header install for dummies

[1990LTD]

I have a set of BBK shorty headers that I want to install...I had my exhaust done from the manifolds back and I'm unsure how exactly the shop joined the manifolds to the new pipe..if they welded the pipes right on or flanged it or what..


Can I still install these things myself or will I need to get a shop to do it, since there's some non-stock stuff going on there already? I don't have any welding experience or equipment whatsoever so I can't see myself being able to do much.


I know I will need to get someone to weld in holes for o2 sensors in the headers anyway - Is that a pretty standard job for an exhaust shop?

[mitymerc]

The only headers I have installed on boxes have used either a mustang H pipe or an aftermarket x pipe which had provision for the o2's. You can get aftermarket bungs to weld into the headers. The BBK's should have ball type flanges, the muff shop will have to cut the stock type flanges from the cat pipe & weld ball types on to it. I think they may have to shorten the cat pipe as well.

[packman]

IDK if you can weld the O2 sensor bungs into those headers. My BBKs had very little room at the flanges for sensors; which I guess is why they put them in the H or X-pipes. The exhaust on my mom's CV is clamped and flanged together. The only welding needed were the hangers near the trans crossmember.


Packman

[pantera77]

They won't fit. You'd have to have some O2 bungs thrown on your down pipes, and most likely the flange (well "socket") changed to fit a mustang style header.

[Lincolnmania]

i'm sure they didnt weld the pipes to the cast iron manifolds
you will have to install the headers, but beforehand pick up a pair of o2 sensors for a 90 mk7 the longest ones you can get. and you will need two o2 bungs.......take the car to the exhaust shop and have them mate your pipe to the headers and install the o2 bungs and sensors.

[zoomie]

ok seeing as i have BBK 1-5/8 shorties on my linc i can answer that question right nice and quick. the headers fit, but wont fit the stock down pipes, i pulled my down pipes off a stang that already had the 02 bungs welded in,in addition the downpipes bolt on, you may have to fiddle with it a bit to make sure they seal correctly though. the first time i did it i had the passenger one hanging down too low.I also had to lenghthen the wires, but what the hey it works,and rather well. my machine isnt fast but its sounds nice heheh. now i dont have full exhuast but it weill have on the future at some point.

[1990LTD]

probably more stupid questions, but....

I'm going to slap the headers on the first chance I get, but, I'm going to get the exhaust shop to do the welding of flanges and o2 sensor bungs and such since I don't weld (yet).

I know an EFI car needs o2 sensors to run properly, but would it be at all possible for me to pull the manifolds off, bolt the headers to the cylinder heads, and drive it 10-15km or so (with no o2 sensors) to the shop for welding and final install? I know I'd be venting exhaust into the engine bay but I could baby the car there easily enough so as to (hopefully) not melt anything.


Would I be wise to get them to install the o2 bungs on the headers before I bolt them up?


I basically want to remove the manifolds and bolt up the headers myself at home, but get the shop to do anything that involves welding, I'm just trying to figure out the logistics

[Pirate]

I know an EFI car needs o2 sensors to run properly, but would it be at all possible for me to pull the manifolds off, bolt the headers to the cylinder heads, and drive it 10-15km or so (with no o2 sensors) to the shop for welding and final install?

No. Someone could die.

[1990LTD]

No. Someone could die.

They had it coming.



Any dangers besides that?

[Pirate]

They had it coming.



Any dangers besides that?

You could die.

[87gtVIC]

I believe it would be difficult for them to weld in bungs while the headers are installed, so it would be better before hand. Just one thing....I spoke with Thain about this before and he mentioned that in the collector you would only be getting readings from one port. That is why oxygen sensors are normally mounted down stream just after all ports mate up.

You can drive the car just fine. It would just be loud as fuck.

[1990LTD]

Ah, so should I have the sensors put in the headers as far down as possible? Or do you mean putting them in the downpipes?

[87gtVIC]

From what I have learned it seems that the down pipes would be the ideal location simply because that is where all of the gases are mixed.

[sly]

+1 downpipes

[1990LTD]

Cool, thanks guys. I will likely then bolt them on myself and bring the car to the shop to have them mated to the downpipes, then have bungs welded into the downpipes.


What gaskets shall I need, just the manifold gaskets? Are there gaskets at the flanges?