Hi All

When I looked under my 2001 3L V6 Ranger. I find a CAT. Then I find I think 2 or more behind it closer to the engine. That have sensors with them.

My question is about the heavy low one. Is it needed? Not nice looking. Doesn't even try to hide. To me it is in the way. Not to mention very ugly. Even a new one would be ugly. It makes lots of heat. So raising it is a bad idea. The engine has the other CAT's.
So does it really need the big ugly one to pass emitions? There isn't a sensor after it. So the computer doesn't know about it as far as I know. Nothing plugged into it. Just there and not pretty.

I'm open to thoughts facts opinions and others that feel this way. If you took it off? Did it pass emitions? I have a big enough muffler now to tame any noise it was there to stop. Any help please.

Jim

 

If the Cat gets hot then it is burning hydrocarbons so would be needed for emissions requirements.

You may want to look at newer Ranger exhaust systems, the Cats, the ones closer to the engine, there may be newer ones that work better than 2001 had, so 3rd Cat wasn't needed on newer model 3.0l Rangers.

i.e. Ford may have needed to add that 3rd one to meet emissions requirements that year in certain areas

No car maker wants to add more parts, just like no one wants to pay more taxes, lol.

But requirements to sell a vehicle in certain areas are just that requirements, whether it is seat belts, air bags or emissions, you want to stay in business you have to meet those requirements.

 

RonD

Thank you. I wasn't trying to not be to emission standards. It is a cosmetic thing. As long as it is still running. I'm not going to buy a new CAT. I had to make a new exhuast when I got it. The tailpipe was like the size of a good cigar. When I looked at the joining at the CAT. I saw 2 and 1/2 pipe. So I fixed that. Then I added a muffler. Sounds better and excellerates better.

I just thought that the other CATs could meet the current Emissions alone. Depending on my future. This might be a spare truck. Right now it is my one and only.

The other night I downloaded Torque Pro on my Android tablet. I just need the blue tooth plugin. I can't wait to try the heads up display on the windshield. Thats going to be fun. It might also give me better knowledge as to what that truck needs for Emissions. It has the emission test in it. Lots of other apps to do even more stuff as well.

Thank you again.
Merry Christmas
Jim

 

Merry Xmas

Rangers have tuned exhausts so surprising any change after Cats would matter to performance, sound yes, for sure, bigger pipe makes lower note, just like on pipe organs.

Larger pipes at the heads are bad though, you lose the tune.

 

RonD

There was a skinny pipe going back from the CAT when I got it. So I just replaced it with 2 and 1/2 inch pipe like from the engine. I figured it was factory like that. Ran it without a muffler for a while. Wasn't bad loud or good loud. Spoke to my nephew the Diesel mechanic. He showed me his old truck. He said he did that when he got his truck. He told me the pistons topped out or something like that. Now it doesn't run as well. Not at all as well. He says you do need a little back pressure to help in exchange with the air enter and exit. The pressure makes it easier.

So.. Not real happy I got a muffler. Doesn't sound bad because it is all up under the bed. I don't have a tail pipe coming out any side or the back. I like it like that. There is a down pipe on the muffler. So the sound goes down and all around under the bed to make a lower note that is nice.

That low hanging CAT just kills me. At first it didn't matter. Now its like really. Why. Because I look at everything all the time. I'm nuts like that.

Really don't want to take the exhaust manifold off for headers. I would if I dumped a V8 in it. At first that sounds crazy. Then it doesn't. It won't change the MPG any. Oil change would be expensive if I didn't do it. More than likely I will have somebody do it for me. A store. I know its easy. Its just me.

In the spring I'm going to get an angled pipe to put after the CAT. That will put all of the exhaust up above the bottom of the truck. Except that CAT. That might have been part of California Emission standards. Or PA. They both have different standards.

Not happy with my fog light set up. So that all comes down in the spring as well. Plus all the other stuff I already have parts for. Didn't get enough nice weather. So I have new fuel filter. New dashlights. Need to tighten the shifter. Need to align the shift indicator. All that I have. Just don't have a nice place to do it in.

Good night
Jim

 

No 4-stroke engine runs better with any back pressure, 2-stokes do and need it.

That Myth came from people installing larger pipes at the heads.

If you have correct size pipes at the heads then exhaust flow is not restricted and you get a good velocity in that smaller pipe(velocity is the key), and then if you dump that smaller pipe into a larger pipe, the collector, the velocity of the exhaust flow will create a low pressure as it passes thru the collector, and the other smaller pipes also connected to that collector get that pull of the lower pressure.
The length of the smaller pipes and size of the collector will determine when the lowest pressure will occur in the RPM band.
This is exhaust tuning 101, but very basic info

Most stock exhausts are tuned for mid range RPMs, Rangers are.
After market "headers" are usually tuned for lower RPM range
Racing header higher RPM range.

The low pressure gets to -3 to -4psi at the exhaust valves during peak for the tune range, I have read of some racing headers that have gotten to -7psi.
What this does is to pull exhaust out of the cylinder when exhaust valve opens so pistons/crank don't lose as much power pushing it out.
And you feel that as extra power
Tuned exhaust is also called a scavenging exhaust.

Where the Back Pressure myth came from is people removing stock exhaust manifolds and installing "Free Flow" manifolds, larger pipes basically.
So they lost all the velocity and so any lower pressure.
When they went out for the test drive...................
"Hey, WTF!!!, I lost power?!?!"
"This engine must need back pressure"-The start of the Myth
The result was correct, you will lose power if you remove tuned exhaust for untuned, but conclusion was wrong.
Size of head pipe needs to be correct for the engine/cylinder size, to get good velocity but no restriction.

On dual exhaust they will add "X" or "H" crossover pipes to scavenge even a little more power, the exhaust pulses from one bank pulls exhaust out of the other bank on the crossover, and visa versa

So don't you believe it, no 4-stroke engine needs or wants Back Pressure

 

RonD

I believe that. Probably something else went wrong with the nefews truck. Or it was on its way to it after he got it. After all the diesel engine works a little different than the gas engine.

Then I am lost in my experience. When I put the muffler on it did excellerate better. I don't have headers. I have the Ford stock stuff from the engine to the big CAT.

The portion I altered is after the big CAT. Or term CAT back.

I did watch a video about back pressure and trucks. It even mentioned scavenging to get the air.

I haven't got the blue tooth thing. I have seen a video that showed zero to a few Psi is in back pressure on a car. Then I saw a car rev with little to very little PSI. As being the engine working with all stock pipes.

What I am understanding is all scavaging for air is done before the big CAT. So after the big CAT it sounds like it is open to your imagination.

Now I'm not sure what to do. Remove muffler or not?

Jim

 

As long as you use same diameter or larger from Cat back you won't effect a tuned exhaust.

May be a misunderstanding here.
A 4-stroke engine doesn't "need" back pressure, it has back pressure, but if you use a tuned exhaust you can create a velocity that will create negative pressure at the exhaust valves in specific RPM range.

If you just put on larger pipes at the heads you will have no back pressure but you will loose the ability to create the low pressure to get scavenged power, hence the power loss people experience when doing that and the Myth of engine "needing" back pressure.

Even "strait pipe" exhausts can be tuned, i.e. drag racers, the diameter and length of the pipe creates a negative pressure in the pipe as exhaust pulse leaves the end of the pipe, so at certain RPM range exhaust is pulled out, leaving more power in the crank for rear wheels.
This gives that engine an edge, in specific RPM range, over an engine just using large diameter pipes, but that engine would also have some back pressure at other RPMs, unneeded but there none the less.

So the Myth is just an incorrect conclusion of the results of removing a tuned exhaust

 

RonD

Thank you. I was only adjusting the size of the pipe after the last CAT. Not from the engine.

I would imagine removing the manifold for headers that are the right size could help the engine in some areas.

I found I can get a CAT for 70 at autozone. Nicer weather and I will replace the ugly CAT with that. At the same time I will change the fuel filter. I will also clean the MAF (those oxygen things after the air filter).

I also put together a better pipe set up for the exhaust. I will be replacing the ugly CAT with a pretty one. I will be adding a resonator. Then more pipe and a Cherry bomb at the end. This design will also make everything after the CAT easy to hide highier in the frame.

Not trying to make a race truck. Only interest is to make the Engine happy. That way I can make this little guy last a long time. So later in life it can be my spare truck. Even the big muffler I put on it is covered and sealed from rust. As well as the pipes I am using. Just making a set up that will last.

Spring Is when a lot will happen making this truck last longer. With help frame sanding and sealing against rust. Engine cleaning. The entire compartment. Seeing what needs to be replaced. Also painting the manifold and engine parts with heat proof paint. Big task. I started some of this. Not complete. Never did all this before. I just hope it will make it last. I don't think resale will be to high. So preservation is the main idea. Also making those ugly parts look cool and clean.

Well the project section in here. I guess I do have a project. Trying to un-rust and make last for many years.

I can't replace anything right now. It is way to cold. Also a money thing. Getting the bluetooth thing I can use torque on my tablet to understand how the other systems work together. I found a free app for Android phones or tablet. Called TSX. It is in the play store. With the bluetooth thing you can get rid of rev limitor and MPH limitor. Or you can program them the way you want. Also does sport tuning. All for the price of a bluetooth plug in. There are many things besides torque that play with the truck. I can't wait to try the heads up display at night. After you find torque you can find the others. It allows you to also tune the engine like the flashpaq does.

Thank you for explaining the back pressure myth. Because in the future that low hanging CAT will need to be removed. I don't want to raise the truck. In the future it might be parked in high grass. That CAT is how trucks catch on fire.

Merry Christmas and Happy New Year.
Jim

 

Sounds like a good plan.


One thing you can do that frees up horse power, gets you better MPG and can make engine last longer, is........................

Switching over to an Electric radiator fan.
The mechanical fan runs all the time, so always a drain on horse power and MPG
Electric fan is only on when needed for cooling, i.e. when stopped or driving slowly, air through rad at above 40MPH will usually cause E-fan temp sensor to shut it off since air thru rad is enough to get maximum cooling.

Not an expensive DIY job, especially if you use junkyard fan(s) and relays
All FWD cars use E-fans so parts are plentiful

 

Well yes.

Because the fan is part of the belt system. Still can't get my chirping to go away. Hit that belt with the spray many times. Not going to do that anymore. The stuff in that conditioner is all alcohol. Or in the same class. Still kills me a belt that new sounds like a dead one. The white lettering is so bright on it. It is shiny new. Even before I hit it with the conditioner. Oh well.

As far as a junk yard. I have yet to see one in ohio. I need to check online for one. So the mechanical fan will never stop when truck is on? Kind of a weird design. Yet I just had a thought. Could air from the fan be redirected into the air filter box? So is to have more air. Wait that might mess up the air fuel ratio when driving. Or might it not?

Still have outside air mix with it. Just have a small amount of the fan air enter the box. Still letting other air through. In basics the air box MOD of taking off the baffle is to get more air. What if it was the fans air helping? Times it might be iffy are when you aren't moving. I can almost bet some of that air makes it in there when not moving.

Since the fan is on when the truck is on. There must be sensors that correct for that in the mass airflow sensor. Kind of like a big breeze hitting the truck. Yet still it might just have extra tollerences built in for that reason. Or it might not even be that accurate to care.

My theory here is the fan must be always moving for a reason. Because there are 2 radiators there. The transmistion fluid radiator. It is there working all the time. Even if you aren't trying to pull that heavy load. That was the leak on my trailblazer I could not get fixed. Mechanics couldn't stop it. 300 dollars later. New RAD in for it to still leak with all new lines.

This just came to me. I'm asking you about effects. I'm still learning. I think you have a lot of engine and mechanical experience. I just feel that if its not needed in one area it could be used in another area to a benifit.

Idea is different than a ram air set up. Only using more air when moving with gravity feed. Yet to feed more air in mechanically. I know the emitions people don't like extra air going to the engine for some reason. Because alterations to add air flow to the engine are considered illegal modifications.

I hope to get the blur tooth adapter tomorrow. That can show me how these sensors change while not moving. Also if I add more air while still parked. I will be able to see fuel air mix ratios before and after. Then I say whats the worst that could happen? Might be fun if I get the chance. Also what do you think about the idea? Danger or Not a danger?

Jim

 

Fan belt slipping "glazes" the pulleys, glazing creates very smooth surface on pulley
So replacing the fan belt won't always get rid of the chirping noise

If you had fan belt noise because of stretched belt then it "glazed" the pulleys every time you heard the noise.
So new belt will still slip on the glazed part of the pulleys.

Best practice is to use Emory cloth to ruff up all the pulleys before installing new belt, or ruff up and paint pulleys.

Belts slip because they loose traction/friction on the pulley surface, "belt treatment" drys belt surface to give it a better grip temporarily, not a fix.

Now some belt layouts are prone to slipping, not enough belt wrap(surface contact) for the resistance of the device the pulley is powering, i..e power steering pump, AC, alternator, ect....
Or even crank pulley if there is not enough "wrap" for combined resistance of all accessories.

Not much you can do about that, but if you ruff up pulleys to give new belt the best grip possible then you have done all you can do.

And could be an accessory bearing is starting to wear out, so slight increase in resistance, just enough to get you the chip now and then.


Mechanical fan is just the simplest, cheapest, way to pull air thru a radiator when vehicle is not moving.
When engines were mounted sideways in engine bay, transverse mounting, there was no option except e-fans.
And surprise.....these vehicle got better MPG

Fan clutches were added to reduce fan noise, after cold start the fan clutch opens so fan blades don't pull in as much air, you may hear this when engine starts, a "whirring noise" and then it diminishes, thats the engaged fan clutch spinning the fan at full speed, then releasing it because radiator is cold.
Fan clutch has a bi-metal spring on the front, when it is cold fan spins free, after first startup, then as radiator's center area warms up it warms up the bi-metal spring, this slowly engages the clutch(fluid coupler) and fan starts to spin at engine RPM speed, to move more air to cool radiator when stopped or driving slowly.
The fan clutch does help reduce HP and MPG loss BUT...........only when engine/radiator is cold, lol, so not really much help, unless you don't drive more than 5 minutes at a time

E-fans work fine with automatics and Air conditioned vehicles, i.e. all the transverse mounted engine vehicles on the road today, millions and millions.

Mechanical fans are used because they are simpler and cheaper, that's the only reason


Ram Air was introduced by Pontiac, it was first Stock Cold Air Intake(CIA).
Looks cool and CAI does help for power.
BUT........a road vehicle simply can not achieve the speed needed for the "ram air" part to do any "boost" of air into the engine.
Airplane engines did take advantage of that, which is where Pontiac got the idea, lol

So no, on Ram air, outside of the looks, which is very very cool IMO.

All Fuel injected engines have CAI, so all Ranger have it as Stock part of vehicle.

Turbo or Super chargers are the only way to boost/increase the amount of air that an engine can use.
Engine displacement is the amount of air it can use without boost.
So a 2.0L engine can use 2 Liters of air every 2 RPM at full throttle
A 5.0l engine can use 5 Liters of air every 2 RPM at full throttle

Air:fuel ratio for gasoline is 14.7:1 this is a WEIGHT ratio not volume, so 14.7 POUNDS of air to 1 POUND of gasoline.

A 5.0l engine has more power than a 2.0l engine because it can pull in more air, simple as that, the more air you can get in the more gasoline you can add so the more power you can release every 2 RPM.

Turbo or Super charging increases the amount of air that can be put into the engine every 2 RPM, so a 2.0l engine with turbo might now have the power of a 2.5l engine, or even 3.0l engine

 

Ok

I'm going to find my metal smoothing paper. Emery board paper. I have a few pulleys that look like mirrors. I can see a big slip there. Never have seen shiny pulleys. I can carefully ruff them up. Take the shine away. Looking at it the shiny side hits the back of the belt. The belt was shiny when it was put on. Hot weather it wasn't a problem. Then as it got cold. It started chirping and screaming like crazy. I don't want to ruff the belt up much. I will get that less shiny very careful. I will take the mirror right off the shiny pulleys. At the same time being careful not to make the surface less round. I see belt hoping off that way.

As I was thinking about re-using the air from the fan. I was thinking like a turbo so to say. I was not expecting to get a turbo that way. I thought maybe the engine could use the extra air to be cooler or just use what it is making anyway.

By your information about air/fuel and the ratio. I see that the only thing I will get from my idea is a lot of work. Also possibly having something in a location that might cause problems in the engine when it comes flying off. So this idea is just as useless as the cone filter set ups. Still not adding anything of use to the engine.

Now I'm waiting for my blue tooth device to come in the mail from walmart. So I will just wait to see then. Muffler thing. I really am going to see the difference. When I do it I will post the video here. Muffler and minus muffler. My head is telling me that any change will be nil in the numbers. Because I'm not starting at the engine with my change. I'm starting after it has been tuned and has scavenge places set. Hence the word tuned exhaust.

Are you working on anything right now?

Thank you. It is nice to learn this stuff. This forum and this truck is helping my health. Thank you
Jim

 

In "cold weather" there is often rain and water on the road so that gets on the belt and pulleys, so if they were marginal when dry they will squeal when wet.

If pulleys are shiny then paint belt surface black, or what ever color you want, paint is a ruff surface.
The belt is a rubber compound so unless damaged it doesn't need any sanding or other treatment.
It's the metal that gets glazed or polished and needs to be ruffed up

People have tried Leaf Blowers as turbos, mind you not very smart people, lol, of course it can't work, very hard to get the kind of air movement you need from leaf blower.

 

I can only imagine a leaf blower added to a Ranger. Now that would be funny. A leaf blower.

I'm not going to redirect the fan. I see to many bad things happening. All with the mounting and such.

Those shiny surfaces will get taken care of. Just so funny. Never saw pulleys that looked like mirrors. Ever truck is different.

Jim