Alright, i have a 1997 XJ with 150k miles. Friend has a 2001 XJ with 80k miles. My xj had on it originally 31 bfg tires with aluminum wheels and 3 inch lift. went to a jeep jamboree in Louisiana so i put 31.11.50 tsl super swampers on heavy 10 inch STEEL cragers. He has a 4.5 inch lift with 32.10.50 Michelin street tires on aluminum wheels. Everything on both motors was stock except for CAI. My XJ was loaded down way more than his and i still smoked him in a race from a dead-stop and from a roll on the highway. both had same gears 3.55's. Now his XJ has the bigger intake in it (which supposedly puts out more HP) so why did i beat his XJ?

 

Just the intake maniflod is not going to make that big of difference. There are just to many variables. Maybe he had bad gas.... or not who knows. Maybe the other driver had one to many egg mcmuffins that morning.

 

It's not going to make any difference really with the swap.

 

AHH NEGATIVE... dyno proven... 26.9hp... read all about it... stuff like this needs numbers... not opinions...

http://www.mallcrawlin.com/forum/showthread.php?t=6355

 

same trannys? one had more gas then the other... fat wife in the car... no tellin man... could be anything... even old oil vs. new oil...

 

well he has the slip-yoke eliminator. does that make a difference? Both were just topped off with gas and new oil changes (hence going to louisiana) and he had just him=170 pounds, i have myself 140 pounds and my dad 250 pounds, i probably had 4 or 500 more pounds in my jeep. plus running boggers and he had road tires that were about bald.........its just weird that im overloaded and win and he has hardly anything in his jeep way newer motor.

 

So if i swapped i'd produce bout 15 more horsepower. thats a pretty good cheap bolt on i'd say

 

he could have something wrong and dont even know it... lack of fuel and the computers setting the air intake to match... to much fuel and its drowning... i mean theres no tellin... and yeah thats a mod worth doing...

 

No, the 01 has a different tranny. and 31's on 3.55 gears are gonna be a little quicker than 32's on 3.55 gears as well. Though that's not saying much.

 

Because he has the rev limiter and you don't.

 

There's a myth busting article over at jpmagazine saying that when they installed the late model intake on their '98 XJ test mule, the dyno showed a 5hp DECREASE from the base line.

 

i actually read that article. GOOD INFO! now, the swap does hold merit though if more aggressive cam profile is made along with other head mods. it's one of those things yu think will start out as a cheap performance upgrade, but really could cost you a bit more than what you planned.

 

The tires and wheels i had running on my xj weighed twice as much as his set of four 32's so thats saying alot.

 

Well two other guys on here said a 98 xj had a decrease of 5 horsepower when it was put on..........I dont want to lose horsepower.........I dont even know iif i should put this intake on my jeep if im going to lose horsepower. I keep getting flip-flopped answers..............................

 

if you are unsure, don't do it. i highly recommend doing some research to figure out the pros and cons. only then will you really know.