jxman25

hey guys i did a search but dident find what i was looking for. my 91 xj is completley stock but hope to change that very soon. anyways ive been thinking about changing it to a cold air intake. So my question is, what should i get that will work the best and give me the most bang for my buck. also for wheeling is there a down side to having a cold air intake? thanks for looking guys. Jesse

xjheep92

There are tons of posts on this topic
Check out totm (topic of the month)
My vote is make a cowl cold air intake using the stock air box. Cheap cold air and it puts the intake up higher to avoid water

jxman25

ok thanks ill look it up there. ive seen pics of the cowl but what makes it a cold air? or how do you mod the stock airbox for it?

Outlaw Star

There is also a sensor and stock airbox mod for as much gain as a cold air intake. All it really costs is the price of a K&N filter. The sensor mod tricks the ECU into thinking there's cooler air coming into the motor.

mr white

So it just makes it run rich?

Outlaw Star

No the O2 and MAP sensors work still to keep the air fuel ratio in check. The sensors are in a bad location from the factory. When the engine gets to running temp the sensor is hot and the engine reads a hot temp as a lean condition. ECU responds by richening the fuel mix, this helps to cool the cylinders and causes you to waste gas. With the mod it gets more of a constant temp reading and fuel usage.

Rockhead

Check out my Thread, on page 3 now. Thread title "J8-inspired hood scoop". The cost is low, no K&N filter to buy.

Jeepzjlover

I've got a cowl air intake but what's this sensor trick.

Outlaw Star

Relocate the AIT (air intake tempature) sensor from the manifold to the airbox. Keeps it off the exhaust manifold heat and keeps it cleaner.

Jeepzjlover

If this is the case why wouldn't the factory have done this? It sounds good and reasonable but hmmm never heard of this one before?

mr white

The factory is retarded. :P

subi_stout

there are plenty of things the factory could have done for every vehicle... it all comes down to cost...

jomps

pics?

2k xj

The cold air all comes down to the density of the air. The hot air under the hood is no good. The cold part of cold air Intake, is all about getting cooler cleaner air. Thats why the factory always pulls air from a fender or front of the engine bay. You can gain more horse power from switching to fully synthetic oil.

Outlaw Star

This works too. Like I said the sensor mod really isn't for more HP but more about fuel usage.