93 F-150 4x4
I dont mean to be the black sheep in the ford family but.... What the h-ll are you guys doing to get all this power out of your engines? Ive never really heard anything bad about these engines, so im confused!
Horse power.....On the freeway im basically floored to keep 70-75. The down side of the hill is my best friend!
Torqe..... We have this huge sand hill around here and i cant get up it. Im not loosing traction just power--even in 4 low. A friend of mine said it doesnt make any sense because he used to run all over that hill in his 300 i6! What gives???? The worst part is that me and my buddy went their to play and brought the video camera. And thats when i found out it didnt have the pull to make it up. I was so ashamed looking at his "Chevy" up their looking down at my poor Ford. And its all on tape.
My truck is sick! any one have any cures? HELP!! Thanks!

 

Ford truck guys to the rescue!!!! Well to tell the truth I don't know exactly what the problem is. However I have a few things in mind you should check. First found out what type of ring and pinion gear your truck has. Make sure to check both differentials. On each differential there should be a metal tag, on this tag is set of numbers. Post those numbers here and I'll tell what you have.

Second is your clutch slipping and how many miles does it have on it?

Next, the two catalytic converters on your truck may be clogged. The only way to get around this problem is to have them replaced. Look into your state's emission laws and see if you can change out those two cats for a single high flow cat. This will make an improvement on your truck's performance.

What size of tires do you have on your truck?

Have you done a tune up recently?

From what you said:
"Horse power.....On the freeway im basically floored to keep 70-75. The down side of the hill is my best friend!"

I have a real gut feeling the cats are clogged and aren't allowing the engine to breath! If you do choose to replace the cats you may also want to look into redoing the whole exhaust system. These inline 6s love to breath and with stock equipment they are choked rather well. Take a look at getting a set of Clifford Performance headers, a high flowing cat, and a good muffler. This will really get your truck to kick like a mule!!! Woo hoo!

 

If you have 4wd I don't think you can have less than a 3.08 gear, and in 4-low you should pull anything the tires can keep traction on without hardly hitting the gas. What paulg says is definitely true, but if you're as cheap as me, just tuning up usually will get you up to snuff. I'm kind of a maintenance fanatic, but replacing filters, plugs, and wires will go a long way. If that doesn't do it, get into your catalytic converter and emission control/eec system. I rent an analyzer, which comes with hookup and operation instructions, and run in 'view' mode while driving and doing the things that have been causing problems. You can see what all your different analyzers and controllers are doing, and see if what they are 'seeing' and doing seems logical. Even if you don't have failure codes you can often find sensors that are reading inaccurately due to simple dirt or corrosion. You can check your cat this way too, if it has excessive backpressure, when you step on the gas( lightly, then hold it steady) you will see your absolute manifold pressure rise quickly as you feel a 'hit' of power and then dog down. I hope I explained that understandably. I generally buy used, solid vehicles with need for a little 'tweaking' for my work trucks just because they're cheaper, and 4.9s are one of the most 'unkillable' engines I've found.

 

I agree with paulg on this one, all except for the Clifford header(sorry paul :P). You're 93 has the dual exhaust manifolds already on it each one is 3 into 1), which perform just as well as any header.

First thing I would do is a thorough tuneup (including compression check), and run a diagnostic test to make sure you don't have a bad sensor somewhere. Trust me, they're evil little devils when it comes to robbing power. If that doesn't cure the problem, check into the cat's and replace if needed. The single performance cat is the way to go if your state allows it.

TrailDawg
1993 F150 2WD
4.9L-Auto
Pro-Comp Stage-2 6" lift
Auburn Pro-Series Diff. w/4.56:1 gears
35x12.50x15 General Grabber MT's

 

Speaking of headers and stuff, i just wanted to know what the difference was between the CP single and dual headers are, as in advantages/disadvantages, and what they'll do for my '82 I6... I'll be doing up my truck within the year, probably gonna sink a few thousand into body and engine...

-Der Meister-

 

[font size="1" color="#FF0000"]LAST EDITED ON 07-Mar-01 AT 05:08 PM (EST)[/font][p]Well to begin with the purpose on any header is to reduce backpressure as much as possible and therefore increase power!!!! No if, ands, or buts about it: BACKPRESSURE KILLS POWER,period!!!!!!!! SOOOO... with that concept in mind, I'm still not sure what the advantages and disadvantages are between CP's single outlet header and dual outlet header. I do believe the two styles of header are for different year/model applications. Installing headers is definitely something you want to do! Here is a weblink explaining why:
http://www.howstuffworks.com/question172.htm

So there Traildawg! thpbhtbhhthththpbpthbptbhtphbpthb! So how did you make the smile/tongue face?!!!?


I installed a set of dual outlet headers on my truck and boy did she like that! WhoaoooO nelly!

1994 Ford F150
300-6
Highly Modified and more to come!

 

Ya mean this one :P

Well I'd tell ya, but then I'd have to kill you and start cutting up your truck for parts. I'm sure you wouldn't want that now would ya :P

TrailDawg
1993 F150 2WD
4.9L-Auto
Pro-Comp Stage-2 6" lift
Auburn Pro-Series Diff. w/4.56:1 gears
35x12.50x15 General Grabber MT's

 

You're cruel man, you're cruel!


1994 Ford F150
300-6
Highly Modified and more to come!

 

Ok, I can't resist......

From that link you gave me, it says:

"In a normal engine, once the exhaust gases exit the cylinder they end up in the exhaust manifold. In a 4-cylinder or 8-cylinder engine there are 4 cylinders using the same manifold. From the manifold the exhaust gases flow into one pipe toward the catalytic converter and the muffler. It turns out that the manifold can be an important source of back pressure because exhaust gases from one cylinder build up pressure in the manifold that affects the next cylinder that uses the manifold.

The idea behind an exhaust header is to eliminate the manifold's back pressure. Instead of a common manifold that all of the cylinders share, each cylinder gets its own exhaust pipe. These pipes come together in a larger pipe called the collector. The individual pipes are cut and bent so that each one is the same length as the others. By making them the same length, it guarantees that each cylinder's exhaust gases arrive in the collector spaced out equally so there is no back pressure generated by the cylinders sharing the collector."

The later exhaust manifolds on the 4.9L (the dual manifold setup) solved this problem. Following the firing order, each consecutive cylinder is on the other manifold, greatly reducing the "flooding" of exhaust gasses into one pipe.

On a further note, I called Cliffords about 6 months ago planning to order a header from them, and they told me I wouldn't really see any gains because I had the dual manifolds and they offered plenty enough flow for the 4.9L.

So pthththththtth!!!!!!!!!! Right back acha :P

Seriously though, I've read several times here on the forum that there's little, if any performance gains when converting from the stock dual manifolds to a header. For me, it just ment I could spend the $300 elsewhere where it could be more beneficial.


TrailDawg
1993 F150 2WD
4.9L-Auto
Pro-Comp Stage-2 6" lift
Auburn Pro-Series Diff. w/4.56:1 gears
35x12.50x15 General Grabber MT's

 

AAHH NUTS!

1994 Ford F150
300-6
Highly Modified and more to come!

 

aah, but what year did they start using the dual manifolds? i'm running an '82, and i think it has single... so headers would probably do me a lot of good...

 

I'm planning on replacing my stock manifold from a set of dual manifolds from a later model truck at the scrap yard.
My big decision will be whether to go with a single or dual exhaust after that.

 

Rabbit, from the offerings I've seen from the aftermarket, everything is either a single 3 inch system, or a single 3 inch to the muffler, then dual 2.5 inch pipes out the back. Which rought you take will mainly depend on what pipe diameter you want to go with. Remember, you're engine does need SOME backpressure

TrailDawg
1993 F150 2WD
4.9L-Auto
Pro-Comp Stage-2 6" lift
Auburn Pro-Series Diff. w/4.56:1 gears
35x12.50x15 General Grabber MT's
http://www.geocities.com/ProjectTrailDawg

 

dermeister:
I am not sure what year Ford changed from a single header to a dual header. I do believe you can use a dual outlet header regardless of the year of your truck! A dual out header would be better than a sing outlet. Go for the headers!

rabbit stu:
Dual exhaust has a problem when installed in small engines. Because a dual exhaust runs cooler(less exhaust flow) it has a tendency to retain more water/humidity which promotes rust. The 300-6 is the in between engine. Also a dual exhaust doesn't sound that good on a 300-6. A single has more grumble/rumble sound. My 6 has gotten a few compliments say "nice v8 or good sounding exhaust man!" I think you will like the single exhaust more than the dual exhaust. Also dual is more expensive.

Many a post here at this website have discussed the ideas behind backpressure. Most people believe you need backpressure to produce torque. I really don't want to start another argument but backpressure does nothing but dampen an engine's performance. An engine gets its torque mainly the length of its stroke. Basically engines with long strokes(3.5" to 4"), such as the Ford 300-6, get their torque from this design. This is the reason why it likes to run low rpms and can haul/tow objects with no problem. The opposite is true, engines with a short stroke can produce more horsepower, hence they can turn more revolutions. This is the reason why little 4 banger engines in tiny japanese cars can produce more horsepower then torque. By applying backpressure to an engine's exhaust, it makes it harder for the engine to expel the exhaust gas. The laws of physics dictates this! Take this example, is it easier to breath through a straw or with your mouth wide open, especially if you running a 5 kilometer run. You don't want to be breathing through a straw!

Here is a weblink that further discusses the misunderstandings behind backpressure:

http://www.howstuffworks.com/question172.htm

I really don't know what the actual flow rates are between the stock exhaust manifolds and the headers Clifford Performance offers. I had several automechanics tell me the stock exhaust manifolds were enough for the 300-6, then also I had other automechanics tell me the engine could greatly benefit from an exhaust header. So I went with a header (dual outlet) and noticed a performance increase. My engine had better acceleration and gas mileage improved by 1/2 a mile per gallon. However I also rebuilt my truck's whole exhaust system, dual outlet headers, into a 3" y-pipe, 3" high flow cat and out to a 2.5" Flowmaster muffler. REDUCE ENGINE BACKPRESSURE BY AS MUCH AS POSSIBLE. Hell call Clifford Performacne and find out for yourselves. If CP says the stock manifolds are enough then go with them. But be warned if you modify the 300-6, such as new intake, K&N FIPK kit, camshaft, new ignition and bigger fuel injectors you will want a header. One of the reasons why I got mine. I have heavily modified my truck but I still have to add 19#/hr injectors and the camshaft I bought for it. My truck will SCREAM when I'm done.

Please don't think I'm trying to rattle traildawgs cage. He could very well be correct on the stock manifolds, but if you want to modify you truck's engine, get headers. I don't agree with his idea on backpressure though. Hey this is the good ole USA. More power to ya if you have the facts to back up your ideas!




Good luck gentlemen!!

1994 Ford F150
300-6
Highly Modified and more to come!

 

Thanks guys.

I'm just starting on my modifications so I'll probably be going with the dual manifolds and a single exhaust. (The cheapest route) This will leave me more money for other mods.

I'll think about headers some time in the future when I've got more money and more time to think about it.