurting the budget.

So, any suggestions for/on the cheap?

Giant Purple Snorklewacker
Giant Purple Snorklewacker SuperDork
1/3/11 10:07 a.m.

Fire wrench (oxy torch) and an angle grinder.

nocones Reader
1/3/11 10:08 a.m.

buy rusty old headers and cut off the flange?

I've made header flanges out of 1/4" - 5/16" before with good success. Alot of places have blanks available (unless you are making it for something real strange). You need to borrow a plasma cutter or torch rough cut it and spend some quality time with a die grinder and your exhaust manifold gasket.

Ranger50 HalfDork
1/3/11 10:52 a.m.

The header bolt pattern is staggered and I need it turned/flipped to use the original bolt pattern, reason for the adapter plate. Available flanges are not available in over a 3/8". The bolt is 25mm long, stock.

Original manifolds are cast iron, so no go on an existing equipment.

Streetwiseguy HalfDork
1/3/11 12:45 p.m.

Unless you want to torch it and spend the rest of your life grinding, find a waterjet or lazer place and take them a template. If you talk to the right guys, and can wait until they are cutting something from the material you want to use, it won't be a ton of dough. Trick is to find a shop that specializes in small batches and custom work.

Dr. Hess
Dr. Hess SuperDork
1/3/11 1:18 p.m.

Yeah, knock out the CAD work, bring it to a waterjet place and let them do it. That's what I do.

tr8todd Reader
1/3/11 4:34 p.m.

If your engine is fairly common, try calling a company that makes headers for that engine and see if you can buy just the flange. Try Kirk Racing Products. I used some old rusty headers and cut away the tubes last time I needed a flange set.

kb58 Reader
1/3/11 4:56 p.m.

I'm assuming you don't have any appropriate tools, so it's going to involve money. Take it to somone with a mill and they can make you a one-off set without going to the bother of CAD.

Ignorant SuperDork
1/3/11 6:03 p.m.


Giant Purple Snorklewacker
Giant Purple Snorklewacker SuperDork
1/3/11 6:26 p.m.

You could use a shotgun to clean a spot on a 1/2" or 3/4" thick plate but you ain't gonna make any holes even if you use Sabot slugs.

Ignorant SuperDork
1/3/11 6:38 p.m.

shotgun is the answer on here for when someone asks "how do I" or "what tool do I use"

See old post about guy using shotgun to remove bees from truck.

Edit... It was a guy who tried to remove a lugnut with a shotgun.. http://archive.grassrootsmotorsports.com/board/viewtopic.php?id=30959

Streetwiseguy HalfDork
1/3/11 7:19 p.m.
kb58 wrote: I'm assuming you don't have any appropriate tools, so it's going to involve money. Take it to somone with a mill and they can make you a one-off set without going to the bother of CAD.

CArDboard will work nicely.

Jensenman SuperDork
1/3/11 8:28 p.m.

So you need to make an adapter plate with two different bolt patterns, right? I'm going to say one pattern will probably use countersunk head screws to attach the plate to the head and then the other pattern will be threaded to accept bolts/studs, right?

If so, you are going to at least need a drill press to do this on your own. Can you use a benchtop version?

porksboy SuperDork
1/3/11 8:43 p.m.

I have used old header flanges and much quality time with a hack saw, file and drill press and torch to make my own. Hack saw and file to get the shape, Drill for the bolt holes, Torch to fill in un wanted holes and start the port holes.

Lots of time wasted and little gain. Should have sprung for tha propper hearder.

Ranger50 HalfDork
1/3/11 10:58 p.m.

In reply to Jensenman:

Hit the nail on the head. I need a 5.7 Hemi exhaust bolt pattern reversed. The factory igits staggered the pattern the same way on both heads, so you can't flip or turn the factory stuff side to side. Plus the EGR port on the passenger side head.

I have already priced out the cheapest flange I can get at $39 EACH and then it's only 3/8" thick. Wrote an email to one of the companies that offer Hemi headers, but no response yet.

Nashco SuperDork
1/4/11 3:07 p.m.

Why isn't 3/8" thick enough? Can't you remove the old flanges and install new flanges instead of doing an adapter? Heck, if this is for the $201X challenge, is 3/8" even necessary? I've home brewed manifold flanges with thinner flanges...not great, but when making due with scrap material on a for-fun project, it worked.


Ranger50 HalfDork
1/4/11 4:11 p.m.

In reply to Nashco:

OE manifold is cast iron and HEAVY. Stock engagement is 20mm or so for a M8 thread.

It may be a fun project, but I believe in only doing something once, if possible. Especially when it will be a only vehicle for me DD.

tuna55 Dork
1/4/11 7:19 p.m.
Ranger50 wrote: Stock engagement is 20mm or so for a M8 thread.

No? Usually three threads are the min, maybe four if you're getting anal. Four threads on a M8-1.25 is 5mm. I am not saying you should make it thinner, but 20mm is crazy overkill if thread engagement is your only criteria.

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