eignub

i guess these guys dont do any research then http://www.fourwheeler.com/how-to/en...ing-true-lies/

Rogue4x4

This is where I said BS
"older XJs probably just feel faster because they have less sound deadening material and some other heavy components"

ehall

I didn't see their research, I saw their conclusions. Not that I disagree with any of it, but its not science.

Efficiency improvements feel like power improvements because less waste results in more of the same power being made available to the powertrain. Its not more power its just more power where you want it and less where you don't.

Ianf406

The spectre/62mm TB pulls enough air to keep my Stroker running a but lean even with 24lb injectors. Cant say what that will do for a stock XJ but it can pull all that is needed.

I will say that there is no way that sucking in cold air hurts your performance. Having the intake higher is always a plus too.I have always felt a gain from having my xjs run as efficiently as possible.

XJlimitedx99

This quote from that article is how I feel on the 62mm tb topic: "We did see a 5hp difference with a 62mm throttle body on a 4.0L with a cold air intake and exhaust modifications and believe the increase would be larger with other airflow enhancements, like a larger camshaft or high-flow cylinder head. It's a complementary component best used in concert with other products."

I also found it interesting that they saw a 1hp gain on the dyno with a tb spacer

extrashaky

I share that approach. I wouldn't bother putting a cold air intake on a stock 4.0L unless I were just interested in getting the intake up higher to avoid water. The stock 4.0L airbox already gives the motor all the air it needs.

However, I'm running a 4.6L stroker with 24lb injectors, Torque Tubes header and high-flow cat and exhaust. That engine needs a bored throttle body and benefits from the CAI. I definitely want to let it breathe. That's why I bought the Spectre.

But the stock airbox doesn't become a restriction until you have an engine that needs more air.

LOL at that. My Toyota-designed Subaru came with a hole in the passenger side footwell that has a pipe running to the intake, so that intake noise is actually piped into the cabin. The reason they did this was to make the car "feel" faster to the driver, since he was hearing more happening when he hit the accelerator.

The car guys who know better immediately plugged the sound tube upon getting the car (there's actually a plug supplied with the car just for that purpose). A lot of people have removed the sound tube altogether. But the market research told Toyota that people in general thought the car was faster when they could hear more of that boxer motor ticking away.

I think there really is a psychological placebo effect of increased sound working on your brain to make you think more is happening. It wouldn't surprise me if an older Jeep would seem faster to the untrained ear because it was louder. When I was a teenager, for a while I drove a slow '59 Chevy Apache with an unmuffled 6-cylinder in it, and a lot of people assumed that just because it was loud, it was fast. I used to get idiots in 5.0L Mustangs pull up beside me at red lights and rev their engines, trying to get me to race. I would laugh, shift the three-speed tree shifter into first and enjoy the teeth-rattling massage as the entire truck shuddered when I engaged the clutch.

Hardkor

I just want to remove my stock airbox to make room for a second battery. CAI makes this possible. Not sure I want to spend the change spectre or Thor is asking tho.

SeriousOffroad

https://www.cherokeeforum.com/f5/col...2/#post1016112

extrashaky

FYI, Advance Auto carries the Spectre on their website for pretty much the same price as everyone else, EXCEPT that Advance always has some kind of discount code that knocks a bunch off the price. I got mine for $117 shipped, and they just had a $50 off $125 promotion that would have made it even cheaper. If that puts it in your ball park, wait until Advance is running another one of those promotions and jump on it.