Would headers help me with HP or MPG?

I have a stock engine except for an MSD 6a box and a K&N drop-in filter.

I have a speed density, 302, 1989, 3.55 rear end, AOD F150 XLT Lariat.

I noticed the right side exhaust manifold is cracked all the way thru between the 2 & 3 cylinders, while doing a tune-up. The last tune-up was in 1995! It may have been cracked a while.

Do I need to change it? Should I put in an OEM replacement? Should I replace both sides with headers? If so which one?

Thank you,
Lance

p.s. I have a bad back with only 20 - 120 minutes of physical activity a day. A tune-up is a three day adventure for me. What ever I do, It will be a major undertaking. I don't want to do more than I need to and I don't want to pay a mechanic if I don't need to.

p.p.s. Before my back problems, I had rebuilt cars from the frame up, engines, trannies, transfer cases, entire wire harnesses, and body work.

 

Headers do sound nice on the 302, and they will flow better, if the rest of the exhaust flows well. As a stand alone mod, set your expectations low for performance/mpg gains. However, if you compare the price of a new set of headers to the price of a new manifold (dealer only?), I would bet that the headers come out cheaper, depending on the set you choose. Of course nothing's cheaper than a junkyard manifold. If you do choose headers, make sure you get a high quality set of gaskets. Some headers come with cheap gaskets that might have you doing the job twice .

As you prolly already know, this job is hard on the back, as well as some other joints. You will be reaching all the way into that engine compartment for quite some time.


Good luck!

 

I see a set of MAC shorties in your future........Or a junkyard manifold for which ever side is broke. This would be the easiest/cheapest way out, only doing the side that's broke.

 

With an intake to get more air in, it'll help.

Definatly a PITA job, start soakin the bolts like yesterday.

Adrianspeeder

 

in your situation I would just get a junk yard manifold and put it on. it is the easiest and cheapest way to go.


Bruce

 

agreed, my headers were a total pain to install i bolted them to the motor and tried doping it all in at once.nope. tried with the motor in the mounts.nope ended up having the motor hanging a little from the hoist and i still had to beat the pass side so it would clear the frame long story short if you dont want the sound or powerr you just want it fixed i would go with a used manifold.

 

Thank you!

I can get a new OEM manifold for ~$79. I'll get my Volvo mechanic to replace it or a muffler shop a couple of miles from here (recommended by the local speed shop).

I won't pull one out of a hulk in a bone yard, even if it was only $1.00. I know the cars/trucks on the 4 x 12" diameter cylinder junk yard stands are supposed to be stable, but... I will not get under a car or in the engine compartment. It is too scary.

I) In '62 or '63 my neighbor's 16 y.o. son had his yellow '57 Chevy on jack stands. When his parents came back from a long weekend outing, they found him crushed under the car. A senseless and frightening loss.

II) In 1985 my Dad was crushed and partially crippled when a tow truck cable snapped and his '75 Ford LTD country squire fell on him. To this day I don't know exactly what happened, he has not spoken of it at all. I don't think he remembers it.

I don't get under a car, or reach into the engine compartment, unless the car has 4 tires on the ground, with the parking brake set, the tranny in "P" ("1" or "R" if manual), and the wheels blocked!

I keep my boneyard acquisitions to items that I can't hurt myself obtaining, such as dashboard *****, light fixtures, and air-cleaners.

Thank you,
Lance

 

Will it hurt to leave the broken manifold on?

It should only be positive pressure of hot air in there. No cold air can enter thru any exhaust valve or thru the manifold crack.

Thank you,
Lance

 

I can get a mechanic to replace the manifold, parts and labor for $200-$225. Is that a good deal?

Thank you,
Lance

 

Not too bad..........

 

All done!

A local shop did it for $206 parts and labor.

It was very easy on my back. I did not have to bend to work in the engine and my wallet is lighter!

I did not realize how much noise came from the broken ex manifold. It is much quieter now.

-Lance