HO headers on!!!!

[Grand Marquis GT]

Weld a bung into a side of the downpipes, and extend teh wire..

[Blaze86Vic]

Here is a pic of what was done to my stock exhaust to acomidate the headers that were on my engine.

An aditional flange was added, and a nut was used to hold the O2 sensors (I told you guys it was done low budget)

[gadget73]

I didn't even add more flange to mine, just cut the ends out of the bit that holds it onto the header outlet. Mine also have nuts welded onto the stock H for O2 sensors, but I screwed up the location of one of them and now it sits on the frame.

[Blaze86Vic]

If you didn't need to add a flange then it stands a good chance that the headers are not 2-1/2".

[gadget73]

Headers are stock 1988 Mark 7. I think they're 2.25", but can't be sure.

[DuceAnAHalf]

Has anyone done a back to back test comparing these headers to the stock manifolds or even aftermarket headers? I ask because i have always thought that the HO headers looked kinda restrictive because of the indents and kinks in the tubes. I know they will obviously flow more than the manifold but any idea how much more?

[gadget73]

Agreed, stock headers can't flow all that well compared to a good aftermarket one, but they're better than the iron, weigh less, and can be had dirt cheap most of the time. I would be interested in seeing either dyno runs comparing them or a flow test or something that would show exactly what gains can be had from a set.

[Blaze86Vic]

Actually all those dings and dents are there to create a better flow rate. Some after market ones might have a better flow rate, and if they do it's because they used larger primary tubes.

[85crownHPP]

theres a 5.0 stang that comes to the shop now and then... we put some flowmasters on it a while back, and Im wishing he would get some headers so i can recycle his stock ones

[NATEHAWK]

i gotta get mine on

[grandpaslincoln]

GL has some more low end grunt now. I noticed when I floor it, the front end lifts up more than it used to. The exhaust is definately louder now when I am driving around. Oh well. If anyone don't like it, they can just get earplugs, cuz I don't give a fuck lol.

[Mr. Land Yacht]

sweet headers!
I got them, too!
i got mine for 70 bucks froma friend and put them on with my uncle's help...
after the headers i have duals with no cats, no mufflers...just 2 glasspacks..sure is loud.
next is bigger cam, fuel injectors, and bigger throttle body...nice huh?

[grandpaslincoln]

nice! Continentals are cool. I got the HO headers, with no cats and summit performance mufflers, it's pretty damn loud when you romp on the gas! The only problem I had really, was getting the downpipes off of the old manifolds. On the left right one, I had to cut one of the studs to get the downpipe off. Oh well, they are junk anyway.

[phayzer5]

For those not in the know, this is why they dont just bolt on and go with stock exhaust:

[88grandmarq]

Actually all those dings and dents are there to create a better flow rate.

Are you serious !! ???

the stock header tubes are crimped for 2 reasons, none of them are to "create" flow.

Reason #1) Ford used the same mounting hardware to mount the headers as they have been using on the manifolds since 1968, which have a large locking washer incorporated on the bolt/stud. they call it Ramp Lock.

Reson #2) they used, large, automatic torquing machines to tighten the bolts when on the assembely line.

also the drivers side header is flattened on the second or third tube to clear the steering shaft when the engine was put in the car from the bottom.

stock headers flow better because the collector flange opening is bigger then the stock manifolds. Most of the stock manifold openings are around 2" inches are smaller.