2.5 Performance

[T-rav]

Hey guys. what are some good good mods that I can throw on the 2.5. Running 33" 12.50 and looking for a little more power. Pushing about 60mph on highway but need a little more accleration since im driving on the beach sometimes.

 

[Bounty__Hunter]

Best mod is regearing the axles with lower gears to get the engine operating back in the proper power band.

Otherwise I'd look at replacing the mechanical fan with an electric like the Taurus 3.8L fan, installing a performance cam, high-flow intake and exhaust.

These mods and more have made my '95 2.5 a lot of fun to drive, on road and off.

 

[T-rav]

What gears would you suggest ?

 

[Bounty__Hunter]

4.88, it's as low as you can go in the stock axles. You likely have 4.11 gears now if you have the 5spd.

Also check out 4BangerJP.com - Index for good 2.5L info.

 

[T-rav]

Yeah the gears are 4.11 how hard are these to change. I do all the work to my jeep but never anything with gears.

 

[Bounty__Hunter]

Changing gears is pretty involved, requires setup bearings, a micrometer, dial indicator, etc. Most shops would charge $300+ labor per axle if it gives you any idea.

 

[T-rav]

Yeah that does dude I appreciate it. I think im just going to take it down to the shop this weekend. Maybe they wont get to crazy with the bill.

 

[stngbn95yj]

Hey Bounty Hunter ,
I'm new to jeepz I also have a 95yj have been reading the forums for about a week. Have found alot of the parts you have been talking about except the performance cam , can give more on specifics of the manufacturer ?

 

[Bounty__Hunter]

Mine is a Mopar Performance cam which they no longer manufacture. Look to Clifford Performance, Hesco, or other cam specific companies and see what they have.

 

[Team Twisted Off Road]

Hey Bounty Hunter ,
I'm new to jeepz I also have a 95yj have been reading the forums for about a week. Have found alot of the parts you have been talking about except the performance cam , can give more on specifics of the manufacturer ?

Look here for comp cam info. http://www.jeepz.com/forum/cj-yj-tj-jk/28507-2-5-cam-performance-comp-cam-info.html

 

[stngbn95yj]

Thanks for all the help , this is my final hard project besides my gears and the ring and pinion that need to be replaced. Will advise on how these go, 488 front and rear needed , have 411s now.

 

[jfrabat]

Thanks for all the help , this is my final hard project besides my gears and the ring and pinion that need to be replaced. Will advise on how these go, 488 front and rear needed , have 411s now.

You'll notice HUGE difference with the 488's...

 

[stngbn95yj]

Im also at a delema, want to keep the 2.5 L have several influences that the upgrades wont be enough to raise the horses or the torque. I'm content with the 2.5 L just needs to have an overhaul it is 15 years old. Does any one have any words of encouragement....?
Thanks jfrabat for the info and ur upgrades to look at!

 

[stngbn95yj]

The influences are non existent looked around and did my homework, WOW the conversions are expensive !! That doesn't include the engine or the wiring harness or possible or most likely bellhousing replacement or spline change. Took the air dampering out of the airbox the wife says she notices a difference in horsepower and the idle has leveled itself out, thanks for the tip throttle body and spacer next. 2.5 liter to stay

 

[jfrabat]

Well, if you are willing to drop 3K on the 2.5L, you can always get a turbo kit like this one... Would be cheaper if you do it yourself, but requires you do some tinkering and some trial and error.

 

[stngbn95yj]

Jfrabat ,
Got your idea thanks ! Just noticed the great gas mileage since removing the restrictor in the airbox WOW more horsepower. Need to replace the ring and pinion soon will probably replace the gears to 4:88 s need 5th gear back . With all the upgrades those of you have given there is no reason the 2.5 wont handle the times we drive in.
thanks again Stngbn95yj

 

[jfrabat]

Well, I am half way now on a 600 mile road trip, and I have no complaints about the 4 banger. I've driven most of the 300 or so miles so far on 4th gear, but there were quite a few hills on the way... But then again, I do run 33's on 4.88. I can drive on fifth if I drive at 55mph, but if I go higher, the wind resistance is just too much for the little engine that could. Boy, do I wish I could go to 5.13's without having to swap axles!!!

 

[quicksand97]

Does a eletric fan really work to free up HP, I was thinking of getting one for my 97 4 Banger then I also heard it could rob HP by using up more amp draw. So whats true?

 

[Bounty__Hunter]

It should free up some HP, but it's nothing you can feel, more of a small part of an overall package to improve power and mileage. Not to mention getting rid of the huge fan shroud, you can actually stand on the front axle to service the engine.

If you have a decent fan controller, depending on the weather the 2.5L runs pretty cool and the fan will often be off.

 

[jfrabat]

It should free up some HP, but it's nothing you can feel, more of a small part of an overall package to improve power and mileage.

I could feel it when in 5th gear and going uphill I would downshift later than I would with the mechanical fan; other than that, I could not feel any difference.

Not to mention getting rid of the huge fan shroud, you can actually stand on the front axle to service the engine.

You must weight less than I do; even with the eFan, there's no way I can fit in there! Of course, I am 6´5¨and weight 235 pounds...