I have a 1977 f-250 camper special, supercab with 8 ft. bed, 2 gas tanks, 2 wheel drive, with a 351m. The aux. gas tank runs between the drivers side frame rail and the drive shaft. I've been wanting to put a set of headers on it and run duel exhaust. I would like to run the exhaust all of the out to come out the back but would put it out behind the back tires if I had to. Summit Racing has an exhaust kit for everything like my truck but will only fit 4wd. Any ideas without buying a custom exhaust? Thanks for any info, Kirk.

 

Let's start with the headers..........
Unless you go with shorty’s or actual custom built headers, 99% of all headers will require "massaging" to install (whether it's denting a tube, moving a bracket, etc.). Unless it is for racing purposes, in all reality, there are little differences in overall performance between shorties (Tri-Y), mid-length & long tube headers.....shorties actually perform excellent up to about 5500 rpm and then will have a slight drop until 6k rpm when it begins to really decline.....more than enough for street use and much better than oem manifolds.

Hedmann in the 60's/70's an excellent product and considered one of the top mfg's with Hooker....they were built in Culver City, Ca until about 10 years ago. Beginning in the late 80's Hedmann quality began declining & today, they are considered an "inexpensive Header", meaning, you get what you pay for- but it appears they have brought back their "higher quality" line. IMHO I would place Patriot & Blackjack in the same category. In general, the head plate should be at least 3/8" (1/2" is best), tubing should be at least 16 gauge (14 is best).....otherwise leaks and burn-though are going to be a problem as well as the longetivity of the headers.

"Custom exhaust kits"

Waste -o-money......plus the quality...well..likely Chinese knowing Summit

For reference, WyoTech, Hot Rod Magazine has numerous published articles on this. On the net, please read:

broaderperformance.com/muffler_flow_tests.htm (Independently tested cfm flows of the more popular mufflers, glasspacks and resonators @ 15” wc:
2 ½” diameter straight pipe 521
2 ¼” diameter straight pipe 365
2” diameter straight pipe 283
2 ¼” diameter tailpipe 268
2 ¼” round glasspack- no louvers 274
2 ¼” round glasspack- with inward punched louvers 133
2 ¼” round glasspack- inward punched louvers/installed backwards 141
2 ½” inlet/outlet Dynomax SuperTurbo 268
2 1/4” inlet/outlet Thrush CVX 260
2 ½” inlet/outlet Flowmaster 2-chamber 249
2 ¼” inlet/2 ½”outlet Cherry Bomb turbo 249
2 ¼” inlet/outlet Flowmaster 3-chamber 229
2 ¼” inlet/2 ½”outlet Maremount Super C (OEM Replacement) 149
2 ¼” inlet/2” dual outlet Maremount 183
2 ¼” inlet/outlet California Turbo 229
2 ½” inlet/outlet Hooker Aerochamber 324
2 ½” inlet/outlet Hooker MaxFlow 521
2 ¼” inlet/outlet Maremount Cherrybomb Vortex 298
2 ½” inlet center/outlet offset Borla Turbo 373


http://www.popularhotrodding.com/eng...../index1.html (this is an in-depth article that tests not only the mis-conception of flow demand but also how placement of a muffler (a glass pack in this dyno test) can actually "fool " the system into thinking that it is essentially a straight pipe.

Check out a local shop, they will bend up exactly what you want and you get to pick the tone of the muffler that you want..........and can adjust it if you don't like what you hear.........
While there are mufflers that will out flow a glass pack design, it also depends on the design. Allied resonators (that sell for $20-$40) each and available at any muffler shop) flowed 90%+ of a "race spec muffler". Others using other brands consistently showed similar results.

 

The headers will exit on either side of the transmisson so you will need to cross the drivers side over to the passenger side. I did mine by the tail shaft. From there you can go where ever you wish. I bought mandrel bent pieces and fabed up a system myself. On another truck I took the mandrel bent pieces to a shop and had them use those for the 90 degree bends and they used the ram to bend the rest to fit. Not a fan of ram bent exhaust because they can crush the tubing really small on big bends. Unfortunantly there are no kits for our trucks.

 

Not sure if there is much difference but read my posts here.

https://www.ford-trucks.com/forums/1...al-shocks.html

 

Thanks for the quick reply everyone. Beechkid, great information. I'll definitely be looking for a good quality header. I'm looking to improve gas mileage. Hoping to change cam, ignition, carb, that kind of thing. Thanks again, Kirk.

 

If it helps, I installed Hedman headers on my 75 f250 460 supercab, dual tanks with dual exhaust.

I ended up having the pipes ran under the frame and between the body and frame rails. No cross pipe, exhaust exits in front of both rear wheels.

 

retrof250, thanks for the reply. This looks pretty interesting also. Did you have a shop bend the pipes? These threads are awesome in the way I can get information for my truck. Thanks again, Kirk.

 

Yes. I actually had an exhaust specialty shop do all the exhaust from the collector pipes to the exhaust tips. Bend, fit and weld. I did have to move my electric fuel pump from the outside of the frame to the inside before I had the exhaust installed.

 

Pics of mine. You get the idea.

 

Retro - All the Hedman headers I see for my 78 4X4 F250 SC are fenderwell exit. Do you have more specific info on yours?

 

Here is another option for what it is worth

 

if youre gonna run em outside the framewell (by far the easiest choice) your best bet is to start with fenderwell exit headers. More room for the headers, more room for the pipes.

 

Hey, this is actually retrof250 - I had some issues logging into my old account. Got it all fixed -

As for which headers I used, they were the Hedman 89140. Not sure if they work the same on the 78 and/or 4x4.

http://www.summitracing.com/parts/he...rd/model/f-250

 

Those are 4x2 headers. Same ones I have.

 

Does anyone see/know an issue if you ran both headers into one 3" pipe, run that all the way back to axle with a glasspack/muffler in between, then split back off to 2 2.5" pipes straight out the back? That's where I've been leaning on mine. I just think it will be cleaner with a single pipe as far as I can go.