I have to build headers for a couple small block cars in the next year or so and I'm trying to find a source for LA/Edelbrock style header flanges and UNWELDED stubs. Header flanges are easy to find, and I can buy the flanges with the stubs already welded in, but I would like to find either just the formed stubs, or unwelded stubs and flanges. I made a mandrel to swedge BB header tubes years ago, but you only need 1 for BB's - but I would pretty much need to build 4 different mandrels to do a decent job for LA ports. So, anybody know of a source for the unwelded stubs? And any other good sources for mild steel mandrel bends? I usually use Columbia or SPD Exhaust, but I'm always looking for other vendors for better pricing. Thanks

You might find something here.
https://board.moparts.org/ubbthreads/ubbthreads.php/topics/2184167/1.html

Speedway motors, a mile from me & my former employer has many varieties of mandrel bends (appear to be good quality) & flat SB flanges but they ain't accurate (catalogue is online). If you need something cutout I would suggest Jerry at SD concepts, a member here, he cut some intake spacers for me & they were dead on. If I was doing that I would get some flanges cut so that with the stubs installed they match the head ports as closely as possible. EDIT The speedway flat flange cutouts do not not match the head ports, not even close.

Thanks for the replies.

I had seen 408 S'D's flanges before and they are top notch, but I don't know if he does LA ones, and if not, it looks like he has a 10 set minimum to design them.

R/R - I saw Speedway's selection of bends and will consider them for the mandrel bends - probably just buy a header kit and improvise.

I'm just hoping to find some unwelded stubs to avoid having to make mandrels to swedge a set out. I've been considering buying a 3D printer, and designing a set of mandrels and flanges may be a neat first project for one. Print a set of proof templates in plastic and then use the file to CNC a set.

Hooker used to make a kit with flanges,gaskets,bolts and unwelded stubbs for 1 3/4" primarys but it seems to be discontinued. If someone has an older hooker catalog you may be able to find a partnumber in it and i bet they are still sitting on some shelves somewhere.

Dang. You are doing things the SMART way....

I made my headers for my Hemi I made 8 separate header stubs curving straight off the flange, all hand formed.

You want to find a way to make things difficult, drop me a line.....

Yeah, I had remembered seeing one of the companies selling un-welded stub kits a few years ago, but I couldn't find them now. I may have enough room to make a set of adapter flanges, and kill two birds with one stone. The adapter flange would bolt to the head with countersunk allens and gain bolt clearance on the head flange, and the header flanges could transition to a round tube.

I guess when I get the car into my shop in a few weeks I'll be able to better plan out what I need to do. And it looks like I will have access to a full machine shop for another year - I thought I was going to lose my access to one in a few months, and I wouldn't be able to machine stub mandrels if necesssary.

Check Headers by Ed's website catalog.
Thing is, if you prefer to work with thick flanges, he may not have.
His approach is flat flat flat, so thick isn't needed. I realise that doesn't work for everyone but he's not mr accomodating. LOL

Thanks, I hadn't seen his website before. He doesn't list the unwelded stub kits on his website. I'll probably contact him to see if he will sell just some formed stubs, or flanges and stubs.

The flanges aren't really an issue. I can buy off the shelf ones reasonably priced, or make them on a vertical mill fairly easily. It's making the 4 different forming mandrels for the LA heads that I'm trying to avoid.

Calvin Elston and a few others have posted on Speedtalk forum that they will blacksmith a starter tube to the ports.

"If you are going to stretch it, have the tube align with the roof of the port and tack weld it, then stretch the tube to the floor. The match at the roof is the most important as that's where velocity is highest."
Posted in 340 street header questionsthread by 900HP Throttle's Perfomance

Last year when we built a set of headers for my 340 we learned about the variation in bolt hole placement relative to the ports (cast iron 340/360 heads). We suspect this is why off the shelf flanges we looked at have so much slop in the bolt holes. If you're real picky about getting your ports to line up nice, you may end up welding over and redrilling holes. We ended up having custom flanges made. I didn't check into what Ed had this time because the specifics of the project and also my builder prefered to work with St St flanges.

ps. Be warned that Ed can talk your ear off if you get him going. He does have very strong opinions... OTH he has some good ideas and his workmanship was very good. In particular I really liked the way he merged the primaries into the collectors. Below is a photo of the inside of the collector back from when Ed was making headers.

Thanks, Mattax. If I can't find the stubs, I think I have enough room for a 3/8" thick adapter plate and a 3/8" thick header plate. We've done a couple sets like this in the past for RB engines that worked well. I'll make the adapter plates pretty much to port shape, and counter-sink the bolt holes to use flat head allen bolts to attach them to the heads. We shape the header plate ports to transition to a fairly round tube, and can position the retaining bolts in a convenient location. Looking at 1 3/4" at the head port and stepping to 1 7/8" about a foot out.

I probably have another couple weeks before I get the car to my shop to find stubs, and then I will be able to make the decision on what direction to take.