Power Gains

[Gotta_gofast]

An electric fan will provide a miniscule gain.

An upgraded exhaust will most likely allow you to pick up 2-3hp on the top end, nothing to be felt or seen at cruising speed.

An intake will only be beneficial when the engine is requiring a lot more air than stock. A vacuum gauge in the manifold will show "0" inches of vacuum with the throttle plate horizontal to the throttle body. This means the engine is consuming as much air as it possibly can (there is no restriction). Adding 6" dia. tubing, a 200mm MAF sensor, and a 4000cfm filter won't give any more power than the stock setup. And you need to watch out for CAI kits that do not seal the filter. A heat divider will not protect the filter from engine bay heat.

Intake and exhaust will make a difference if you are supercharging/turbocharging your vehicle. But on a stock engine I will bet a 5-6hp difference at peak rpm on a chassis dyno. Not worth it. For a little more investment, you can regear!

 

[Tulsa Time]

Gator is correct. Better flowing exhaust will evacuate the cylinders better allowing more air in. Also a better flowing intake will allow more air in. More air in allows the engine to efficiently burn more fuel (not to be confused with fuel efficiency). The MAF sensor will signal the computer that more air is entering the engine and, even with a stock tune, the computer will add fuel (As previously stated, it take a few miles for the lookup tables to adjust). This will make more power.
It is the same reason racers add turbos, blowers or nitrous, just to a much lesser degree. More air plus more fuel (assuming a correct air fuel ratio) equals more power.
Conversely, I am astounded at how many people will spend $500- $600 for a 10 - 15 hp increase. I am old school. We used to be able to buy an intake manifold, carb, headers and dual exhaust for about $350. (I know, I'm old) These days the dollar per horsepower value just isn't there in my opinion. If it were my truck, I’d spend the money on gears. You won't gain "horsepower" but the performance improvement will be much more noticeable than with intake, exhaust and a tune.

 

[Gotta_gofast]

Gator is correct. Better flowing exhaust will evacuate the cylinders better allowing more air in. Also a better flowing intake will allow more air in. More air in allows the engine to efficiently burn more fuel (not to be confused with fuel efficiency). The MAF sensor will signal the computer that more air is entering the engine and, even with a stock tune, the computer will add fuel (As previously stated, it take a few miles for the lookup tables to adjust). This will make more power.
It is the same reason racers add turbos, blowers or nitrous, just to a much lesser degree. More air plus more fuel (assuming a correct air fuel ratio) equals more power.
Conversely, I am astounded at how many people will spend $500- $600 for a 10 - 15 hp increase. I am old school. We used to be able to buy an intake manifold, carb, headers and dual exhaust for about $350. (I know, I'm old) These days the dollar per horsepower value just isn't there in my opinion. If it were my truck, I’d spend the money on gears. You won't gain "horsepower" but the performance improvement will be much more noticeable than with intake, exhaust and a tune.

How does a cold air intake create "more air in"? I can rig a sewer pipe with 20" diameter inlet to my throttle body and it won't create more power than the stock intake. Ford designed the factory intake for the 4.0L V6. It draws ambient outside air (as dense as you can get without water-to-air intercooler or water/meth injection) and the manifold vacuum is ZERO at wide open throttle. A larger intake has the "capacity" to "support" more power, but if the cylinder is drawing as much air as it possibly can (because we have no manifold vacuum to restrict it) the only way to get more air through the engine is to

1 increase the size of the cylinder
2 modify the valve events and/or cylinder head ports to improve volumetric efficiency
3 use a device that physically forces more air into the engine (super/turbo/nitrous)

In short a 4.0L SOHC engine with an assumed 80%VE will move 332cfm per minute at 5500rpm. If the factory intake allows 332cfm of air per minute to pass through it while reading "0" on a vacuum gauge, we can assume there is no restriction. Should you find a dirty filter or a loose throttle cable, the vacuum gauge at WOT might read slightly from "0", maybe 1 or 2 inches. THIS is a restriction. In this event, a higher flow intake (or fixing the problem) will yield better results.

 

[Tulsa Time]

Please re-read my statement (which you quoted). The only thing I said about an intake is:

a better flowing intake will allow more air in

I was speaking in general terms. The key word is ALLOW. I said nothing of any specific engines ability to maximize that flow.
I can't speak specifically on the 4.0 (or any other Ranger motor) since I have never modified one. To me it's not worth the effort or expense. I can, however, speak on theory since I have been into hot rods and engine performance for about 30 years.

 

[Gotta_gofast]

It was more of a general statement to those who believe adding an intake that supports more volume of air will increase the power in an engine that draws a fixed volume of air (in which the factory intake supports also)

When you deal with performance engines, this is an entirely different story. If I alter my valve events so that both intake/exhaust valves stay open longer, increase overlap to promote scavenging, and increase the rate of lift I can expect to move a lot more air (because the engine will have a higher VE at a higher rpm). Ford did NOT account for this and concequently your intake is now a restriction.

The beauty of fuel injection is that it allows us to create maps and sequences to interpret all the inputs of the engine's sensors. Now we have the best of fuel economy (13.5:1+ AFR at cruise) and safe WOT conditions (12.5:1ish NA or 11.5:1ish FI) and yet allow engine timing to change depending on load and IAT. When dealing with carbureted V8s for instance, a 4barrel carb ontop of a new manifold has effectively changed the path at which the air enters the cylinder (by tuning the reversion waves of the intake to cram more air/fuel in at a given RPM). A new performance carburetor designed for AFR orientated for performance will require a different amount of fuel/metering than an "economy" carb. So in the old muscle cars, it really was beneficial!

To the OP, your limiting factor is the cylinder heads and camshaft (your 99 has the OHV 4.0L). Comp cams offers a 410 series and 422 series camshaft (I suggest 410 for all around power increase) and have your heads ported. When my buddy pulled his OHV out for a 2.3 turbo swap, I gazed at his heads and noticed a lot of casting flaws and horrible valve shrouding in the chamber. A decent head port and a performance valve job will give the best gains to allow your 4.0L to breath better. Then headers, intake, exhaust and a good tune will REALLY shine.

...but do the gears first! lol

 

[Gatorjoe]

One, I never said anything about a cold air intake. I use a high flow intake. Two, I never said anything about increasing the volume of air moving, what a high flow intake really changes is how smoothly air makes it into the engine. Look at a stock airbox on any production car, the hemis, rangers, even my escort, and follow the path air has to take to get into the intake. My 3" hose was fed by a box, where air sits and becomes turbulent, which was fed by a silencer which was smaller than it needed to be.
Smoother air into the engine makes better power and better throttle response. Period.
I do agree with porting and polishing, valve job. But that wasn't the OP's question. The right thing to do is to regear, port the heads, then do intake and exhaust.
But to answer the original question, intake and exhaust=more power in these engines.
I'd really like to see your manifold vacuum gauge showing 0 inches. I don't believe that for a second.
I work with the Chrysler Hemi cars and even those see improvement from a high flow intake. A challenger will see about 15 hp from a highflow intake. If you think these motors come at peak performance from the factory, you need to look around and see what people are doing with every product today. Companies intentionally don't achieve peak performance potential. Ever. Otherwise they'd have to come out with a new motor every year.

 

[Tulsa Time]

One, I never said anything about a cold air intake. I use a high flow intake. Two, I never said anything about increasing the volume of air moving, what a high flow intake really changes is how smoothly air makes it into the engine. Look at a stock airbox on any production car, the hemis, rangers, even my escort, and follow the path air has to take to get into the intake. My 3" hose was fed by a box, where air sits and becomes turbulent, which was fed by a silencer which was smaller than it needed to be.
Smoother air into the engine makes better power and better throttle response. Period.
I do agree with porting and polishing, valve job. But that wasn't the OP's question. The right thing to do is to regear, port the heads, then do intake and exhaust.
But to answer the original question, intake and exhaust=more power in these engines.
I'd really like to see your manifold vacuum gauge showing 0 inches. I don't believe that for a second.
I work with the Chrysler Hemi cars and even those see improvement from a high flow intake. A challenger will see about 15 hp from a highflow intake. If you think these motors come at peak performance from the factory, you need to look around and see what people are doing with every product today. Companies intentionally don't achieve peak performance potential. Ever. Otherwise they'd have to come out with a new motor every year.

Well stated.

 

[Gotta_gofast]

One, I never said anything about a cold air intake. I use a high flow intake. Two, I never said anything about increasing the volume of air moving, what a high flow intake really changes is how smoothly air makes it into the engine. Look at a stock airbox on any production car, the hemis, rangers, even my escort, and follow the path air has to take to get into the intake. My 3" hose was fed by a box, where air sits and becomes turbulent, which was fed by a silencer which was smaller than it needed to be.
Smoother air into the engine makes better power and better throttle response. Period.
I do agree with porting and polishing, valve job. But that wasn't the OP's question. The right thing to do is to regear, port the heads, then do intake and exhaust.
But to answer the original question, intake and exhaust=more power in these engines.
I'd really like to see your manifold vacuum gauge showing 0 inches. I don't believe that for a second.
I work with the Chrysler Hemi cars and even those see improvement from a high flow intake. A challenger will see about 15 hp from a highflow intake. If you think these motors come at peak performance from the factory, you need to look around and see what people are doing with every product today. Companies intentionally don't achieve peak performance potential. Ever. Otherwise they'd have to come out with a new motor every year.

One more reason not to buy a dodge product then. My old 3.0 ranger had a vacuum gauge that read 0 at WOT (even at redline). My current 4.0L ranger showed the same results with the stock intake, and my wifes ford fusion with a 2.3 has yet the same results.

 

[Gatorjoe]

Once again, I'm not arguing that you're reading 0 at WOT. Though I'll believe it when I see it. But smoother air in=better atomization=better power.

 

[Gotta_gofast]

I'd really like to see your manifold vacuum gauge showing 0 inches. I don't believe that for a second.

Yea you are.

In a fuel injected vehicle, there is no fuel atomization until a few inches before the intake valve on our sequential port fuel injection. The hydrogen, oxygen, carbon dioxide, and any other molecules found in your atmosphere may have been disturbed way down stream (your air filter is separating airflow into hundreds of thousands of different paths through the element yet removing a properly sized filter results in no power increase) yet the air still flows in a uniform direction. I will bet money that a 3mm casting flaw on the short turn radii of your head's intake runner will have a greater effect on volumetric efficiency than a 12mm MAF sample tube in a 70mm MAF housing a few feet away from the intake valve.

Why are your vehicles showing such a gain in power? Every third party dyno comparison I've ever seen comparing stock intake to aftermarket intake ALSO tunes for said intake. When they write a tune for the new intake, they also add a bit more timing and adjust the fuel tables to favor power over economy. I would like to see someone spend half an hour tuning a stock ranger and then install a CAI onto the ranger and spend another half hour dialing in any "changes". I will bet the difference is negligable.

K&N spends lots of cash marketing 10hp gains. I refuse to acknowledge their biased claims. Magazine articles are the same. They ALWAYS favor the companies who advertise. I think magazine articles are just as biased therefore I don't take them too seriously.

 

[Gatorjoe]

You say you're seeing 0 at WOT... Is that under load? Are you seeing 0 continuously or does it come back?

 

[Gatorjoe]

Yea you are.

In a fuel injected vehicle, there is no fuel atomization until a few inches before the intake valve on our sequential port fuel injection. The hydrogen, oxygen, carbon dioxide, and any other molecules found in your atmosphere may have been disturbed way down stream (your air filter is separating airflow into hundreds of thousands of different paths through the element yet removing a properly sized filter results in no power increase) yet the air still flows in a uniform direction. I will bet money that a 3mm casting flaw on the short turn radii of your head's intake runner will have a greater effect on volumetric efficiency than a 12mm MAF sample tube in a 70mm MAF housing a few feet away from the intake valve.

Why are your vehicles showing such a gain in power? Every third party dyno comparison I've ever seen comparing stock intake to aftermarket intake ALSO tunes for said intake. When they write a tune for the new intake, they also add a bit more timing and adjust the fuel tables to favor power over economy. I would like to see someone spend half an hour tuning a stock ranger and then install a CAI onto the ranger and spend another half hour dialing in any "changes". I will bet the difference is negligable.

K&N spends lots of cash marketing 10hp gains. I refuse to acknowledge their biased claims. Magazine articles are the same. They ALWAYS favor the companies who advertise. I think magazine articles are just as biased therefore I don't take them too seriously.

You pay for the dyno sessions... I'll take my truck to the dyno with stock airbox on it. Run it, put the high flow back on. Drive it 100 miles to let the computer learn, run it again. I'll bet there's a 6-10 hp increase there. I don't have a fancy k&n system. I run a MAF housing adapter with a Spectre cone filter, hooked to the stock air hose. I'll also bet that if we test air temp going in to the filter, it's lower with my setup than the stock airbox.

 

[Gotta_gofast]

Now I know you're full of it. You're telling me sticking a cone filter in the engine bay will pull cooler air than the factory intake which ducts into right behind the headlight drawing in actual ambient tempurature from outside air???

I had similar arguements before, so before I took it upon myself to set a few scangauge settings with my Volant intake (the only true aftermarket intake that closes the filter from engine heat and ducts to the fenderwell and behind the headlight). I don't remember the exact numbers, but sitting still it was 50+ degrees hotter with the lid off of the box exposing the filter element vs. being sealed and driving it was still 10-15 degrees hotter. It was in the fall and I believe weather temp to be in the 40s. Why did I invest in an aftermarket intake? Well I'm in the process of supercharging the truck so I need "more than stock" intake. Whats more, is our 5R55E transmission has a ""torque into torque converter" sensor that I can monitor with my SCII. Both tests were done on the same hill starting in the same place with the trans selected in "2". I don't know how accurate the torque value of the SCII is compared to true torque at the flywheel, but these numbers are comparing to EACH OTHER. The SCII was set up to record peak numbers (so I didn't have to stare at the gauge while driving) and reported 230 and 232 peak with the filter enclosed. With the filter exposed and open reported 227 and 227lbs.

I know you didn't and will never pick up 6-10hp from simply running an adapter to a cone filter. In fact, I bet you lost 6-10hp.

Do you really think if Ford could pick up 6-10hp from a simple MAF adaptor and filter change that they would have ignored this? REALLY? Horsepower is one of the selling points of a vehicle, why would Ford choose to choke down an engine when it would be cheaper and produce more horsepower to design a simple adapter and cone vs a molded box with specific openings to the outside world?

 

[Beanmachine7000]

You pay for the dyno sessions... I'll take my truck to the dyno with stock airbox on it. Run it, put the high flow back on. Drive it 100 miles to let the computer learn, run it again. I'll bet there's a 6-10 hp increase there. I don't have a fancy k&n system. I run a MAF housing adapter with a Spectre cone filter, hooked to the stock air hose. I'll also bet that if we test air temp going in to the filter, it's lower with my setup than the stock airbox.

Now I know you're full of it. You're telling me sticking a cone filter in the engine bay will pull cooler air than the factory intake which ducts into right behind the headlight drawing in actual ambient tempurature from outside air???

I had similar arguements before, so before I took it upon myself to set a few scangauge settings with my Volant intake (the only true aftermarket intake that closes the filter from engine heat and ducts to the fenderwell and behind the headlight). I don't remember the exact numbers, but sitting still it was 50+ degrees hotter with the lid off of the box exposing the filter element vs. being sealed and driving it was still 10-15 degrees hotter. It was in the fall and I believe weather temp to be in the 40s. Why did I invest in an aftermarket intake? Well I'm in the process of supercharging the truck so I need "more than stock" intake. Whats more, is our 5R55E transmission has a ""torque into torque converter" sensor that I can monitor with my SCII. Both tests were done on the same hill starting in the same place with the trans selected in "2". I don't know how accurate the torque value of the SCII is compared to true torque at the flywheel, but these numbers are comparing to EACH OTHER. The SCII was set up to record peak numbers (so I didn't have to stare at the gauge while driving) and reported 230 and 232 peak with the filter enclosed. With the filter exposed and open reported 227 and 227lbs.

I know you didn't and will never pick up 6-10hp from simply running an adapter to a cone filter. In fact, I bet you lost 6-10hp.

Do you really think if Ford could pick up 6-10hp from a simple MAF adaptor and filter change that they would have ignored this? REALLY? Horsepower is one of the selling points of a vehicle, why would Ford choose to choke down an engine when it would be cheaper and produce more horsepower to design a simple adapter and cone vs a molded box with specific openings to the outside world?

^^ He's right... There's been enough of these threads this stuff shouldn't even come up any more...

 

[Dirmaid]

Do you really think if Ford could pick up 6-10hp from a simple MAF adaptor and filter change that they would have ignored this? REALLY? Horsepower is one of the selling points of a vehicle, why would Ford choose to choke down an engine when it would be cheaper and produce more horsepower to design a simple adapter and cone vs a molded box with specific openings to the outside world?

money. 5 bucks saved in materials on a million trucks in 5 million bucks they never spent. it wouldnt be cheaper to make a cone filter assembly when there is A LOT more surface area (meaning more material) on a cone filter vs the standard filter.

i will agree that 400 bucks for a supposed 10 horse increase is absolutely rediculous. IMHO, where ford went wrong with their intake design was they didnt put a supercharger on ever ranger stock