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Discussion Starter #1
I have a 2.5L on a 95 and I was thinking about letting my little engine breathe better. I've been looking into spacers and intakes, i want to get both. Any suggestions?
 

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Yup, just get a 4.0 throttle body and swap it, did mine pick-up a few hp. Gonna port match the intaake to the TB one of these days too. Just google 2.5 to 4.0 TB swap and you'll get a ton of pages. Or go to WWW.4bangerJP.com.
 

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Spacers and intakes wont do anything.

I had both on my Jeep from the PO. Removed them both, sold them for $150 and everything is the same. No change whatsoever.

Jeep 2.5l use fuel injection, not throttle body injection. Youre "throttle body" you are enlarging only lets in air, 2.5 only needs so much you can force feed it more and expect horsepower or something :rofl:
 

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Discussion Starter #4
you put throttle body in quotations like its imaginary. And increased airflow still allows for better fuel injection.More air allows more fuel to burn making more energy producing more power. Those two product lets more air flow into the engine. Are you saying theres no amount of added airflow thatll benefit the 2.5 in anyway?
 

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I put an AEM brute force cold air in my TJ and it gave me another mpg and a little better pick-up as well as a meaner sound. IMO it was well worth the money.
 

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An air intake, 4.0 throttle body, and throttle body spacer have been proven on a dyno to gain somewhere around 6-8hp, ontop of gaining acceleration. Removing them is doing quite the opposite.
 

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Xpress said:
An air intake, 4.0 throttle body, and throttle body spacer have been proven on a dyno to gain somewhere around 6-8hp, ontop of gaining acceleration. Removing them is doing quite the opposite.
Tell me if you felt the difference, if you did it was a placebo feeling because you want to think it changed it a bunch.

An engine can only use so much air, as it only injects so much fuel. For there to be a great combustion there has to be a ratio of fuel to air. Unless you tune, or advance the timing of the spark in the engine you wont use anymore air then the stock intake provides. Coming from someone who has had them, and removed them I feel I know if there was a difference and there was none. And again, my CAI let more dirt through, a spacer does nothing if anything let more debris and hot air in.
 

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With fuel injection you have a mass air sensor so if a cold air intake allows more air in then then the injectors can also add more fuel while keeping air to fuel mixtures the same. The "cold" portion of a cold air intake is actually very important, the colder the air going to your engine the better the fuel can atomize resulting in a more efficient burn of the fuel resulting in more power and better mpg.
 

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With fuel injection you have a mass air sensor so if a cold air intake allows more air in then then the injectors can also add more fuel while keeping air to fuel mixtures the same. The "cold" portion of a cold air intake is actually very important, the colder the air going to your engine the better the fuel can atomize resulting in a more efficient burn of the fuel resulting in more power and better mpg.
I bet you could take a thermometer to the "cool" side of the intake/shield and then the engine side...and there wouldnt be much difference. I also have a CAI and didnt notice anything other than a change in sound. I put it on back when I was new to jeeps and didnt know any better. I really wish I coulda saved myself a couple hundred dollars lol.
 

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Spacers and intakes wont do anything.

Jeep 2.5l use fuel injection, not throttle body injection.
X2. This was a constant on going debate with the TJs. If you want more response from your 2.5, get an exhaust header, freeflow exhaust, replace manual fan with an electric fan(frees up horsepower), regear, get a turbo kit or never use the 5th gear. In reference to the "cold air" intake, it's actually more of a hot air intake unless you have a ram air induction scoop directly over your cold air intake
 

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Discussion Starter #11
I have the exhaust, getting new headers. I'm gunna get the intake and spacer anyway I was asking if anyone had brand suggestions
 

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I have the exhaust, getting new headers. I'm gunna get the intake and spacer anyway I was asking if anyone had brand suggestions
Airaid is popular for both intake and spacer. I personally like S&B filters, but I don't think they make spacers.
 

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Tell me if you felt the difference, if you did it was a placebo feeling because you want to think it changed it a bunch.

An engine can only use so much air, as it only injects so much fuel. For there to be a great combustion there has to be a ratio of fuel to air. Unless you tune, or advance the timing of the spark in the engine you wont use anymore air then the stock intake provides. Coming from someone who has had them, and removed them I feel I know if there was a difference and there was none. And again, my CAI let more dirt through, a spacer does nothing if anything let more debris and hot air in.
That's 6-8hp on dyno sheets. If I can find them I will post them, it's adding horsepower. There's no placebo effect to dynomometer results, it's telling you the FACTS as they are. You're just going to arrogantly say that opening up the intake and exhaust is going to do nothing? That's incorrect, opening up the intake AND exhaust absolutely HAS to create a more profound effect on engine acceleration and power output, putting those components on won't leave the engine running as stock. Open up its lungs and let it breathe, it's going to perform better. Doesn't matter what engine you do it to, be it coal, steam, diesel, whatever, it's going to perform better. Believe it or not throttle body spacers do infact work, they create turbulence inside of the intake which causes the air to mix up the fuel spray better. Basically it goes from a small cloud to a very large and potent cloud, either TBI or MPFI. A spacer alone won't do anything more than a modest 1hp increase, it takes an accumulation of components to create a notable effect on engine performance.

FWIW, colder air entering the engine carries more density with it which creates for a more powerful explosion inside of the cylinder. It also helps aid in cooling.
 

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Xpress said:
That's 6-8hp on dyno sheets. If I can find them I will post them, it's adding horsepower. There's no placebo effect to dynomometer results, it's telling you the FACTS as they are. You're just going to arrogantly say that opening up the intake and exhaust is going to do nothing? That's incorrect, opening up the intake AND exhaust absolutely HAS to create a more profound effect on engine acceleration and power output, putting those components on won't leave the engine running as stock. Open up its lungs and let it breathe, it's going to perform better. Doesn't matter what engine you do it to, be it coal, steam, diesel, whatever, it's going to perform better. Believe it or not throttle body spacers do infact work, they create turbulence inside of the intake which causes the air to mix up the fuel spray better. Basically it goes from a small cloud to a very large and potent cloud, either TBI or MPFI. A spacer alone won't do anything more than a modest 1hp increase, it takes an accumulation of components to create a notable effect on engine performance.

FWIW, colder air entering the engine carries more density with it which creates for a more powerful explosion inside of the cylinder. It also helps aid in cooling.
You would have been an easy buyer to get rid of the junk that was on my Jeep. :)

Talk to me when you can tell the power difference, when the power to money ratio is below 25:1.

The only time that 8hp is worth $600 in junk is when you are peaking a high performance engine on a high performance race car.

You also arent getting any better flow, or colder with these "CAI" until you route it under the vehicle, or abover with a induction port or scoop you will still be using under the hood heated air temperatures through a plastic tube. The exact same thing your stock intake does.

Show me these dyno sheets, and then ill show you that the 8hp comes in at some stupid high non commonly used RPM. Especially in a 2.5l MPFI engine that slightly produces more than 100hp.

Your money, your time. I got rid of it, and my rig runs 100% the same.
 

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Sandstorm: it's true that six or eight horses are going to be hard to feel, but easier breathing is always more efficient, and I think intake upgrades would compliment your exhaust. I always put them on with the hope of increased fuel economy. On my '02 Dodge Ram 4.7 gas, I gained a solid 2 mpg with a K&N FIPK and I got about 1.5 out of my '07 Ram Cummins diesel with an S&B CAI. Both have stock exhaust, and mpg was calculated over several tanks. When you are getting 12 mpg, a two point increase is a lot, and the higher the price of gas and the bigger the gain percentage-wise, the quicker they pay for themselves. I can't say the gain will be significant on a 2.5, but if my YJ ever becomes a daily driver, I will probably try one based on previous results. IMO it is a kinda costly 8 hp, but how many power upgrades pay for themselves over time?
 

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Instead of shooting the OP down why don't we just help him out since it is HIS jeep and HIS and leave out our opinions
 
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