Hey guys!
I have a 1995 f150 with a 5.8 on a MAF system. I have been looking into the posts regarding upgrading the performance of my engine, and everybody aways suggests long tube headers as one of the first things to get.

I spoke with an exhaust system tech recently, and he told me headers are a waste of money for anything other than a race car. After doing some research on long tube headers, I have to say I'm inclined to agree with him, as I found those long tube headers mainly help with exhaust scavenging, and exhaust scavenging mainly occurs at higher rpms. As we all know, our stock 5.8s are not really high revving engines by any means.

Now I do understand the whole thing about restrictive manifolds, but are those manifolds really that terrible to make any sort of noticeable difference if changed? The tech I spoke with said that the biggest difference that could be made to the stock exhaust system was to first free up the cat-back portion by increasing the diameter from 2.5 to 3". Other wise without that change, any advantages that might be gained by new headers would be stifled by the rest of the system, if any gains are to be had in the first place.

So what do you guys think? If somebody is just looking for a little extra power and not a flown blown racer, are those long tube headers really worth the price?

 

Parts don't make power, systems make power. You are doing the right thing to ask before you start spending money. Headers will help in almost any situation but how much? You have to make more RPMs or more cylinder pressure to make more power. The headers have to be part of a system to make more pressure or more RPMs.

The exhaust port is really restrictive and the intake is also. The shape of the combustion chamber is not great either.

There are guys here who can tell how to make more power without wasting money. I'll let them do it.

 

Generalizations about exhaust systems is not what you will find here you will find Ford truck specific information based on first hand experience. The first thing I have to correct is your theory of exhaust scavenging, that occurs at all rpms but where an engine needs the most help is at low rpms where exhaust gas velocity is at it's lowest. Here long small diameter head tubes generate more vacuum than a larger diameter exhaust pipe which helps pull the next exhaust pulse out of the cylinder, and that in turn generates more torque. So yes longtubes are beneficial on these trucks.

Stock manifolds are restrictive but so are the stock cats and Y pipe. If you want to test your exhaust techs theory on cat back systems just go get a chop saw and completely remove your cat back. Many here have done just that and guess what they found, the exhaust doesn't get much louder and the engine doesn't make any more power.. because the stock cats are one of the big bottlenecks on these trucks.

You are right in one thing, these engines don't rev very high or make a lot of hp, so big exhaust systems aren't necessary. The very best combination for a bone stock motor is longtubes into a custom 2.5" single exhaust, custom because there are no over-the-counter intermediate pipes available for longtubes on these trucks so your local exhaust shop will have to fab it if you can't do it yourself. 2.5" pipe will produce the best low rpm scavenging and still flow enough with an aftermarket cat or no cat to allow the motor to make as much HP as it is capable of.
The second best system you could put together would be with short tube headers, there are Y pipes available for these as they are designed to directly replace manifolds, and any aftermarket cat will out flow the stock units. All of this is a direct bolt on and therefore a potential DIY project if you have basic tools, this combo won't make quite as much low rpm torque as the longtube setup above but it will still be an upgrade over stock.

 

Aha! I was hoping to get the attention of the great Conanski! I feel you have some of the best knowledge about this when it comes to these engines. Thanks for the insight! I plan on getting myself some new heads, a much better flowing intake, new cam, and now possibly some headers. My cat on my current exhaust system has been... Emptied..... Having no need for emissions testing, there's no need for that or any of the EGR stuff.

I wasn't completely sure about what that tech had said, so I wanted to post a question to see what others thought. So thanks again for the clarification!

 

I put long-tube Hooker headers on my '90 F150 302 back in the day. They did something all right - they totally trashed my bottom end power. That thing couldn't pull your hat off from idle, but it was screamer above 3000 RPM. I took them off after about a year and went back to the stock manifolds.

 

Jas.. what was behind those headers? Anything bigger than a 2.5" single and that was your problem.. too much exhaust for a 180hp motor. I put a full MAC system on my '89 5.0 and got the exact opposite results as you.. hugh off idle torque gains. I put a bigger system on my '90 and got the same results as you.. lost off idle torque vs stock but gained everywhere else.

 

Primary tube size plays a role as well. I ran manifolds on my mild 5.8l build for a couple weeks, no front cat, healthy rear cat, into a 3" muffler after that, then I put long tubes on. The primaries are 1.625" ID into 3" collectors that neck down to 2.5", and then Y into a single 3" system. Nothing but improvement there, though most beneficial at 2k rpm and above.

 

Greetings guys. I'll share what I've done on my 95 F-150 Eddie Bauer W/the 5.0 L and on my 95 F-150 SVT Lighting W/the 5.8 L. On the 95 Eddie Bauer I installed 50 State legal headers (I live in California) and Cat back 2 1/2" dual exhaust for the purpose of wanting to improve MPG. I only drive the Eddie Bauer ~ three times a year at ~ 750 predominantly high way miles round trip, going fishing. I improved the mileage from 18.7 to 21.7 MPG and that is using the A/C with about 700 pounds of cargo at 65 MPH. On the Lighting I changed from OEM 4:10 gearing to 3:73 to reduced highway speed RPMs and installed 50 state legal Ford Motorsport headers. My last rip I took the lighting fishing, I recorded 21.4 MPG using cruise control at 65 MPH and A/C. On both trucks I did the air induction cheap upgrade that I read about a while back on the forum. Unfortunately I don't have the part number, but I'll explain and I'd imagine someone on the forum with chime in. I went to my local JY and removed from two 460 cuin engine the air induction intake plastic tube that is a direct mount in the 1992-96 F-series trucks. The OEM intake mounts on top of the radiator more towards the driver's side and the 460 cuin air intake tube mounts on the driver's side of the radiator. The 460 cuin intake tube has a larger opening allowing more air into the induction system and as explained earlier in the forum was cooler air because of it's physical mounting location. Supposedly with the air induction upgrade, there's ~ 7 plus HP increase. My thoughts, the cheap upgrade works perfectly, I'm able to maintain Ford OEM parts and the plastic intake just snap into the air filter box. If you pursue the air induction upgrade, ensure you clean the inside of the plastic tube while you have it out. Sorry I don't have pictures showing this.
I normally hang out on the 73-79 dent side forum, but do occasionally visit this one especially for any maintenance tips. And I'm about to pull the 95 Eddie Bauer out of storage for the first fishing trip, (July) this year, so I just learned about checking the inside of the distributor's shutter wheel and PIP for corrosion. Both good preventative tips.
Don (aka EQCMCAT).

 

2 1/2" single exhaust based on the stock setup. I only retained the converter that has 2 in and 1 out which acted as my Y-pipe. The other converter I deleted.

 

One has to be careful about primary tube size as well. Anything above an inch and 5/8 is too much for an engine not screaming in rpms. For a 302, 1.5 inch primaries is plenty for a truck and 1.625 for a 351 I would wager.