2.5L performance?

northshore29 · #1 (**permalink**) 02-26-2006, 06:59 PM

i have a tj with a 2.5L. i am now running a 2" susp. lift with 31x10.5 tires. as far as performance, i have K&N a/f (not intake), power-aid throttlebody spacer, homemade 8mm sparkplug wires, and a summit glasspack instead of stock muffler. any other 2.5L tj owners know of a good way to get a little more kick out of the 2.5L to help with those knarly hills?

Bounty__Hunter · #2 (**permalink**) 02-26-2006, 10:10 PM

www.4bangerjp.com . Consider a 4.0L throttle body and an electric fan. Then the mods get a little more involved.

KrazyJeeper · #3 (**permalink**) 02-26-2006, 10:17 PM

I was told by a mechanic to change the gears. Don't know for sure myself.

Bounty__Hunter · #4 (**permalink**) 02-27-2006, 01:57 AM

I wouldn't necessarily spend the time and money to regear at 31" tires, but definately would at 33". I run stock 4.10 axle gears with 33" tires and, with many performance mods, it does okay. Of course regearing will get you the most noticable performance improvement.

Sparky-Watts · #5 (**permalink**) 02-27-2006, 05:56 AM

What Bounty said. Don't know what year you have, but if it's after '91 (I think), there's an intake restrictor you can pull that I did that gave me a bit more noticeable gain. With the TBS, intake tube pulled, and an electric fan, I found a couple more ponies. Nothing breath taking, but it pulls better up hills and into the wind now.

jakbob · #6 (**permalink**) 02-27-2006, 03:34 PM

i made kind of a larger intake by using the stock components....i cut the stock airboxes intake a little larger and took out the tubing in the airbox...its louder, but i can feel the torque at 2 grand, heres a picture

northshore29 · #7 (**permalink**) 02-27-2006, 07:34 PM

have any of you tried those performance chips that trick your pcm to think the air temp is colder than it really is? i imagine it would just ruin your gas mileage dumping that extra fuel, but w/ a 4.0L throttle body, ram air intake, and maybe a header i'm thinking i could get an extra 15-25hp. if anyone has a wild hair and extra $600-$700 to try it let me know how it goes.

TwistedCopper · #8 (**permalink**) 02-27-2006, 08:33 PM

I can't imagine any single performance mod for a 2.5L costing $600 and being worth it.

That said, I had mine running pretty good on 32's with an opened intake (removed airflow restrictor and installed a drop-in K&N), a performance muffler, splitfire plugs, elec fan conversion, and I think I'm forgetting something else but these are it for the most part.

None of the above-mentioned mods will knock your socks off, but done together they can get an old 2.5L running pretty good even with 31-33" tires. They won't win any races but I consistantly got 20 mpg on the highway in my old YJ.

mud4feet · #9 (**permalink**) 02-27-2006, 09:14 PM

And the gnarly hills aren't the problem...........it's those danged paved ones!

currupt4130 · #10 (**permalink**) 02-28-2006, 08:06 AM

I could pull 65 on the highway on 35's no problem with a 4 spd, thats pretty much the same as regearing. now on 38's the 4 banger is lacking a little bit even with 5.13's. I can get her to 50, but to tell you the truth, im scared to go over that with it now

gentrydavid · #11 (**permalink**) 02-28-2006, 08:15 PM

In short there is no good cost effective solution to a 2.5. Trade in or sell on a 4.0 and you will be much happier i know i am.

currupt4130 · #12 (**permalink**) 02-28-2006, 08:19 PM

the 4 banger is the beast of burden for jeep. i love it and wouldnt trade it for anything else

mud4feet · #13 (**permalink**) 02-28-2006, 10:09 PM

Quote:

Originally Posted by currupt4130

the 4 banger is the beast of burden for jeep. i love it and wouldnt trade it for anything else

X2, Corrupt. I still can't believe it's being discontinued in the '07's.

northshore29 · #14 (**permalink**) 03-01-2006, 08:16 PM

i got to much in my jeep to sell and come out ahead, i tried to sell for a few months, but no luck so now i'm just gonna dump more money into it so i don't get bored with it. later on down the road i might swap the motor and everything else that goes with it.

northshore29 · #15 (**permalink**) 03-01-2006, 08:21 PM

one thing i do like about my 2.5L is that it's so easy to work on. everything is out on the open and easy to get to. although nothing has broken yet....but when it does i won't be as ticked.

Sparky-Watts · #16 (**permalink**) 03-01-2006, 08:54 PM

Wait till you put in the electric fan....that opens up enough room on the front of the engine compartment to actually stand between the engine and the radiator!!