Cold air intake and exhaust

[Deweydog12]

Hi guys im new to this forum. I have a 1998 ford ranger 4.0 i bought recently and have considered buying a cold air intake and/or an exhaust. Are they worth buying? What HP gain could I expect? Thanks in advance.

 

[CurtisP87]

Just buy a K&N filter to go in your stock airbox, it'll stay way cleaner. Then spend all the money you saved from not buying some silly cone filter, and buy a good muffler, have an exhaust shop bend new tubing from headers back, and you're in the money. HP gains will vary, you'd have to put it on a dyno before/after to get a real idea...perhaps someone with more knowledge will chime in about pipe diameter. Its a common misconception that bigger pipes = more hp, but I don't know enough to give you the details of how that's not true...maybe look into replacing the cast iron heads with aluminum. You'll lose a good bit of weight, and they allow for better flow.

 

[shane96ranger]

Your truck came with a cold air intake from the factory. Going with an aftermarket replacement air filter such as a K&N, Accel Kool Blue, or Fram Air Hog may give you an increase of 2 or 3 horsepower - but not much.

 

[adsm08]

Your truck came with a cold air intake from the factory. Going with an aftermarket replacement air filter such as a K&N, Accel Kool Blue, or Fram Air Hog may give you an increase of 2 or 3 horsepower - but not much.

Or it may give you a loss of 10 to 15. Depends on the weather.


The exhaust flow is helped along my a scavenging effect. The different pulses from the different cylinders help to draw each other down the line by creating a sort of venturi effect. Too small a pipe diameter will make the engine have to push harder to make the exhaust flow by causing a restriction and not letting the gas move efficiently. Too large a pipe will hurt engine performance by negating the scavenging because the pulses aren't large enough (in terms of air volume) to help draw the next one out.

 

[bigtruck94]

A cold air intake on the other hand is worthless. I tried one on mine, I am never going back to one again. All it did was made a whistle. Instead, go onto MBRP and order a cat back exhaust. My friend has one on his and it sounds freaking awesome!

So no to cold air intake. No tuners and no throttle body spacers.

Yes to Exhaust systems and maybe a SAS.

 

[Deweydog12]

Thanks guys. I think im going to put dual cat back exhaust on it. Also the dealership put a 2 inch single exhaust on it. I looked underneath of it and the exhaust is necked down from 2.5 inches to 2. This may be causing some restriction.

 

[Andy D]

The colder the air the denser it is, so you get more O2 per volume. The exhaust on the Rat was a pipe where the cat should have been , then there was an intermediate pipe cobbled into a rotten muffler. I grafted in a 2 1/2 " cat from my waggy, then I re-used the even more hacked intermediate pipe into a new Walker OEM muffler. Pure fricken luck , The system goes from a 3" pipe at the Y pipe flange to a muffler outlet of 2". It is mellow and I have it bailing wired to the body high and tight. I can chirp the tires in 2nd gear, and it gets 21 MPG , so it hasn't hurt performance.

 

[hank857]

as you can see people vary with what they think on the subject. True you do not need a fancy air intake, but if you want to get some gain you will actually need both. I have a 94 with the 4.0, drove it on hwy 150 miles rt daily for almost 10 years. now has 300000+ on it, no real major work, just mainly FW&T items. I run a ca from some out fit that had it for a 97 but it worked on mine, asked them about the shroud etc, they told me for highway I would get more than enough airflow so the shroud not needed. I had a guy bend up a 2 1/4 pipe system from the Y back. he also installed a free flow cat, and a magnaflow muffler. He said you can only go up 25% over stock to get benefits. anyhow that was about 200000 ago, systems still work, still get around 15-16 in town and 20-21 on highway at 70-75mph.

Did I see/feel any seat of pants increase? Just a little, but I tell ya it does run better and I also run 265 70 15 tires now from what ever the 14's were. There are some throttle bodies out there that are bigger, but cause use of more fuel so there is a trade off. Just do what you would like it is the best I can tell ya.

 

[Deweydog12]

Are there any programmers that would plug into my truck or flash the ECU. Ive seen ones from 10-20 hp but dont actually know if they work.

 

[LIMA BEAN]

Remember too that your stock intake sucks air in pretty low so if you are going to goof around in water you need to raise that point or you will hydro lock it and toast an engine.

 

[pintobobster]

just adding a bump to this thread

cold air intake multi-tested

https://www.youtube.com/watch?v=gCi2yo4UqPI

 

[Blown]

1.7%!

The gains would be larger if the vehicle was not already set-up with a cold air intake as are Rangers.