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Topic: I need to get a better understanding... (Read 1973 times) previous topic - next topic

I need to get a better understanding...

I have no problem running a clean car (emissions), especially if removing the smog pump only gets me 2-3 hp. I just had a new duel exhaust system and I put new cats on mainly because they keep our air cleaner and they are free flowing. My question is this.... I bought some Ford stock headers. I realize they don't give much if any in hp., but they do give the car a deeper throaty sound (which I like and I will put them on when I put on new aluminum heads). The problem is every header I see does not have provisions for the O2 sensors. If I leave them off won't that eliminate my EEC from letting me know if there is a problem with my cats.? Will this cause my EEC to try and compensate causing my car to run badly or will it just throw codes? I realize that there is more to my smog pump such as the air tube that runs to the back of my heads. I will loose a little weight, but will my car run as clean with only the cats and is it really worth it in weight and hp? Thanks!

I need to get a better understanding...

Reply #1 –
When installing headers, shorty headers, the O2 sensors are moved to the H-Pipe. Stock, and even aftermarket H or X pipes have the provision for the sensors. Although it's often necessary to lengthen the harness a bit for them. You need the sensors. The headers will not bolt up to the stock exhaust, so, start looking for a new H-pipe. The H and X pipes for the Fox Stang will bolt right up to the headers as it should. Install the sensors into the new pipe, and then have the ler shop adapt the rest of the dual exhaust to fit the H-pipe with ball and socket connectors as Ford had it.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

I need to get a better understanding...

Reply #2 –
You need the sensors. They aren't there to let you know if there's a problem with your cats, they're there to let your EEC know whether the engine is running lean or rich so it can adjust fuel accordingly. If you go without them the EEC will default to pig rich, your fuel economy will drop by a large amount, and the car won't run as well (you will lose HP because the EEC dumps in too much fuel). Only '96 and later cars have a second set of O2's downstream of the cats to monitor their condition.
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

I need to get a better understanding...

Reply #3 –
Vinnietbird and T/C,
                          Thanks, for the great information! Right now I have the stock Mustang exhaust manifolds. From what I have read here, they are not restrictive at all. They also have the new O2 sensors installed. So, if the "shorty headers" don't add much HP then maybe I should put them on my "71" Ford LTD convertible. It already has an "H" pipe and I have the heads off it as we speak. As you already know it has no "EEC" so no O2 sensors to worry about and with a 351W the shorty's will bolt right on. I think my Cougar would benefit more if I put that money towards the aluminum heads, rockers, lifters and push rods.

I need to get a better understanding...

Reply #4 –
The stock Mustang had headers, not cast iron manifolds. The Bird had cast iron. The factory Mustangs had tubular headers, and from what I have heard, they are a bit more restrictive than aftermarket, but for a mild build, they will work just fine.....and they can be found for a pretty fair price.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

I need to get a better understanding...

Reply #6 –
My Mustang HO engine came with iron manifolds and I bought a set of Ford headers from a salvage yard. Yes, they are smaller than aftermarket headers, but being they are from Ford they have all the hammerings needed to fit right on. I bought mine with the rear axle together.

I need to get a better understanding...

Reply #7 –
Quote from: TheFoeYouKnow;414029
I run Mark VII o2's, they're 3 inches longer and they fit perfect.

Is there anyway you can shoot us a picture?

I need to get a better understanding...

Reply #8 –
I don't have any handy, but there isn't really anything to see except that the wiring is longer so they can reach the connectors once moved down to the h-pipe.
 

I need to get a better understanding...

Reply #9 –
Quote from: TheFoeYouKnow;414057
I don't have any handy, but there isn't really anything to see except that the wiring is longer so they can reach the connectors once moved down to the h-pipe.

I got you. Really, the set up I have now is quite nice.  I don't think I will benefit much messing with it, now that I have a better understanding on how all those parts interact. Thanks!