so im apparently stuck with the non-fitting cheap ebay header for the mazda. I can work around the EGR mount being in the wrong place. but the collector hits the oil pan, making the head flange holes not line up, or the head flange seat. it seems that the tube is bent a few degrees to far. like 1/2 inch down at the collector would solve all the fit issues besides egr. its a header for a 03 protege5. 4-1 design, with the collector being a pipe with a roughly 90 degree bend.
essentially id like to open the 90 degree bend to something less than 90, like 80 or so.
how is the easiest way to do this? I was thinking of bolting it loosely into place, jamming a pipe into the outlet, and hanging off the pipe on the lift. but this would probably damage the threads in the aluminum head.
I also have a 16 ton harbor freight shop press, but cant think through how that could be used to open the bend.
I'm out of oxy-acetaline. so heating (unless I can do it with mapp gas) is out.
I would not hang off of it bolted loosely like you're describing. Can you get one end in a vice and work that way? Heating it wouldn't hurt. You could also cut a wedge shape out of it and weld it back together.
with it being stainless, I don't think I can weld on it. granted, I may be wrong, or it may be a type that I can weld. it is, after all, a cheap ebay header.
will mapp gas get hot enough to help?
Anything will help at least a little- I'm thinking you try clamping the "block" end of the thing in the vice, get it as hot as you can in the area you want to bend, and try your pipe/lever idea.
worth a shot!!
also had the idea of taking it to an exhaust shop, but they may charge more than its worth, causing me to piss good money after bad.
and hopefully it doesn't take too much force. the workbench the vice is mounted to isn't bolted down....
When my downpipe for my old mercury needed some bend taken out because the exhaust shop bent it wrong i used a little propan torch and 6 foot of fence post. It was annoying but we eventually got it too fit and seal on my header.
Put a couple scrap 2x4 on the floor, and bolt through two of the flange holes into the wood. Then you can stand on the 2x4, put a piece of iron pipe in the collector and lift up. Heat the area that you want to move before lifting. You have a lot more strength/control doing a lifting motion than you would in a pushing down or lateral motion.
I recall seeing an old timer who bent all his headers by hand filling the pipes with sand before heating and bending. Helps to preserve the tube shape, distributes and retains the heat better.
