Topic: (Need Advice) Added Horsepower for 2.5L

[carrawaych]

I have purchased a 1998 SE wrangler. Come to find out the dealer ripped me off and priced and sold it as a 6cylinder, which sadly I found out after the deal it was a 4 cylinder. Very upset about this. The exterior is in excellent condition. but the output in power is just not enough for me. I cant afford a engine swap. All Im really trying to attain right now is an up hill highway climb going at-least 70 in fourth gear, or even better 5th gear. Experience, knowledge and a list of products to purchase, an minimal cost would be highly appreciated. I believe the 6 cylinder has about 60 more horsepower then the 4, reaching more then half of this would be exciting. Thanks for your time?

[sharpxmen]

I have purchased a 1998 SE wrangler. Come to find out the dealer ripped me off and priced and sold it as a 6cylinder, which sadly I found out after the deal it was a 4 cylinder. Very upset about this. The exterior is in excellent condition. but the output in power is just not enough for me. I cant afford a engine swap. All Im really trying to attain right now is an up hill highway climb going at-least 70 in fourth gear, or even better 5th gear. Experience, knowledge and a list of products to purchase, an minimal cost would be highly appreciated. I believe the 6 cylinder has about 60 more horsepower then the 4, reaching more then half of this would be exciting. Thanks for your time?

take it back if it sold it to you as a 6 cyl, and ask for one that matches the agreement. If he refuses contact BBB and if he still refuses take him to court for the difference.

[chrisfranklin]

Sorry to hear that -- as much as I appreciate the 4banger, I hate to see somebody not get the Jeep that s(he) anticipated. 

Do you have anything in writing (and I mean anything) showing that the dealer represented that the jeep he sold you was a 6 cylinder, 4.0L '98 SE -- say, window sticker, paper work from your purchase transaction, ads that the dealer placed in the local paper advertising your Jeep? 

That's a good start on setting things right if you do.   




   

[firebrick43]

I don't mean to be mean, but someone has to tell the the truth.

If you didn't know the difference between a 4 and 6 cylinder engine when you looked at the car, you don't have the mechanical skills at this time to be making performance modifications.  You are going to screw something up royally. 

[sharpxmen]

I don't mean to be mean, but someone has to tell the the truth.

If you didn't know the difference between a 4 and 6 cylinder engine when you looked at the car, you don't have the mechanical skills at this time to be making performance modifications.  You are going to screw something up royally. 

if you cruise this site long enough you'll find people making most of their mods for the first time and being successful, you don't have to be a mechanic to replace an air filter or throttle body, would take longer but you'll eventually come through.

and there isn't much difference between the 2 engines other than 2 extra cylinders...

[firebrick43]

I generally agree with you sharpaxeman, people have to start some where with performance mods.  But still most have change oil, spark plugs, wires, ect, under stand how an engine works.  To me its just mind boggling that some one wouldn't pop the hood and look at the motor when buying.  If they did and still didn't know that it was a 4 cylinder it tells me that they don't know even the basics such as torque, application of gaskets/sealer/antiseize, ect.  If you don't know that stuff, changing the throttle body can be difficult and the potential for damage is great.  When taking my 4.0L throttle body apart I had problems getting the map sensor screws to come out and I am a mechanic/machinist buy profession. 

[sharpxmen]

we all had to start somewhere - i wouldn't think he'll start on with replacing the camshaft, but if you're handy all the little things are in reach. Just don't think you should discourage him right off the bat, like i said with little help, starting small and fighting thru the challenges (like the bolts you mentioned) would give you more gratification (mostly that's why we all work on our Jeeps). I do understand what you mean though, i just think that if there is a will there is a way but weigh your projects wisely (i have a problem with that myself :)

[blacknblue]

Any way you look at it,  more horsepower is going to cost you.  This place is a great start to find out what you can afford and have the skills to install.  Most people start with a 4.0 throttle body and a spacer,  Banks makes a good header and exhaust,  a firepower ignition (cap,rotor,wires,plugs), Jet makes chips that easy to install but really only work with other modifications done first. There is only so much you can do to a 2.5 short of rebuilding it or replacing it.  Most of the modifications only make the 2.5 acceptable to drive.  Learn to enjoy driving slower.

[chrisfranklin]

  Most of the modifications only make the 2.5 acceptable to drive. 

Well said blacknblue    Some engine mods to the 4banger will take it from kinda awful to acceptable.     

[aka-justin]

It's a slippery slope to power up the 4 banger.  If you accept defeat now and want to enjoy slower speeds, any gain with mods will feel that much better   If you speed is all you need, 1. be ready for some poor mpg (as a brick is not aero dynamic) , and 2. I would persue (as mentioned) getting what is right from the dealer and get your 6 cyclinder.

The performance modifications for the 4.0 engine (cams, headers, reprogrammers, etc.) are far more dramatic and expensive, whereas they're far and few between for our 2.5's.  For me, low and slow is expected as is the application of most 4x4s.  It's to get over ruff terrian, not as much to fly down the freeway.  The 6 cyclinder will propell you, but at a higher MPG then any other vehicle.  I hate to be blunt, but I feel I need to be straight.

I've done the throttle body swap off a 4.0 6cyc, and it did little to improve my top end (if not weakend it), but much to my low end power, so I don't stall on hills as often.  The fact is now there's soo much air, the engine starves for fuel.  The fuel injectors and fuel pressure regulator would need to be replaced to take advantage of the extra air for once I crank the pedal to the floor.  To that extent, the computer will need to be re-adjust as any major changes will cause the computers emission controlls to counteract; unless the computer can be altered by either program or modifing sensor inputs.  Again, It's a slippery slope to power up the 4 banger.

Hope you enjoy Jeeping and everything works out as you need.

[aka-justin]

If anyone is interested (in falling asleep), here's some good reads on the computer's role in adjusting air fuel ratios for emissions...

http://www.autoshop101.com/forms/h58.pdf

http://www.waset.org/journals/waset/v48/v48-47.pdf

http://vehicle.me.berkeley.edu/~jsouder/souderhedrickAFR.pdf