Today I spent the entire day in the garage. Yesterday I met w/ the turbo supplier. He said the my turbo should've been in, but naturally, it wasn't. So instead he mocked up a turbine, and compressor housing so I could build the header. My T-4 flange did come in, so all I needed was the mock up housing to get started.
( Actually, I started building it Wednesday, but now that stuff was getting critical fitment -wise,...I thought better of plowing forward until I had the actual turbo)
I don't know,....maybe I'm getting old(er), but it seems that despite the fact that I spend all day doing something,....there is still an unfinished project left with stuff to do. That is the case again today.
But,..(I digress). When I went down stairs, this is what I had staring at me:
For those of you that have never built a header from scratch this is the process:
1. Take an elbow, hold it up against the header flange ( the one you built from scratch last week).
2. Close one eye, pull the welding hood down, and buzz a small tack weld to hold it in place,...based on your eyeballed judgement.
3. Cut a segment of straight tubing,.....hold it up against your newly placed elbow. If it looks good, get your grinder and **bevel the mating surfaces to insure good weld penetration. If not, take the same grinder, and "modify" the mating surface angle until it fits the way you want it. When it does,....bevel the weld surfaces. While holding the piece w/ one gloved hand, use your other hand to "feel" the fitment, to be sure that you are not welding the thing at some goofy-assed angle. When you are happy w/ it,.....buzz a couple of small tack welds.
** The only reason I have to bevel these tubes in preparation for welding is because I'm using mild steel, 1.5" i.d. .145" wall steam pipe, since this is going to be a turbo header. Standard wall tubing ( 16/18 ga.) requires no prep, other than making sure the tubing and angles line up properly.
4. The process marches along like described above until you have an entire tube completed. Once that is accomplished, break the tack weld from the header flange,..and weld all of the joints for the entire tube. I chose to grind the welds smooth after that, purely for aesthetics. You could leave the snag-u-lated welds standing proud for all of your homies to see online if you choose,..and if you do,...expect a smart assed comment from me dogging you for displaying those same "less than T.I.G. quality welds". Besides,..w/ tubing that is over an 1/8" thick,..there is plenty of weld holding the tubes together even after grinding the joints smooth,..so I had nothing to lose.
** As a foot note to the above,..it's important to realize that despite the fact that you are grinding steel outside,....in the open air,.....you are still creating a fairly significant amount of dust. While you may disregard the notion that there is no way you're actually breathing any of that junk in (considering the open air and all), you may wanna think twice. After a day spent grinding all of that steel...you are in fact breathing an entire erector set into your head. You may elect to use a respirator.
Now I on the other hand, choose to ignore my own advice. I think it shows progress when after the work is done, you taste iron in the back of your throat, spit and blow black snot out of your head for about an hour afterwards.
* note to self:.......use a respirator next time.
5. After the tube is complete, and ground smooth,.I reattach the thing to the flange w/ a much more serious tack this time. and move on to one of the adjacent tubes.
** This header is for a twin scroll turbo. Kinda like a twin-turbo system w/0 the twin turbos. The T-4 flange is divided, wherein one half of the engine feeds one side of the flange,..and the other half feeds the other. The design objective then was to build (two) three equal length tube headers to accommodate the twin scroll flange. The benefit to a twin scroll turbo is that it takes advantage of the engine's exhaust pulses more efficiently, and in theory spools the turbo more quickly. If there is a down side to the system,..is that it requires a more intricate header design,....and two wastegates.
Now as a dislaimer in advance,....my header submitted here is certainly no example of some intricate design.....it is actually pretty crude by most twin scroll headers out there. But it is functional,...achieves the design criteria to make the twin scroll turbo work properly, and because it's built out of steam pipe,...should last forever.
The end of the day had me at this point:
I made the two center tubes drop lower than the outside 4 tubes in an attempt to even them up length-wise. What I ended up with was in fact two center tubes that are 1" longer than the #1, and #6 tubes instead. I could leave it and say WTF,..but again that's not me. I'll probably end up cutting the damn tubes and shortening them comensurately. I hope I can get the welder all the way around the tubes after I do that. ( I think I can).
The turbo will sit about even, or slightly above the valve cover when you draw a line across engine compartment.
The oil drain will angle back between the opening between tubes 3 &4,.( I'll use a threaded pipe nipple to avoid the hot-assed header,...once I get it south of that,..I'll change it over to -10 from there)
I'll make a simple colloctor so that each one of those three tube clusters will neck down small enough to feed one of those tiny little holes on the T-4 flange
It looks like a mile above the tubes,...but it's actually about 5".
An additional note worth mentioning is that while working with gloves is cumbersome , and you have no sense of feel w/ them on,....just as soon as you tell yourself that all you're gonna do is just tack this piece in place,...a little molten ball of weld spatter will almost assuredly land right in the palm of your hand.....( as evidenced above, by the little brown dot)
That brings you up to date again.....I should be able to finish them the next time I go at it,..and I'll post the "done" pics when that time comes.
Cya.